RANDOM ACCESS SEQUENCE GENERATION METHOD, DEVICE, AND SYSTEM

Abstract

Embodiments of the present application provide a random access sequence generation method, and an apparatus. The method includes: generating, by a base station, notification signaling, where the notification signaling includes indication information, the indication information is used to instruct user equipment UE to select a shift sequence number from a range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the shift sequence number is an integer, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, n.sub.group.sup.RA is a quantity of groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in the last length that is insufficient for a group, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in first remaining sequence shifts, and .sub.shift.sup.RA is a quantity of UE candidate sequence shifts in second remaining sequence shifts; and sending, by the base station, the notification signaling to the UE, so that the UE generates a random access sequence according to the indication information.

Claims

1. A method for generating a random access sequence in a communication system, comprising: obtaining, by a communication apparatus, a cyclic shift value C.sub.v according to a shift sequence number v, wherein:
C.sub.v=d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1), wherein v is an integer, N.sub.CS is a quantity of cyclic shifts for a user equipment, wherein n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29), respectively, wherein $\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{4.Math.d_c-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(4\right)\\ d_{\mathrm{start}}=4.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}},& \left(5\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(12\right)\\ d_{\mathrm{start}}=N_{\mathrm{ZC}}-3.Math.d_u+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}},& \left(13\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(20\right)\\ d_{\mathrm{start}}=3.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}},& \left(21\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-2.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(28\right)\\ d_{\mathrm{start}}=2.Math.\left(N_{\mathrm{ZC}}-2.Math.d_u\right)+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}},& \left(29\right)\end{array}$ and wherein N.sub.ZC is a length of the random access sequence, a root of the random access sequence is u, $d_u=\{\begin{array}{cc}p& 0p<N_{\mathrm{ZC}}/2\\ N_{\mathrm{ZC}}-p& \mathrm{another}.Math..Math.\mathrm{value}\end{array},$ and p is a minimum non-negative integer that satisfies (pu)mod N.sub.ZC=1; and generating, by the communication apparatus, the random access sequence according to the cyclic shift value C.sub.v.

2. The method according to claim 1, wherein for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), or for $\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), or for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math.N_{\mathrm{ZC}}}{5},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), or for $\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29).

3. The method according to claim 1, wherein the generating the random access sequence according to the cyclic shift value C.sub.v, comprising: generating, by the communication apparatus, the random access sequence x.sub.u,C.sub.v(n) according to the cyclic shift value C.sub.v, meeting formula (36):
x.sub.u,C.sub.v(n)=x.sub.u((n+C.sub.v)mod N.sub.ZC)(36), wherein the root of the random access sequence u satisfies $x_u\left(n\right)=e^{-j.Math.\frac{.Math..Math.\mathrm{un}\left(n+1\right)}{N_{\mathrm{ZC}}}},$ 0nN.sub.ZC1.

4. The method according to claim 1, wherein a range of the shift sequence number v is from 0 to to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), wherein for n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), n.sub.group, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (6) to (8) and (10), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (14) to (16) and (18), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (22) to (24) and (26), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (30) to (32) and (34), wherein $\begin{array}{cc}.Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(6\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(7\right)\\ {\stackrel{\_}{\stackrel{\_}{n}}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},4.Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.,& \left(8\right)\\ {\stackrel{\_}{\stackrel{\_}{\stackrel{\_}{n}}}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.(\left(1-\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right)\right).Math.\left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d\right)+\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right).Math.(4.Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}.Math.-{\stackrel{\_}{\stackrel{\_}{n}}}_{\mathrm{shift}}^{\mathrm{RA}},& \left(10\right)\\ .Math.n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(14\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(15\right)\\ {\stackrel{\_}{\stackrel{\_}{n}}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},N_{\mathrm{ZC}}-3.Math.d_u-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.,& \left(16\right)\\ .Math.{\stackrel{\_}{\stackrel{\_}{\stackrel{\_}{n}}}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(18\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(22\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-2.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(23\right)\\ .Math.{\stackrel{\_}{\stackrel{\_}{n}}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(24\right)\\ .Math.{\stackrel{\_}{\stackrel{\_}{\stackrel{\_}{n}}}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(26\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-d_u}{d_{\mathrm{start}}}.Math.,& \left(30\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(31\right)\\ .Math.{\stackrel{\_}{\stackrel{\_}{n}}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(32\right)\\ .Math.{\stackrel{\_}{\stackrel{\_}{\stackrel{\_}{n}}}}_{\mathrm{shift}}^{\mathrm{RA}}=0.& \left(34\right)\end{array}$

5. The method according to claim 4, wherein v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1).

6. The method according to claim 4, before the obtaining, by the communication apparatus, the cyclic shift value C.sub.v, further comprises: transmitting, by the communication apparatus, indication information which indicates the range of the shift sequence number v.

7. The method according to claim 4, before the obtaining, by the communication apparatus, the cyclic shift value C.sub.v, further comprises: receiving, by the communication apparatus, indication information which indicates the range of the shift sequence number v.

8. The method according to claim 1, after the generating, by the communication apparatus, the random access sequence, further comprising: transmitting, by the communication apparatus, the random access sequence.

9. The method according to claim 1, after the generating, by the communication apparatus, the random access sequence, further comprising: detecting, by the communication apparatus, another random access sequence according to the generated random access sequence.

10. The method according to claim 1, wherein d.sub.u is a cyclic shift corresponding to the random access sequence when a Doppler frequency shift is a physical random access channel (PRACH) subcarrier spacing.

11. An apparatus, comprising: a memory; and a processor coupled to the memory, and configured to execute the instructions included in the memory to: obtain a cyclic shift value C.sub.v according to a shift sequence number v, wherein
C.sub.v=d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1), wherein v is an integer, N.sub.CS is a quantity of cyclic shifts for a user equipment, wherein n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29), respectively, wherein $\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(4\right)\\ d_{\mathrm{start}}=4.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(5\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(12\right)\\ d_{\mathrm{start}}=N_{\mathrm{ZC}}-3.Math.d_u+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(13\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(20\right)\\ d_{\mathrm{start}}=3.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(21\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(28\right)\\ d_{\mathrm{start}}=2.Math.\left(N_{\mathrm{ZC}}-2.Math.d_n\right)+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(29\right)\end{array}$ and wherein N.sub.ZC is a length of a random access sequence, a root of the random access sequence is u, $d_u=\{\begin{array}{cc}p& 0p<N_{\mathrm{ZC}}/2\\ N_{\mathrm{ZC}}-p& \mathrm{another}.Math..Math.\mathrm{value}\end{array},$ and p is a minimum non-negative integer that satisfies (pu)mod N.sub.ZC=1; and generate the random access sequence according to the cyclic shift value C.sub.v.

12. The apparatus according to claim 11, wherein for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), or for $\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), or for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math.N_{\mathrm{ZC}}}{5},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), or for $\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29).

13. The apparatus according to claim 11, wherein the processor is further configured to execute the instructions to cause the apparatus to: generate the random access sequence x.sub.u,C.sub.v(n) according to the cyclic shift value C.sub.v meeting formula (36):
x.sub.u,C.sub.v(n)=x.sub.u((n+C.sub.v)mod N.sub.ZC)(36), wherein the root of the random access sequence u satisfies $x_u\left(n\right)=e^{-j.Math..Math.\frac{.Math..Math.\mathrm{un}.Math.\left(n+1\right)}{N_{\mathrm{ZC}}}},$
0nN.sub.ZC1.

14. The apparatus according to claim 11, wherein a range of the shift sequence number v is from 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), wherein for n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), n.sub.group, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (6) to (8) and (10), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (14) to (16) and (18), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (22) to (24) and (26), or for n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29), n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, and .sub.shift.sup.RA satisfy formulas (30) to (32) and (34), wherein $\begin{array}{cc}.Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(6\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(7\right)\\ .Math.{\stackrel{=}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},4.Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.,& \left(8\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\left(\left(1-\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right)\right).Math.\left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}\right)+\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right).Math.\left(4.Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)\right)/N_{\mathrm{CS}}.Math.-{\stackrel{=}{n}}_{\mathrm{shift}}^{\mathrm{RA}},& \left(10\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(14\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(15\right)\\ .Math.{\stackrel{=}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},N_{\mathrm{ZC}}-3.Math.d_u-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.,& \left(16\right)\\ .Math.{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(18\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.,& \left(22\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-2.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(23\right)\\ .Math.{\stackrel{=}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(24\right)\\ .Math.{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(26\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-d_u}{d_{\mathrm{start}}}.Math.,& \left(30\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right),& \left(31\right)\\ .Math.{\stackrel{=}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0,& \left(32\right)\\ .Math.{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0.& \left(34\right)\end{array}$

15. The apparatus according to claim 14, wherein v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1).

16. The apparatus according to claim 11, wherein d.sub.u is a cyclic shift corresponding to the random access sequence when a Doppler frequency shift is a physical random access channel (PRACH) subcarrier spacing.

17. A non-transitory computer-readable medium storing computer instructions which, when executed by one or more processors, cause the one or more processors to perform the steps of: obtaining a cyclic shift value C.sub.v according to a shift sequence number v, wherein
C.sub.v=d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1), wherein v is an integer, N.sub.CS is a quantity of cyclic shifts for a user equipment, wherein n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), respectively, or n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29), respectively, wherein $\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(4\right)\\ d_{\mathrm{start}}=4.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(5\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(12\right)\\ d_{\mathrm{start}}=N_{\mathrm{ZC}}-3.Math.d_u+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(13\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,& \left(20\right)\\ d_{\mathrm{start}}=3.Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(21\right)\\ n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,& \left(28\right)\\ d_{\mathrm{start}}=2.Math.\left(N_{\mathrm{ZC}}-2.Math.d_n\right)+n_{\mathrm{shift}}^{\mathrm{RA}.Math.}.Math.N_{\mathrm{CS}},& \left(29\right)\end{array}$ and wherein N.sub.ZC is a length of a random access sequence, a root of the random access sequence is u, $d_u=\{\begin{array}{cc}p& 0p<N_{\mathrm{ZC}}/2\\ N_{\mathrm{ZC}}-p& \mathrm{another}.Math..Math.\mathrm{value}\end{array},$ and p is a minimum non-negative integer that satisfies (pu)mod N.sub.ZC=1; and generating the random access sequence according to the cyclic shift value C.sub.v.

18. The non-transitory computer-readable medium according to claim 17, wherein for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (4) and (5), or for $\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (12) and (13), or for $\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math.N_{\mathrm{ZC}}}{5},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (20) and (21), or for $\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$ n.sub.shift.sup.RA and d.sub.start satisfy formulas (28) and (29).

19. The non-transitory computer-readable medium according to claim 17, wherein the generating the random access sequence according to the cyclic shift value C.sub.v, comprises: generating the random access sequence x.sub.u,C.sub.v(n) according to the cyclic shift value C.sub.v meeting formula (36):
x.sub.u,C.sub.v(n)=x.sub.u((n+C.sub.v)mod N.sub.ZC)(36), wherein the root of the random access sequence u satisfies $x_u\left(n\right)=e^{-j.Math..Math.\frac{.Math..Math.\mathrm{un}.Math.\left(n+1\right)}{N_{\mathrm{ZC}}}},$ 0nN.sub.ZC1.

20. The non-transitory computer-readable medium according to claim 17, wherein a range of the shift sequence number v is from 0 to v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1).

Description

BRIEF DESCRIPTION OF DRAWINGS

[0167] To describe the technical solutions in the embodiments of the present application more clearly, the following briefly describes the accompanying drawings required for describing the embodiments. Apparently, the accompanying drawings in the following description show some embodiments of the present application, and persons of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

[0168] FIG. 1 is a flowchart of Embodiment 1 of a random access sequence generation method according to the present application;

[0169] FIG. 2 is a flowchart of Embodiment 2 of a random access sequence generation method according to the present application;

[0170] FIG. 3 is a schematic diagram of scenario 1 according to an embodiment of the present application;

[0171] FIG. 4 is a schematic diagram of scenario 2 according to an embodiment of the present application;

[0172] FIG. 5 is a schematic diagram of scenario 3 according to an embodiment of the present application;

[0173] FIG. 6 is a schematic diagram of scenario 4 according to an embodiment of the present application;

[0174] FIG. 7 is a schematic diagram of scenario 5 according to an embodiment of the present application;

[0175] FIG. 8 is a schematic diagram of scenario 6 according to an embodiment of the present application;

[0176] FIG. 9 is a schematic diagram of scenario 7 according to an embodiment of the present application;

[0177] FIG. 10 is a flowchart of Embodiment 3 of a random access sequence generation method according to the present application;

[0178] FIG. 11 is a flowchart of Embodiment 5 of a random access sequence generation method according to the present application;

[0179] FIG. 12 is a flowchart of Embodiment 6 of a random access sequence generation method according to the present application;

[0180] FIG. 13 is a schematic structural diagram of Embodiment 1 of a base station according to the present application;

[0181] FIG. 14 is a schematic structural diagram of Embodiment 2 of a base station according to the present application;

[0182] FIG. 15 is a schematic structural diagram of Embodiment 1 of user equipment according to the present application;

[0183] FIG. 16 is a schematic structural diagram of Embodiment 3 of a base station according to the present application;

[0184] FIG. 17 is a schematic structural diagram of Embodiment 3 of user equipment according to the present application;

[0185] FIG. 18 is a schematic structural diagram of Embodiment 4 of a base station according to the present application;

[0186] FIG. 19 is a schematic structural diagram of Embodiment 4 of user equipment according to the present application; and

[0187] FIG. 20 is a schematic structural diagram of Embodiment 5 of a base station according to the present application.

DESCRIPTION OF EMBODIMENTS

[0188] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the following clearly describes the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some but not all of the embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0189] FIG. 1 is a flowchart of Embodiment 1 of a random access sequence generation method according to the present application. As shown in FIG. 1, the method in this embodiment may include:

[0190] Step 101: A base station generates notification signaling, where the notification signaling includes indication information, the indication information is used to instruct user equipment UE to select a shift sequence number from a range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the shift sequence number is an integer, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, n.sub.group.sup.RA is a quantity of groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in the last length that is insufficient for a group, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in first remaining sequence shifts, and .sub.shift.sup.RA is a quantity of UE candidate sequence shifts in second remaining sequence shifts.

[0191] It should be noted that, a group in the present application is a sequence shift group; n.sub.group.sup.RA indicates a quantity of groups obtained after sequence shifts are grouped; n.sub.shift.sup.RA indicates a quantity of UEs that can be distinguished in a sequence shift group aftger sequence shifts are grouped; n.sub.shift.sup.RA indicates a quantity of UEs that are further distinguished in a sequence shift in a remaining length that is insufficient for a group after sequence shifts are grouped; n.sub.shift.sup.RA and .sub.shift.sup.RA indicate quantities of UEs that can be distinguished in remaining discrete sequence shifts of all sequence shifts other than sequence shifts that are definitely occupied by n.sub.shift.sup.RA, n.sub.group.sup.RA, and n.sub.shift.sup.RA.

[0192] Step 102: The base station sends the notification signaling to the UE, so that the UE generates a random access sequence according to the indication information.

[0193] In the conventional art, the UE selects a shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1). In the present application, the base station instructs, by using the notification signaling, the UE to select a shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1).

[0194] In the conventional art, shift sequences are grouped to determine three parameters: a quantity (n.sub.group.sup.RA) of groups, a quantity (n.sub.shift.sup.RA) of UE candidate sequence shifts in a group, and a quantity (n.sub.shift.sup.RA) of UE candidate sequence shifts in the last length that is insufficient for a group; and a shift sequence number is selected from an interval that is determined according to the three parameters. As can be learned, in the conventional art, during determining of a range from which a shift sequence number is selected, a quantity of UEs that can be distinguished is considered from only a perspective of a group, and other remaining discrete shift sequences obtained after grouping are not considered. In the present application, after a quantity of UEs that can be distinguished is considered from a perspective of a group, quantities of UEs that can be further distinguished in other remaining discrete shift sequences obtained after grouping, that is, a quantity (n.sub.shift.sup.RA) of UE candidate sequence shifts in first remaining sequence shifts and a quantity (.sub.shift.sup.RA) of UE candidate sequence shifts in second remaining sequence shifts, are further considered; and the UE is instructed, by using the notification signaling, to select a shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), thereby expanding a range from which a shift sequence number is selected.

[0195] FIG. 2 is a flowchart of Embodiment 2 of a random access sequence generation method according to the present application. As shown in FIG. 2, optionally, after step 102, the method may further include:

[0196] Step 201: The base station selects a shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1).

[0197] Optionally, because the base station cannot learn a shift sequence number that is used by the UE when the UE sends the random access sequence, when the base station detects the random access sequence sent by the UE, the base station sequentially chooses to traverse each shift sequence number in the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shiftt.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1). Alternatively, the base station sequentially chooses to traverse each shift sequence number in a range of 0 to X, X is an integer less than (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1).

[0198] Step 202: The station obtains a cyclic shift value according to the shift sequence number.

[0199] Optionally, the base station obtains the cyclic shift value C.sub.v of the UE according to the shift sequence number v by using the following formula (1), formula (2), or formula (3):

C.sub.v=d.sub.offset+d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1);

C.sub.v=d.sub.offset+d.sub.start+(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA)N.sub.CS(2);

C.sub.v=d.sub.offset+.sub.start+(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA)N.sub.CS(3),

where

[0200] d.sub.offset is a shift offset, d.sub.start is a cyclic shift distance between neighboring groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, N.sub.CS is a quantity of cyclic shifts that are occupied by a user, d.sub.start is a cyclic shift value of a first UE candidate sequence shift in the first remaining sequence shifts, and .sub.start is a cyclic shift value of a first UE candidate sequence shift in the second remaining sequence shifts.

[0201] It should be noted that, d.sub.offset is an integer (which is usually a constant integer), and d.sub.offset used on a base station side and d.sub.offset used on a UE side need to be the same. Optionally, that d.sub.offset used on the base station side and d.sub.offset used on the UE side have a same value may be implemented by means of agreement in advance. For example, d.sub.offset=0.

[0202] It should be noted that, in the present application, Y indicates rounded-down of Y. That is, if Y is equal to 2.5, Y is equal to 2. For example, v/n.sub.shift.sup.RA indicates rounded-down of v/n.sub.shift.sup.RA.

[0203] It should be noted that, in the present application, mod indicates a modulo operation. For example, 4 mod 2=0, and 5 mod 2=1.

[0204] Optionally, in the case of v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift value C.sub.v by using formula (1);

[0205] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift value C.sub.v by using formula (2); or

[0206] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the base station obtains the cylic shift value C.sub.v by using formulas (3).

[0207] Step 203: The base station generates a detection sequence according to the cyclic shift value, and detects, by using the detection sequence, the random access sequence sent by the UE, where the random access sequence is generated by the UE according to the indication information.

[0208] A ZC sequence x.sub.u(n) whose root is u may be defined as:

[00089]$x_u\left(n\right)=e^{-j.Math.\frac{.Math..Math.\mathrm{un}\left(n+1\right)}{N_{\mathrm{ZC}}}},$
0nN.sub.ZC1,

where N.sub.ZC is a length of the ZC sequence, and u is the root of the ZC sequence.

[0209] Specifically, the base station performs cyclic shift on the ZC sequence x.sub.u(n) whose root is u. If the cyclic shift value is K, a ZC sequence generated according to the cyclic shift value is x.sub.u((n+K)mod N.sub.ZC), where N.sub.ZC is a length of the ZC sequence.

[0210] Optionally, the base station performs, by using the detection sequence generated according to the cyclic shift value, related detection on the random access sequence sent by the UE. The base station may perform related detection in a time domain, or may perform detection in a frequency domain according to a frequency domain detection manner corresponding to a time domainrelated detection manner.

[0211] Optionally, in step 202, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11):

[00090]$\begin{array}{cc}.Math.n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{4.Math..Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.;& \left(4\right)\\ .Math.d_{\mathrm{start}}=4.Math..Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}};& \left(5\right)\\ .Math.n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.;& \left(6\right)\\ .Math.{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-3.Math..Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right);& \left(7\right)\\ .Math.{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},4.Math..Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.;& \left(8\right)\\ .Math.{\stackrel{}{d}}_{\mathrm{start}}=N_{\mathrm{ZC}}-3.Math..Math.d_u+n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}+{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.{\stackrel{\_}{N}}_{\mathrm{CS}};& \left(9\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\left(\left(1-\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right)\right).Math.\left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}\right)+\min \left(1,{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}\right).Math.\left(4.Math..Math.d_u-N_{\mathrm{ZC}}-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)\right)/N_{\mathrm{CS}}.Math.-{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}};& \left(10\right)\\ .Math.{\stackrel{}{d}}_{\mathrm{start}}=N_{\mathrm{ZC}}-2.Math..Math.d_u+n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}+{\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}.& \left(11\right)\end{array}$

[0212] Alternatively, in step 202, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19):

[00091]$\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math..Math.d_u}{N_{\mathrm{CS}}}.Math.;& \left(12\right)\\ d_{\mathrm{start}}=N_{\mathrm{ZC}}-3.Math..Math.d_u+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}};& \left(13\right)\\ n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.;& \left(14\right)\\ {\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{4.Math..Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right);& \left(15\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\min \left(d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}},N_{\mathrm{ZC}}-3.Math..Math.d_u-{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}}\right)/N_{\mathrm{CS}}.Math.;& \left(16\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=d_u+n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}+{\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}};& \left(17\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0;& \left(18\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=0.& \left(19\right)\end{array}$

[0213] Alternatively, in step 202, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27):

[00092]$\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math..Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.;& \left(20\right)\\ d_{\mathrm{start}}=3.Math..Math.d_u-N_{\mathrm{ZC}}+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}};& \left(21\right)\\ n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.;& \left(22\right)\\ {\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-2.Math..Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right);& \left(23\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0;& \left(24\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=0;& \left(25\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0;& \left(26\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=0.& \left(27\right)\end{array}$

[0214] Alteratively, in step 202, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35):

[00093]$\begin{array}{cc}{n}_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{\mathrm{NC}-2.Math..Math.d_u}{N_{\mathrm{CS}}}.Math.;& \left(28\right)\\ d_{\mathrm{start}}=2.Math.\left(N_{\mathrm{ZC}}-2.Math..Math.d_u\right)+n_{\mathrm{shift}}^{\mathrm{RA}}.Math.N_{\mathrm{CS}};& \left(29\right)\\ n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-d_u}{d_{\mathrm{start}}}.Math.;& \left(30\right)\\ {\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{3.Math..Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right);& \left(31\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0;& \left(32\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=0;& \left(33\right)\\ {\stackrel{}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=0;& \left(34\right)\\ {\stackrel{}{d}}_{\mathrm{start}}=0,& \left(35\right)\end{array}$

[0215] d.sub.u is a cyclic shift corresponding to the random access sequence when a Doppler frequency shift is one time a PRACH subcarrier spacing.

[0216] Optionally, in the case of

[00094]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11), in the case of

[00095]$\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19).

[0217] Alternatively, in the case of

[00096]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u\frac{2}{7}.Math.N_{\mathrm{ZC}},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11), in the case of

[00097]$\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19).

[0218] Optionally, in the case of

[00098]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math..Math.N_{\mathrm{ZC}}}{5},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27), in the case of

[00099]$\frac{2.Math..Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0219] Alternatively, in the case of

[00100]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u\frac{2.Math..Math.N_{\mathrm{ZC}}}{5},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27), in the case of

[00101]$\frac{2.Math..Math.N_{\mathrm{ZC}}}{5}<d_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0220] It should be noted that, in the present application, max indicates obtaining a maximum value. For example, max (0,1)=1, and max (4,5)=5. min indicates obtaining a minimum value. For example, min (0,1)=0, and min (4,5)=4.

[0221] It should be noted that, any n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start that satisfy formulas (4) to (11), formulas (12) to (19), formulas (20) to (27), or formulas (28) to (35) fall within the protection scope of the present application.

[0222] In this embodiment, the base station selects the shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1); the base station obtains the cyclic shift value according to the shift sequence number; and the base station generates the detection sequence according to the cyclic shift value, and detects, by using the detection sequence, the random access sequence sent by the UE, where the random access sequence is generated by the UE according to the indication information. This resolves a problem that random access sequences of multiple UEs interfere with each other when a Doppler frequency shift is greater than one time a PRACH subcarrier spacing and is less than two times the PRACH subcarrier spacing, avoids interference between random access sequences of multiple UEs, and enables the base station to decode the random access sequence more accurately.

[0223] The following describes a reason why the problem that random access sequences of multiple UEs interfere with each other when a Doppler frequency shift is greater than one time a PRACH subcarrier spacing and is less than two times the PRACH subcarrier spacing in this embodiment can be avoided in the case of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11), formulas (12) to (19), formulas (20) to (27), or formulas (28) to (35).

[0224] Assuming that a signal sent by the UE is r(t)e.sup.j2ft, r(t) is a baseband signal, and e.sup.j2ft is a carrier, a signal obtained after a Doppler frequency shift mf is r(t)e.sup.j2(f+mf)t, where m is a positive integer, and f is one time a PRACH subcarrier spacing.

[0225] According to a property of inverse fast Fourier transform (IFFT), a reciprocal of a frequency domain spacing is equal to a time domain period, and this is equivalent to

[00102]$.Math..Math.f=\frac{1}{N.Math..Math..Math..Math.t},$

where f is a subcarrier spacing, t is a time domain sampling interval, and N is a value of discrete Fourier transform (DFT) or inverse discrete Fourier transform (IDFT).

[0226] t=nt is set, and in this case, r(t)e.sup.j2(f+mf)t=(r(t)e.sup.j2(mn)/N)e.sup.j2ft. (r(t)e.sup.j2(mn)/N) is an equivalent baseband signal.

[0227] Property 1:

[0228] The UE sends the random access sequence to the base station. If there is a Doppler frequency shift mf between receive ends of the UE and the base station, a random access sequence received on the receive end of the base station is a shift sequence of the random access sequence sent by the UE, and there is a fixed phase shift between the two sequences.

[0229] Proof: For example, the Doppler frequency shift is mf. A baseband sampling signal of a time domain t=nt is marked as r(n). For the equivalent baseband signal (r(t)e.sup.j2(mn)/N), N=N.sub.ZC is set. In this case, a baseband sampling signal of the equivalent baseband signal of a ZC sequence is

[00103]$r\left(n\right)=W^{\frac{\mathrm{un}\left(n+1\right)}{2}}.Math.W^{\mathrm{mn}},$

where

[00104]$r\left(n\right)=W^{\frac{\mathrm{un}\left(n+1\right)}{2}}.Math.W^{\mathrm{mn}};$

and

[00105]$\begin{array}{cc}\begin{array}{c}r\left(n\right)=.Math.W^{\frac{\mathrm{un}\left(n+1\right)}{2}}.Math.W^{\mathrm{mn}}\\ =.Math.W^{\frac{u\left[n\left(n+1\right)+2.Math..Math.m\left(1/u\right).Math.n\right]}{2}}\\ =.Math.W^{\frac{u\left[n^2+n+2.Math..Math.m\left(1/u\right).Math.n\right]}{2}}\\ =.Math.W^{\frac{u\left[n\left(n+m\left(1/u\right)+1\right)+m\left(1/u\right).Math.\left(n+m\left(1/u\right)+1\right)-m\left(1/u\right).Math.\left(m\left(1/u\right)+1\right)\right]}{2}}\\ =.Math.W^{\frac{u\left[\left(n+m\left(1/u\right)\right).Math.\left(n+m\left(1/u\right)+1\right)-m\left(1/u\right).Math.\left(m\left(1/u\right)+1\right)\right]}{2}}\\ =.Math.W^{\frac{u\left(n+m\left(1/u\right)\right).Math.\left(n+m\left(1/u\right)+1\right)}{2}}.Math.W^{\frac{-\mathrm{um}\left(1/u\right).Math.(m\left(1/u\right)+1}{2}}\\ =.Math.x_u\left(n+m\left(1/u\right)\right).Math.W^{\frac{-\mathrm{um}\left(1/u\right).Math.\left(m\left(1/u\right)+1\right)}{2}},\end{array}& \left(37\right)\end{array}$

where

[0230] x.sub.u(n) indicates a ZC sequence whose root is u, that is,

[00106]$x_u\left(n\right)=e^{-j.Math.\frac{.Math..Math.\mathrm{un}\left(n+1\right)}{N_{\mathrm{ZC}}}};$

and x.sub.u(n+m(1/u)) indicates a shift sequence of the ZC sequence whose root is u, that is, right cyclic shift is performed on the ZC sequence whose root is u by m(1/u) bits.

[0231] In Formulas (37),

[00107]$\frac{1}{u}$

is defined as a minimum non-negative integer that satisfies ((1/u)u)mod N.sub.ZC=1.

[0232] As can be learned from formula (37):

[00108]$\frac{1}{u}$

is a cyclic shift corresponding to the random access sequence when the Doppler frequency shift is one time a PRACH subcarrier spacing, that is, a length that is of a cyclic shift between the random access sequence received by the base station and the random access sequence sent by the UE and that exists when the Doppler frequency shift is one time a PRACH subcarrier spacing.

[0233] For example, if the random access sequence sent by the UE is x.sub.u(n), when the Doppler frequency shift is one time a PRACH subcarrier spacing, the random access sequence received by the base station is

[00109]$x_u\left(\left(n+\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right).Math..Math.\mathrm{or}.Math..Math.x_u\left(\left(n-\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right).$

[0234] As can be learned from formula (15): if there is a Doppler frequency shift mf between receive ends of the UE and the base station, in a time domain, the random access sequence received by the base station is a shift sequence of the random access sequence sent by the UE, and there is a fixed phase offset

[00110]$W^{\frac{-\mathrm{um}\left(1/u\right).Math.\left(m\left(1/u\right)+1\right)}{2}}$

(unrelated to n) between the two sequences. Similarly, for a Doppler frequency shift +mf, the random access sequence received by the base station in a time domain is also a shift sequence of the random access sequence sent by the UE. Details are not described herein again.

[0235] Property 2: When the Doppler frequency shift is relatively large, and the Doppler frequency shift f.sub.off is less than one time a PRACH subcarrier spacing f, related peak values may appear in three positions of sequence shifts

[00111]$\frac{1}{u},0,\mathrm{and}.Math.-\frac{1}{u}$

when sequences are correlated.

[0236] That is, for the ZC sequence x.sub.u(n) whose root is u, when the Doppler frequency shift f.sub.off is less than one time a PRACH subcarrier spacing f, and the random access sequence sent by the UE is x.sub.u(n), there is a peak value when the receive end of the base station uses a sequence x.sub.u(n),

[00112]$x_u\left(\left(n+\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),\mathrm{or}.Math..Math.x_u\left(\left(n-\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right)$

to correlate with the random access sequence sent by the UE.

[0237] It should be noted that, property 2 is determined through an experiment.

[0238] As can be learned from property 1 and property 2:

[0239] 1) When a Doppler frequency shift is f.sub.off=f+x, and 0<x<f, during receiving by the base station, peak values are generated in three positions of shifts

[00113]$-\frac{1}{u},-2.Math.\frac{1}{u},$

and 0.

[0240] That is, for the ZC sequence x.sub.u(n) whose root is u, when a Doppler frequency shift is f.sub.off=f+x (0<x<f), and the random access sequence sent by the UE is x.sub.u(n), there is a peak value when the receive end of the base station uses a sequence x.sub.u(n),

[00114]$x_u\left(\left(n+\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),\mathrm{or}.Math..Math.x_u\left(\left(n-\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right)$

to correlate with the random access sequence sent by the UE.

[0241] 2) When the Doppler frequency shift is f.sub.off=f+x, and 0<x<f, during receiving by the base station, peak values are generated in three positions of shifts

[00115]$-\frac{1}{u},-2.Math.\frac{1}{u},$

and 0.

[0242] That is, for the ZC sequence x.sub.u(n) whose root is u, when the Doppler frequency shift is f.sub.off=f+x (0<x<f), and the random access sequence sent by the UE is x.sub.u(n), there is a peak value when the receive end of the base station uses a sequence x.sub.u(n),

[00116]$x_u\left(\left(n-\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),\mathrm{or}.Math..Math.x_u\left(\left(n-2.Math.\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right)$

to correlate with the random access sequence sent by the UE.

[0243] Therefore, when the Doppler frequency shift is greater than one time a PRACH subcarrier spacing f and is less than two times the PRACH subcarrier spacing, during receiving by the base station, peak values may be generated in five positions of shifts

[00117]$-\frac{1}{u},-2.Math.\frac{1}{u},0,\frac{1}{u},\mathrm{and}.Math..Math.2.Math.\frac{1}{u}.$

[0244] That is, for the ZC sequence x.sub.u(n) whose root is u, when the Doppler frequency shift is greater than one time a PRACH subcarrier spacing f and is less than two times the PRACH subcarrier spacing, and the random access sequence sent by the UE is x.sub.u(n), there may be a peak value when the receive end of the base station uses a sequence

[00118]$x_u\left(\left(n-2.Math..Math.\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),x_u\left(\left(n-\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),.Math.x_u\left(n\right),x_u\left(\left(n+\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right),\mathrm{or}.Math..Math.x_u\left(\left(n+2.Math..Math.\frac{1}{u}\right).Math.\mathrm{mod}.Math..Math.N_{\mathrm{ZC}}\right)$

to correlate with the random access sequence sent by the UE.

[0245] In this embodiment, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11), formulas (12) to (19), formulas (20) to (27), or formulas (28) to (35), to prevent the receive end of the base station from allocating, to another user, a sequence corresponding to five peak value points generated when the Doppler frequency shift is greater than one time a PRACH subcarrier spacing and is less than two times the PRACH subcarrier spacing, and thereby avoid interference between users that is caused by the Doppler frequency shift.

[0246] When

[00119]$\frac{1}{u}\frac{N_{\mathrm{ZC}}}{2},$

a sequence obtained when left cyclic shift is performed on the ZC sequence by

[00120]$\frac{1}{u}$

is the same as a sequence obtained when right cyclic shift is performed on the ZC sequence by

[00121]$N_{\mathrm{ZC}}-\frac{1}{u}.$

Therefore, in the present application,

[00122]$d_u=\{\begin{array}{cc}p& 0p<N_{\mathrm{ZC}}/2\\ N_{\mathrm{ZC}}-p& \mathrm{another}.Math..Math.\mathrm{value}\end{array},$

where

[00123]$p=\frac{1}{u}.$

As can be learned, d.sub.u is a cyclic shift corresponding to the random access sequence when the Doppler frequency shift is one time a PRACH subcarrier spacing.

[0247] FIG. 3 is a schematic diagram of scenario 1 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisfies

[00124]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}}\left(\mathrm{or}.Math..Math.\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u\frac{2}{7}.Math.N_{\mathrm{ZC}}\right).$

As shown in FIG. 3, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00125]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,$

where N.sub.CS indicates a quantity of cyclic shifts that are occupied by a user. For example, a sequence length is N.sub.ZC, and a user occupires N.sub.CS shifts. When the Doppler frequency shift is not considered, a maximum of N.sub.ZC/N.sub.CS users are simultaenously supported to simultaneously send the random access sequence.

[0248] n.sub.shift.sup.RA also indicates a quantity of users that can be distinguished in a group. From a perspective of a system, n.sub.shift.sup.RA users can be distinguished in a group. From a perspective of a UE side, one UE may select a maximum of n.sub.shift.sup.RA sequence shifts in a group.

[0249] It should be noted that, for the ZC sequence whose sequence length is N.sub.ZC, when the Doppler frequency shift is not considered and N.sub.CS=0, the AC sequence may have N.sub.ZC candidate sequence shifts, which respectively correspond to cyclic shift values 0 to N.sub.ZC1. For example, if the ZC sequence whose root is u is marked as x.sub.u(n), when the cyclici shift value is 0, a generated sequence thereof is x.sub.u(n). When the cyclic shift value is 1, a generated sequence thereof is x.sub.u(n+1). When the Doppler frequency shift is not considered and N.sub.CS is greater than 0, there may be N.sub.ZC/N.sub.CS candidate sequence shifts, which respectively correspond to cyclic shift values Y*N.sub.CS, where Y is an integer greater than or equal to 0 and less than N.sub.ZC/N.sub.CS1.

[0250] When the Doppler frequency shift is greater than one time a PRACH subcarrier spacing and is less than two times the PRACH subcarrier spacing, first user equipment generates a random access sequence according to a first cyclic shift value and sends the random access sequence to the base station. When the base station detects, by using a sequence corresponding to five cyclic shift values, the random access sequence sent by the first user equipment, there may be a peak value, and differences between the cyclic shift values and the first cyclic shift value are respectively 0, d.sub.u, d.sub.u, 2d.sub.u, and d.sub.u. Therefore, to avoid interference between the first user equipment and another user equipment, none of candidate sequence shifts corresponding to the five cyclic shift values can be allocated to the another user equipment. In addition, for the base station side, this is equivalent to that the candidate sequence shifts corresponding to the five cyclic shift values are all allocated to the first user equipment. That is, as shown in FIG. 3, sequence shifts (that is, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+1, 1.sub.1, and 1.sub.+2) related to 1 are used as candidate sequence shifts of a same group of UEs, and sequence shifts (that is, sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2) related to 2 are used as candidate sequence shifts of a same group of UEs.

[0251] In addition, because the differences between the five cyclic shift values and the first cyclic shift value are respectively 0, d.sub.u, d.sub.u, 2d.sub.u, and 2d.sub.u, it can also be learned that, for first UE in a first group of UEs, an initial sequence shift of sequence shifts that are occupied by 1.sub.0 is a cyclic shift value of the first UE in the first group of UEs. For first UE in a second group of UEs, an initial sequence shift of sequence shifts that are occupied by 2.sub.0 is a cyclic shift value of the first UE in the second group of UEs.

[0252] d.sub.start=4d.sub.uN.sub.ZC+n.sub.shift.sup.RA.Math.N.sub.CS indicates a cyclic shift distance between neighboring groups, as shown by filling patterns of lattice patterns in FIG. 3.

[00126]$n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.$

[0253] indicates a quantity of groups in a sequence whose sequence length is N.sub.ZC. As shown in FIG. 3, a quantity of groups is 2 (that is, the first group and the second group).

[00127]${\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right)$

[0254] indicates a quantity of UE candidate sequence shifts in the last length that is insufficient for a group. The quantity of UE candidate sequence shifts in the last length that is insufficient for a group is 0 in FIG. 3.

[0255] n.sub.shift.sup.RA=min(d.sub.un.sub.group.sup.RA.Math.d.sub.start, 4d.sub.uN.sub.ZCn.sub.shift.sup.RAN.sub.CS)/N.sub.CS indicates a quantity of UE candidate sequence shifts in first remaining sequence shifts, where the first remaining sequence shift is shown by filling patterns of stripes slanting towards left in FIG. 3.

[0256] .sub.shift.sup.RA=((1min(1,n.sub.shift.sup.RA))(d.sub.un.sub.group.sup.RA.Math.d.sub.start)+min(1,n.sub.shift.sup.RA) (4d.sub.uN.sub.ZCn.sub.shift.sup.RAN.sub.CS))/N.sub.CSn.sub.shift.sup.RA indicates a quantity of UE candidate sequence shifts in second remaining sequence shifts, where the second remaining sequence shift is shown by filling patterns of stripes slanting towards right in FIG. 3.

[0257] d.sub.start=N.sub.ZC3d.sub.u+n.sub.group.sup.RA.Math.d.sub.start+n.sub.shift.sup.RAN.sub.CS indicates a cyclic first shift value of a first UE candidate sequence shift in the first remaining sequence shifts, and is identified by an arrow X in FIG. 3.

[0258] .sub.start=N.sub.ZC2d.sub.u+n.sub.group.sup.RA.Math.d.sub.start+n.sub.shift.sup.RAN.sub.CS indicates a cyclic shift value of a first UE candidate sequence shift in the second remaining sequence shifts, and is identified by an arrow Y in FIG. 3.

[0259] For example, when N.sub.ZC=839, N.sub.CS=18, and d.sub.u=222, a corresponding scenario may be shown in FIG. 3.

[0260] It should be noted that, filling patterns of round point patterns in FIG. 3 are used to synchronously indicate one of five shift sequences occupied by a group, to more easily describe how to allocate each group.

[0261] FIG. 4 is a schematic diagram of scenario 2 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisifes

[00128]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}}\left(\mathrm{or}.Math..Math.\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u\frac{2}{7}.Math.N_{\mathrm{ZC}}\right).$

As shown in FIG. 4, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00129]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,$

where N.sub.CS indicates a quantity of cyclic shifts that are occupied by a user.

[0262] It should be noted that, in FIG. 4 and FIG. 3, physical meanings of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start and formulas that need to be satisfied are all the same. Details are not described herein again.

[0263] d.sub.start is shown by filling patterns of lattice patterns in FIG. 4, n.sub.shift.sup.RA is shown by filling patterns of stripes slanting towards left in FIG. 4, and d.sub.start is identified by an arrow X in FIG. 4.

[0264] In FIG. 4, n.sub.group.sup.RA is 2, n.sub.shift.sup.RA is 0, and .sub.shift.sup.RA is 0, and .sub.start is 0 (corresponding to that .sub.shift.sup.RA is 0).

[0265] For example, when N.sub.ZC=839, N.sub.CS=22, and d.sub.u=221, this may correspond to the scenario shown in FIG. 4.

[0266] It should be noted that, filling patterns of round point patterns in FIG. 4 are used to synchronously indicate one of five shift sequences occupied by one group, to more easily describe how to allocate each group.

[0267] FIG. 5 is a schematic diagram of scenario 3 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisifes

[00130]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}}\left(\mathrm{or}.Math..Math.\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u\frac{2}{7}.Math.N_{\mathrm{ZC}}\right).$

As shown in FIG. 5, sequence shifts that are occupied by 1.sub.01, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00131]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math.,$

where N.sub.CS indicates a quantity of cyclic shifts that are occupied by a user.

[0268] It should be noted that, in FIG. 5 and FIG. 3, physical meanings of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start and formulas that need to be satisfied are all the same. Details are not described herein again.

[0269] d.sub.start shown by filling patterns of lattice patterns in FIG. 5, n.sub.shift.sup.RA is shown by filling patterns of stripes slanting towards left in FIG. 5, and d.sub.start is identified by an arrow X in FIG. 5.

[0270] In FIG. 5, n.sub.group.sup.RA is 2, .sub.shift.sup.RA is 0, and .sub.start is 0 (corresponding to that .sub.shift.sup.RA is 0).

[0271] In FIG. 5, n.sub.shift.sup.RA may be 1. That is, five candidates sequence shifts corresponding to filling patterns of characters A (which may correspond to 0), B (which may correspond to +d.sub.u), C (which may correspond to +2d.sub.u), D (which may correspond to d.sub.u), and E (which may correspond to 2d.sub.u) are used as a new candidate sequence shift and are allocated to UE.

[0272] For example, when N.sub.ZC=839, N.sub.CS=18, and d.sub.u=220, this may correspond to the scenario shown in FIG. 5.

[0273] It should be noted that, filling patterns of round point patterns in FIG. 5 are used to synchronously indicate one of five shift sequences occupied by one group, to more easily describe how to allocate each group.

[0274] FIG. 6 is a schematic diagram of scenario 4 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisfies

[00132]$\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3}.Math.\left(\mathrm{or}.Math..Math.\frac{2}{7}.Math.N_{\mathrm{ZC}}<d_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3}\right).$

As shown in FIG. 6, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00133]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math..$

[0275] It should be noted that, in FIG. 6 FIG. 3 and n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, and n.sub.shift.sup.RA have same physical meanings, and only formulas that need to be satisfied are different. An analysis process is similar to that of FIG. 3. Details are not described herein again.

[0276] d.sub.start=N.sub.ZC3d.sub.u+n.sub.shift.sup.RA.Math.N.sub.CS indicates a cyclic shift distance between neighboring groups, and is shown by filling patterns of lattice patterns in FIG. 6.

[00134]$n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.$

[0277] indicates a quantity of groups in a sequence whose sequence length is N.sub.ZC. As shown in FIG. 6, a quantity of groups is 2.

[00135]${\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{4.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right)$

[0278] indicates a quantity of UE candidate sequence shifts in the last length that is insufficient for a group. As shown in FIG. 6, the quantity of UE candidate sequence shifts in the last length that is insufficient for a group may be 1. That is, five candidate sequence shifts corresponding to filling patterns of characters A, B, C, D, and E are used as a new candidate sequence shift and are allocated to UE.

[0279] n.sub.shift.sup.RA=min(d.sub.un.sub.group.sup.RA.Math.d.sub.start, N.sub.ZC3d.sub.un.sub.shift.sup.RAN.sub.CS)/N.sub.CS indicates a quantity of UE candidate sequence shifts in first remaining sequence shifts. The first remaining sequence shift is shown by filling patterns of stripes slanting towards left in FIG. 6.

[0280] .sub.shift.sup.RA=0 indicates that a quantity of UE candidate sequence shifts in second remaining sequence shifts is 0.

[0281] d.sub.start=d.sub.u+n.sub.group.sup.RA.Math.d.sub.start+n.sub.shift.sup.RAN.sub.CS indicates a cyclic shift value of a first UE candidate sequence shift in the first remaining sequence shifts, and is identified by an arrow X in FIG. 6.

[0282] .sub.start=0 (corresponding to .sub.shift.sup.RA=0).

[0283] For example, when N.sub.ZC=839, N.sub.CS=22, and d.sub.u=264, this may correspond to the scenario shown in FIG. 6.

[0284] It should be noted that, filling patterns of round point patterns in FIG. 6 are used to synchronously indicate one of five shift sequences occupied by one group, and filling patterns of vertical line patterns are used to synchronously indicate sequence shifts that are occupied by filling patterns of characters, to more easily describe how to allocate each group.

[0285] FIG. 7 is a schematic diagram of scenario 5 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisfies

[00136]$\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3}.Math.\left(\mathrm{or}.Math..Math.\frac{2}{7}.Math.N_{\mathrm{ZC}}<d_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3}\right).$

As shown in FIG. 7, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00137]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-3.Math.d_u}{N_{\mathrm{CS}}}.Math.,$

where N.sub.CS indicates a quantity of cyclic shifts that are occupied by a user.

[0286] It should be noted that, in FIG. 7 and FIG. 6, physical meanings of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start and formulas that need to be satisfied are all the same. Details are not described herein again.

[0287] d.sub.start is shown by filling patterns of lattice patterns in FIG. 7, n.sub.shift.sup.RA is shown by filling patterns of stripes slanting towards left in FIG. 7, and d.sub.start is identified by an arrow X in FIG. 7.

[0288] In FIG. 7, n.sub.group.sup.RA is 2, n.sub.shift.sup.RA is 0, .sub.shift.sup.RA is 0, and .sub.start is 0 (corresponding to that .sub.shift.sup.RA is 0).

[0289] For example, when N.sub.ZC=839, N.sub.CS=22, and d.sub.u=261, this may correspond to the scenario shown in FIG. 7.

[0290] It should be noted that, filling patterns of round point patterns in FIG. 7 are used to synchronously indicate one of five shift sequences occupied by one group, to more easily describe how to allocate each group.

[0291] FIG. 8 is a schematic diagram of scenario 6 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisfies

[00138]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math.N_{\mathrm{ZC}}}{5}.Math.\left(\mathrm{or}.Math..Math.\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u\frac{2.Math.N_{\mathrm{ZC}}}{5}\right).$

As shown in FIG. 8, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00139]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}}{N_{\mathrm{CS}}}.Math..$

[0292] It should be noted that, in FIG. 8 and FIG. 3, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, and n.sub.shift.sup.RA have same physical meanings, and only formulas that need to be satisfied are different. An analysis process is similar to that of FIG. 3. Details are not described herein again.

[0293] d.sub.start=3d.sub.uN.sub.ZC+n.sub.shift.sup.RA.Math.N.sub.CS indicates a cyclic shift dist ance between neighboring groups, and is shown by filling patterns of lattice patterns in FIG. 8.

[00140]$n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{d_u}{d_{\mathrm{start}}}.Math.$

[0294] indicates a quantity of groups in a sequence whose sequence length is N.sub.ZC. As shown in FIG. 8, the quantity of groups is 2.

[00141]${\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{N_{\mathrm{ZC}}-2.Math.d_u-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right)$

[0295] indicates a quantity of UE candidate sequence shifts in the last length that is insufficient for a group. As shown in FIG. 8, the quantity of UE candidate sequence shifts in the last length that is insufficient for a group may be 1. That is, five candidate sequence shifts corresponding to filling patterns of characters A, B, C, D, and E are used as a new candidate sequence shift and are allocated to UE.

[0296] n.sub.shift.sup.RA=0 indicates at a quantity of UE candidate sequence shifts in first remaining sequence shifts is 0.

[0297] .sub.shift.sup.RA=0 indicates that a quantity of UE candidate sequence shifts in second remaining sequence shifts is 0.

[0298] d.sub.start=0 (corresponding to n.sub.shaft.sup.RA=0).

[0299] .sub.start=0 (corresponding to .sub.shift.sup.RA=0).

[0300] For example, when N.sub.ZC=839, N.sub.CS=22, and d.sub.u=300, this may correspond to the scenario shown in FIG. 8.

[0301] FIG. 9 is a schematic diagram of scenario 7 according to an embodiment of the present application. In the figure, N=N.sub.ZC, and satisfies

[00142]$\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u<\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2}.Math.\left(\mathrm{or}.Math..Math.\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2}\right).$

As shown in FIG. 9, sequence shifts that are occupied by 1.sub.0, 1.sub.+1, 1.sub.+2, 1.sub.1, and 1.sub.+2 are used as a first group, and sequence shifts that are occupied by 2.sub.0, 2.sub.+1, 2.sub.+2, 2.sub.1, and 2.sub.+2 are used as a second group. A quantity of UE candidate sequence shifts in a group is

[00143]$n_{\mathrm{shift}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-2.Math.d_u}{N_{\mathrm{CS}}}.Math..$

[0302] It should be noted that, in FIG. 9 and FIG. 3, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, and n.sub.shift.sup.RA have same physical meanings, and only formulas that need to be satisfied are different. An analysis process is similar to that of FIG. 3. Details are not described herein again.

[0303] d.sub.start=2(N.sub.ZC2d.sub.u)+n.sub.shift.sup.RA.Math.N.sub.CS indicates a cyclic shift distance between neighboring groups, and is shown by filling patterns of lattice patterns in FIG. 9.

[00144]$n_{\mathrm{group}}^{\mathrm{RA}}=.Math.\frac{N_{\mathrm{ZC}}-d_u}{d_{\mathrm{start}}}.Math.$

[0304] indicates a quantity of groups in a sequence whose sequence length is N.sub.ZC. As shown in FIG. 9, the quantity of groups is 2.

[00145]${\stackrel{\_}{n}}_{\mathrm{shift}}^{\mathrm{RA}}=\max \left(.Math.\frac{3.Math.d_u-N_{\mathrm{ZC}}-n_{\mathrm{group}}^{\mathrm{RA}}.Math.d_{\mathrm{start}}}{N_{\mathrm{CS}}}.Math.,0\right)$

[0305] indicates a quantity of UE candidate sequence shifts in the last length that is insufficient for a group. As shown in FIG. 9, the quantity of UE candidate sequence shifts in the last length that is insufficient for a group may be 1. That is, five candidate sequence shifts corresponding to filling patterns of characters A, B, C, D, and E are used as a new candidate sequence shift and are allocated to UE.

[0306] n.sub.shift.sup.RA=0 indicates that a quantity of UE candidate sequence shifts in first remaining sequence shifts is 0.

[0307] .sub.shift.sup.RA=0 indicates that a quantity of UE candidate sequence shifts in second remaining sequence shifts is 0.

[0308] d.sub.start=0 (corresponding to n.sub.shift.sup.RA=0).

[0309] .sub.start=0 (corresponding to .sub.shift.sup.RA=0).

[0310] For example, when N.sub.ZC=839, N.sub.CS=22, and d.sub.u=383, this may correspond to the scenario shown in FIG. 9.

[0311] FIG. 10 is a flowchart of Embodiment 3 of a random access sequence generation method according to the present application. As shown in FIG. 10, the method in this embodiment may include:

[0312] Step 1001: UE receives notification signaling from a base station, where the notification signaling includes indication information, the indication information is used to instruct the UE to select a shift sequence numer from a range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the shift sequence number is an integer, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, n.sub.group.sup.RA is a quantity of groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in the last length that is insufficient for a group, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in first remaining sequence shifts, and .sub.shift.sup.RA is a quantity of UE candidate sequence shifts in second remaining sequence is shifts.

[0313] Step 1002: The UE selects a shift sequence number according to the notification signaling.

[0314] Specifically, the UE selects the shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1) according to the notification signaling.

[0315] Step 1003: The UE obtains a cyclic shift value according to the shift sequence number.

[0316] Step 1004: The UE generates a random access sequence according to the cyclic shift value.

[0317] In this embodiment, the UE selects the shift sequence number from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1) according to the notification signaling, so that after a quantity of UEs that can be distinguished is considered from a perspective of a group, quantities of UEs that can be further distinguished in other remaining discrete shift sequences obtained after grouping are further considered, thereby expanding a range from which a shift sequence number is selected.

[0318] Embodiment 4 of the random access sequence generation method is as follows:

[0319] Optionally, based on Embodiment 3 of the random access sequence generation method in the present application, step 1003 may specifically include:

[0320] obtaining, by the UE, the cyclic shift value C.sub.v according to the shift sequence number v by using formula (1), formula (2), or formula (3).

[0321] Optionally, in the case of v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1), the UE obtains the cyclic shift value C.sub.v by using formula (1);

[0322] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1), the UE obtains the cyclic shift value C.sub.v by using formula (2);

[0323] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the UE obtains the cyclic shift value C.sub.v by using formula (3).

[0324] Optionally, step 1004 may specifically include:

[0325] generating, by the UE, the random access sequence x.sub.u,C.sub.v(n) according to the cyclic shift value C.sub.v by using the following formula (36):

x.sub.u,C.sub.v(n)=x.sub.u((n+C.sub.v)mod N.sub.ZC)(36),

where

[0326] N.sub.ZC is a sequence length, and a ZC sequence whose root is u is defined as:

[00146]$x_u\left(n\right)=e^{-j.Math..Math.\frac{.Math..Math.\mathrm{un}\left(n+1\right)}{N_{\mathrm{ZC}}}},$

0nN.sub.ZC1.

[0327] In this embodiment, detailed descriptions of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start are the same as those in Embodiment 2 of the random access sequence generation method. Details are not described herein again.

[0328] FIG. 11 is a flowchart of Embodiment 5 of a random access sequence generation method according to the present application. As shown in FIG. 11, the method in this embodiment may include:

[0329] Step 1101: A base station selects a shift sequence number.

[0330] Specifically, the base station selects the shift sequence number v from a range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), where v is an integer, n.sub.shift.sup.RA is a quantity of user equipment UE candidate sequence shifts in a group, n.sub.group.sup.RA is a quantity of groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in the last length that is insufficient for a group, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in first remaining sequence shifts, and .sub.shift.sup.RA is a quantity of UE candidate sequence shifts in second remaining sequence shifts.

[0331] Step 1102: The base station obtains a cyclic shift value according to the shift sequence number.

[0332] Specifically, the base station obtains the cyclic shift value C.sub.v according to the shift sequence number v by using the following formula (1), formula (2), or formula (3):

C.sub.v=d.sub.offset+d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1);

C.sub.v=d.sub.offset+d.sub.start+(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA)N.sub.CS(2);

C.sub.v=d.sub.offset+.sub.start +(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA)N.sub.CS(3),

where

[0333] d.sub.offset is a shift offset, d.sub.start is a cyclic shift distance between neighboring groups, n.sub.shaft.sup.RA is a quantity of UE candidate sequence shifts in a group, N.sub.CS is a quantity of cyclic shifts that are occupied by a user, d.sub.start is a cyclic shift value of a first UE candidate sequence shift in first remaining sequence shifts, and .sub.start is a cyclic shift value of a first UE candidate sequence shift in second remaining sequence shifts.

[0334] In this embodiment, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy forulas (20) to (27); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0335] It should be noted that, in this embodiment, detailed descriptions of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start are the asme as those in Embodiment 2 of the random access sequence generation method. Details are not described herein again.

[0336] Optionally, in the case of v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift calue C.sub.v by using formula (1);

[0337] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift value C.sub.v by using formula (2);

[0338] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), the base station obtains the cyclic shift value C.sub.v by using formula (3).

[0339] Optionally, in the case of

[00147]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u<\frac{2}{7}.Math.N_{\mathrm{ZC}},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (R11), in the cse of

[00148]$\frac{2}{7}.Math.N_{\mathrm{ZC}}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19).

[0340] Alternatively, in the case of

[00149]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{4}{d}_u\frac{2}{7}.Math.N_{\mathrm{ZC}},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11), in the case of

[00150]$\frac{2}{7}.Math.N_{\mathrm{ZC}}<d_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{3},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19).

[0341] Optionally, in the case of

[00151]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u<\frac{2.Math.N_{\mathrm{ZC}}}{5},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27), in the case of

[00152]$\frac{2.Math.N_{\mathrm{ZC}}}{5}{d}_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0342] Alternatively, in the case of

[00153]$\frac{N_{\mathrm{ZC}}+N_{\mathrm{CS}}}{3}{d}_u\frac{2.Math.N_{\mathrm{ZC}}}{5},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27), in the case of

[00154]$\frac{2.Math.N_{\mathrm{ZC}}}{5}<d_u\frac{N_{\mathrm{ZC}}-N_{\mathrm{CS}}}{2},$

n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0343] In this embodiment, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start that satisfy formulas (4) to (11), formulas (12) to (19), formulas (20) to (27), or formulas (28) to (35), are used, and the shift sequence number is selected from the range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1), thereby expanding a range from which a shift sequence number is selected.

[0344] FIG. 12 is a flowchart of Embodiment 6 of a random access sequence generation method according to the present application. As shown in FIG. 12, the method in this embodiment may include:

[0345] Step 1201: UE selects a shift sequence number.

[0346] Specifically, the UE selects the shift sequence number v from a range of 0 to (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA+.sub.shift.sup.RA1).

[0347] v is an integer, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, n.sub.group.sup.RA is a group quantity of groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in the last length that is insufficient for a group, n.sub.shfit.sup.RA is a quantity of UE candidate sequence shifts in first remaining sequence shifts, and .sub.shift.sup.RA is a quantity of UE candidate sequence shifts in second remaining sequence shifts.

[0348] Step 1202: The UE obtains a cyclic shift value according to the shift sequence number.

[0349] Specifically, the UE obtains the cyclic shift value C.sub.v according to the shift sequence number v by using the following formula (1), formula (2), or formula (3):

C.sub.v=d.sub.offset+d.sub.startv/n.sub.shift.sup.RA+(v mod n.sub.shift.sup.RA)N.sub.CS(1);

C.sub.v=d.sub.offset+d.sub.start+(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA)N.sub.CS(2);

C.sub.v=d.sub.offset+.sub.start+(vn.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA)N.sub.CS(3),

where

[0350] d.sub.offset is a shift offset, d.sub.start is a cyclic shift distance between neighboring groups, n.sub.shift.sup.RA is a quantity of UE candidate sequence shifts in a group, N.sub.CS is a quantity of cyclic shifts that are occupied by a user, d.sub.start is a cyclic shift value of a first UE candidate sequence shift in the first remaining sequence shifts, and .sub.start is a cyclic shift value of a first UE candidate sequence shift in the second remaining sequence shifts.

[0351] Step 1203: The UE generates a random access sequence according to the cyclic shift value.

[0352] Specifically, the UE generates the random access sequence x.sub.u,C.sub.v(n) according to the cyclic shift value C.sub.v by using the following formula (36):

x.sub.u,C.sub.v(n)=x.sub.u((n+C.sub.v)mod N.sub.ZC)(36),

where

[0353] N.sub.ZC is a sequence length, and a ZC sequence whose root is u is defined as:

[00155]$x_u\left(n\right)=e^{-j.Math..Math.\frac{.Math..Math.\mathrm{un}\left(n+1\right)}{N_{\mathrm{ZC}}}},$

0nN.sub.ZC.

[0354] In this embodiment, n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (4) to (11); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (12) to (19); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (20) to (27); or n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start satisfy formulas (28) to (35).

[0355] It should be noted that, in this embodiment, detailed descriptions of n.sub.shift.sup.RA, d.sub.start, n.sub.group.sup.RA, n.sub.shift.sup.RA, n.sub.shift.sup.RA, .sub.shift.sup.RA, d.sub.start, and .sub.start sare the same as those in Embodiment 2 of the random access sequence generation method. Details are not desribed herein again.

[0356] Optionally, in the case of v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift calue C.sub.v by using formula (1);

[0357] in the case of (n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA1)<v(n.sub.shift.sup.RAn.sub.group.sup.RA+n.sub.shift.sup.RA+n.sub.shift.sup.RA1), the base station obtains the cyclic shift value C.sub.v by using formula (2);