Method and transmitter for allocating resources to terminal in telecommunication system
10873943 ยท 2020-12-22
Assignee
Inventors
Cpc classification
H04L5/0007
ELECTRICITY
H04W72/0453
ELECTRICITY
H04L27/26025
ELECTRICITY
H04W72/20
ELECTRICITY
H04L27/2666
ELECTRICITY
H04L27/26035
ELECTRICITY
H04L5/0039
ELECTRICITY
International classification
Abstract
The invention relates to allocating resources in a carrier when several subcarrier spacing configurations coexists, and more particularly to avoid or at least reduce the loss of resources when introducing guard bands to avoid inter-numerology interferences. The invention proposes to start the allocation of resource blocks to a terminal on a different subcarrier than the first subcarrier. Therefore the invention proposes a method to allocate such resource blocks to a terminal.
Claims
1. A method for allocating resources to a terminal in a telecommunication system comprising at least a carrier comprising several subcarriers, said carrier supporting at least one subcarrier spacing configuration Afo and one subcarrier spacing configuration f.sub.1, with f.sub.1=q.Math.f.sub.0, q being a strictly positive integer, said method comprising: a) selecting the subcarrier spacing configuration f.sub.1; b) determining a number L of resource blocks having subcarriers of said subcarrier spacing configuration f.sub.1; c) allocating to said terminal subcarriers among the subcarriers of the carrier of subcarrier spacing configurations f.sub.1, having their frequencies: greater or equal to a frequency, namely f.sub.start, being the lowest frequency among frequencies of subcarriers of subcarrier spacing configuration f.sub.1 having a frequency higher than or equal to f.sub.ref+m.Math.N.Math.f.sub.1+k.Math.N.Math.f.sub.0, f.sub.ref being the lowest frequency among the subcarriers that are allowable for subcarrier spacing f.sub.1 in the carrier, k being an integer greater or equal to 1 and lesser or equal to (q1), N being the number of subcarriers in a resource block, m being an integer greater or equal to 0 and lesser than a maximum number of resource blocks, allowable in the carrier, having subcarriers of subcarrier spacing configuration f.sub.1; lesser or equal to a frequency f.sub.ref+m.Math.N.Math.f.sub.1+(L.Math.N1).Math.f.sub.1, namely f.sub.last, wherein k is determined such as f.sub.startf.sub.near is greater than G, G being a strictly positive threshold, and f.sub.near being a frequency of a subcarrier with a subcarrier spacing configuration different from f.sub.1, said subcarrier having the highest frequency among frequencies of subcarriers allocated in the carrier having subcarrier spacing configurations different from f.sub.1 and having lower frequencies than f.sub.ref+(m+1).Math.N.Math.f.sub.1.
2. The method according to claim 1, wherein m is determined such as at least one subcarrier of subcarrier spacing configurations f.sub.1, having a frequency of at least f.sub.ref+m.Math.N.Math.f.sub.1 and at the most f.sub.ref+(m+1).Math.N.Math.f.sub.1f.sub.1, can be allocated to the terminal.
3. The method according to claim 1, wherein the subcarrier spacing configuration f.sub.0 is the smallest subcarrier spacing configuration among the subcarrier spacing configuration supported by the carrier.
4. The method according to claim 1, wherein said number L, L1, satisfies to:
q.Math.L+NRB.sub.start.sup.(0)N.sub.RB.sup.(0) where: N.sub.RB.sup.(0) is a maximum number of resource blocks comprising N subcarriers of the subcarrier spacing configuration f.sub.0 that are allowable in said carrier, NRB.sub.start.sup.(0) is a maximum number of resource blocks comprising N subcarriers of the subcarrier spacing configuration f.sub.0 that are allowable in said carrier, said resource blocks having their subcarriers frequencies lower than said frequency f.sub.start.
5. The method according to claim 4, further comprising sending to said terminal allocation information based on the subcarriers allocated to the terminal.
6. The method according to claim 5, wherein the allocation information based on the subcarriers allocated to the terminal, is a resource indication value, RIV, which is an integer and a function of L and NRB.sub.start.sup.(0).
7. The method according to claim 6, wherein said RIV function is an injective function of any couple comprising L and NRB.sub.start.sup.(0) values.
8. The method according to claim 6, wherein said RIV is a surjective function among the integers from 0 to the maximum value taken by RIV.
9. The method according to claim 6, wherein said RIV is defined by:
10. The method according to claim 6, wherein said RIV is defined by:
11. The method according to claim 6, wherein said RIV is defined by:
S.sub.l=N.sub.RB.sup.(0)q*l+1.
12. The method according to claim 1, wherein said RIV is defined by:
13. A non-transitory computer-readable medium having stored there on a computer program product comprising code instructions to perform the method according to claim 1, when said instructions are run by a processor.
14. A transmitter comprising a processor for allocating resources to a terminal in a telecommunication system comprising at least a carrier comprising several subcarriers, said carrier supporting at least one subcarrier spacing configuration f.sub.0 and one subcarrier spacing configuration f.sub.1, with f.sub.1=q.Math.f.sub.0, q being a strictly positive integer, said transmitter being configured to perform: a) selecting the subcarrier spacing configuration f.sub.1; b) determining a number L of resource blocks having subcarriers of said subcarrier spacing configuration f.sub.1; c) allocating to said terminal subcarriers among the subcarriers of the carrier of subcarrier spacing configurations f.sub.1, having their frequencies: greater or equal to a frequency, namely f.sub.start, being the lowest frequency among frequencies of subcarriers of subcarrier spacing configuration f.sub.1 having a frequency higher than or equal to f.sub.ref+m.Math.N.Math.f.sub.1+k.Math.N.Math.f.sub.0, f.sub.ref being the lowest frequency among the subcarriers that are allowable for subcarrier spacing f.sub.1 in the carrier, k being an integer greater or equal to 1 and lesser or equal to (q1), N being the number of subcarriers in a resource block, m being an integer greater or equal to 0 and lesser than a maximum number of resource block, allowable in the carrier, having subcarriers of subcarrier spacing configuration f.sub.1; lesser or equal to a frequency f.sub.ref+m.Math.N.Math.f.sub.1+(L.Math.N1).Math.f.sub.1, namely f.sub.last, wherein k is determined such as f.sub.startf.sub.near is greater than G, G being a strictly positive threshold, and f.sub.near being a frequency of a subcarrier with a subcarrier spacing configuration different from f.sub.1, said subcarrier having the highest frequency among frequencies of subcarriers allocated in the carrier having subcarrier spacing configurations different from f.sub.1 and having lower frequencies than f.sub.ref+(m+1).Math.N.Math.f.sub.1.
15. A transmitter according to claim 14, comprising a memory unit storing, for each couple of possible values of a number NRB.sub.start.sup.(0) and said L a unique resource indication value RIV, NRB.sub.start.sup.(0) being a maximum number of resource blocks comprising N subcarriers of the subcarrier spacing configuration f.sub.0 that are allowable in said carrier, said resource blocks having their subcarriers frequencies lower than said frequency f.sub.start, and wherein said transmitter is further configured to: provide a RIV value based on a couple of L and NRB.sub.start.sup.(0) corresponding to the allocation of subcarriers performed by the transmitter, and transmit the RIV to the terminal.
16. A terminal, in a telecommunication system, comprising a processor to use allocated resources in a carrier, said resources having been allocated according to claim 1, comprises: a communication module configured to receive an allocation resource block information through a control channel, a processing module which is configured to determine the subcarriers that are allocated to said terminal according to the allocation resource block information, wherein the processing module is configured to determine said subcarriers of subcarrier spacing configurations f.sub.1 allocated to the terminal: as having their frequencies greater or equal to f.sub.start, and as having their frequencies lesser or equal to f.sub.last.
17. A terminal according to claim 16, wherein said terminal further comprises a memory unit storing for each couple of possible values of a number NRB.sub.start.sup.(0) and said L a unique resource indication value RIV, NRB.sub.start.sup.(0) being a maximum number of resource blocks comprising N subcarriers of the first subcarrier spacing configuration f.sub.0 that are allowable in said carrier, said resource blocks having their subcarriers frequencies lower than said frequency f.sub.start, and wherein said processing module is configured to read said memory unit and determine the couple values L and NRB.sub.start.sup.(0) and recover f.sub.start and f.sub.last, upon reception of an RIV value in said allocation resource block information.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1)
(2)
(3)
(4)
(5)
(6)
DESCRIPTION OF EMBODIMENTS
(7) Referring to
(8) The transmitter 1 comprises one communication module (COM_trans) 3, one processing module (PROC_trans) 4 and a memory unit (MEMO_trans) 5. The MEMO_trans 5 comprises a non-volatile unit which retrieves the computer program and a volatile unit which retrieves the allocation parameters. The PROC_trans which is configured to determine the resource allocation information, such as a RIV value, according to the resource blocks that are allocated to the terminal. The COM_trans is configured to transmit to the terminal the resource allocation information.
(9) The terminal comprises one communication module (COM_term) 6, one processing module (PROC_term) 7 and a memory unit (MEMO_term) 8. The MEMO_term 8 comprises a non-volatile unit which retrieves the computer program and a volatile unit which retrieves the parameters of the carrier and the resource allocation information. The PROC_term 7 is configured to determine the subcarriers that are allocated to the terminal according to the resource allocation information. The COM_term 6 is configured to receive from the transmitter a resource allocation information.
(10) In the following, only part of the carrier band or part of a pre-defined portion of the carrier band is represented.
(11) Referring to
(12) To a numerology and more specifically to a subcarrier spacing configuration corresponds a raster, in which the socket of the raster corresponds to the size of a resource block of the same numerology in the frequency domain. All the resource blocks are scheduled aligned on this raster. Each potential resource block aligned on the raster is indexed to an integer number. For example in the logical region each of the N.sub.RB virtual resource blocks is numbered from 0 to N.sub.RB1. Several scheme of allocation exist, for example in LTE/LTE-A resource allocation type 2 is a compact format indicating to a terminal a set of contiguously virtual resource blocks which are allocated to it for downlink or uplink transfer. Therefore a resource indication value (RIV) corresponding to the number NRB.sub.start of the first contiguous resource block RB.sub.start allocated to the terminal and a length L in terms of virtually contiguously allocated resource blocks, is sent to the terminal. The RIV may be defined by:
RIV=N.sub.RB(L1)+NRB.sub.start if (L1)N/2,
RIV=N.sub.RB(N.sub.RBL+1)+(N.sub.RB1NRB.sub.start), otherwise.
Where NRB.sub.start is the number corresponding to the position of RB.sub.start.
(13) The RIV value enables the terminal to decode the position of the first virtual resource block RB.sub.start which is allocated to it and the number of virtually contiguous resource blocks that are allocated to the terminal. Once RB.sub.start and L are decoded the terminal is able to define the resource blocks that where allocated to it. In the example of
(14) Referring to
(15)
It should be noted that for certain subcarrier spacing configurations one extra RB can exist if fractional RBs containing less than N subcarriers are allowed for example at band edge. For the numerical example {f.sub.0, f.sub.1, f.sub.2}={kHz, 30 kHz, 60 kHz} and with N=12 subcarriers per resource block. The boxes represent resource blocks containing 12 subcarriers in the frequency domain
(16) Like mentioned above, between two subcarriers of different subcarrier spacing configurations, equally to resource blocks of different subcarrier spacing configurations a guard band (represented on
(17) For this reason it is necessary to include a guard band between two resource block of two different numerologies. As shown in
(18) For the simplicity of the expose, in
(19) Referring to
(20) The situation is similar between the last subcarrier of the resource allocation of subcarrier spacing configuration f.sub.2 and the following subcarrier of subcarrier spacing configuration f.sub.1.
(21) More specifically the first subcarrier of the resource allocation of subcarriers of subcarrier spacing configuration f.sub.2 is made according to the raster of subcarrier spacing configuration f.sub.0. This enables to set the size of the guard band with a scale of N.Math.f.sub.0, which is more flexible than a scale of N.Math.f.sub.2. Therefore, the transmitter can determine a guard band of N.Math.f.sub.0, 2.Math.N.Math.f.sub.0 or 3.Math.N.Math.f.sub.0. It is important to notice that when a guard band is set, for instance k.Math.N.Math.f.sub.0, it is possible that no subcarrier of the subcarrier spacing configuration f.sub.2 exist at k.Math.N.Math.f.sub.0, this is the case when q.sub.2, such as f.sub.2=q.sub.2.Math.f.sub.0, is not a divisor of N. In this case the SC.sub.start of the resource allocation is the first subcarrier of the subcarrier spacing configuration f.sub.2 after the guard band.
(22) To allocate such a resource allocation the transmitter defines the number NRB.sub.start.sup.(0) of resource blocks of subcarrier spacing configuration f.sub.0 containing subcarriers with frequencies lower than the frequency of the end of the guard band. In addition the transmitter defines the number L, L1 corresponding to the resource block of subcarrier spacing configuration f.sub.2 (L.sup.(2) on
(23) Therefore a specific RIV is defined as a function of L and NRB.sub.start.sup.(0).
(24) For example:
(25)
Where r.sub.2 is the remainder of the division of N.sub.RB.sup.(0) by q.sub.2 (In the example of
(26) Referring to
(27) At step S11 the transmitter sends to the terminal parameters concerning the cell settings including the carrier bandwidth BW and information on supported numerologies. More specifically the transmitter sends to the terminal information allowing the terminal to know directly or deduce at least the following parameters: f.sub.0, f.sub.2, N.sub.RB.sup.(0).
(28) At step S12 the transmitter sends to the terminal the allocation parameters, for example, indications allowing the terminal to deduce which type of subcarriers (subcarrier spacing configuration of the resource blocks) will be allocated to the terminal and therefore which set of formulae or lookup table will be necessary to decode the RIV value, if several sets are possible.
(29) At step S13 the transmitter defines the contiguous subcarriers it allocates to the terminal.
(30) At step S14 the transmitter sends the RIV value through a control channel. The RIV value is calculated with the RIV formula mentioned above based on the contiguous subcarriers the transmitter allocates to the terminal.
(31) Referring to
(32) At step S21 the terminal receives from the transmitter the parameters concerning the cell settings including the carrier bandwidth BW and information on supported numerologies. More specifically the terminal receives from the transmitter information allowing the terminal to know directly or deduce at least the following parameters: f.sub.0, f.sub.2, N.sub.RB.sup.(0).
(33) At step S22 the terminal receives from the transmitter the allocation parameters, for example indications allowing the terminal to deduce which type of subcarriers (subcarrier spacing configuration of the resource blocks) will be allocated to it and therefore which set of formula or lookup table will be necessary to decode the RIV value, if several sets are possible.
(34) At step S23 the terminal receives from the transmitter through a control channel, the RIV value corresponding to the subcarriers allocated to the terminal.
(35) At step S24 based on: the knowledge of N.sub.RB.sup.(0) and q.sub.2=f.sub.2/f.sub.0=4, the terminal computes: r.sub.2 the remainder of the division of N.sub.RB.sup.(0) by 4; and
(36)
(37)
(38)
(39) Based on the values NRB.sub.start.sup.(0) and L, decoded by the terminal, the terminal can determine a unique f.sub.start and a unique f.sub.last as shown above.
(40) Of course, the present invention is not limited to the examples of embodiments described in details above, but encompasses also further alternative embodiments.
(41) For example the present invention refers to carrier band of a specific bandwidth but the invention can also be implemented on a pre-defined portion of the entire carrier band, more specifically the pre-defined portion seen by a terminal as the maximum band where its own resource allocation and control signaling can occur.