Node and method for uplink scheduling and hybrid automatic repeat request timing

Abstract

Example embodiments presented herein are directed towards a base station, and corresponding method therein, for determining a control timing configuration. The control timing configuration provides a subframe timing for configuring PUSCH and uplink HARQ-ACK control timing for a cell serving a user equipment in a multiple cell communications network. The user equipment is served by a TDD based cell and a FDD based cell. Example embodiments are also directed towards a user equipment, and corresponding method therein, determining the control timing configuration discussed above.

Claims

1. A method, in a base station, for determining a control timing configuration, the control timing configuration providing a subframe timing setting for configuring a Physical Uplink Shared Channel, PUSCH, and a corresponding uplink Hybrid Automatic Repeat Request Acknowledgment, HARQ-ACK, control timing for a cell serving a user equipment in a multiple cell communications network, the user equipment being served by a Time Division Duplex, TDD, based cell, and a Frequency Division Duplex, FDD, based cell, the method comprising: determining the control timing configuration for a secondary cell based on a type of a scheduling cell, the secondary cell being the FDD based cell; implementing the control timing configuration for the PUSCH and the corresponding uplink HARQ-ACK control timing for the cell serving the user equipment; and if the cell serving the user equipment by being scheduled with the PUSCH is the FDD based cell and the type of the scheduling cell is the TDD based cell and HARQ-ACK is transmitted on the secondary cell, the determining further comprising: determining the control timing configuration to be configuration number 0 if a configuration number of the scheduling cell is 0; and if the configuration number of the scheduling cell is not 0, determining the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

2. A base station for determining a control timing configuration, the control timing configuration providing a subframe timing setting for configuring a Physical Uplink Shared Channel, PUSCH, and a corresponding uplink Hybrid Automatic Repeat Request Acknowledgment, HARQ-ACK, control timing for a cell serving a user equipment in a multiple cell communications network, the user equipment being served by a Time Division Duplex, TDD, based cell, and a Frequency Division Duplex, FDD, based cell, the base station comprising: processing circuitry configured to: determine the control timing configuration for a secondary cell based on a type of a scheduling cell, the secondary cell being the FDD based cell; and implement the control timing configuration for the PUSCH and the corresponding uplink HARQ-ACK control timing for the cell serving the user equipment; and if the cell serving the user equipment by being scheduled with the PUSCH is the FDD based cell and the type of the scheduling cell is the TDD based cell and HARQ-ACK is transmitted on the secondary cell, the determining further comprising: determining the control timing configuration to be configuration number 0 if a configuration number of the scheduling cell is 0; and if the configuration number of the scheduling cell is not 0, determining the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

3. A method, in a user equipment, for determining a control timing configuration, the control timing configuration providing a subframe timing setting for configuring a Physical Uplink Shared Channel, PUSCH, and a corresponding uplink Hybrid Automatic Retransmission Repeat Acknowledgment, HARQ-ACK, control timing for a cell serving the user equipment in a multiple cell communications network, the user equipment being served by a Time Division Duplex, TDD, based cell, and a Frequency Division Duplex, FDD, based cell, the method comprising: determining the control timing configuration for a secondary cell based on a type of a scheduling cell, the secondary cell being the FDD based cell; and implementing the control timing configuration for the PUSCH and the corresponding uplink HARQ-ACK control timing for the cell serving the user equipment; and if the cell serving the user equipment by being scheduled with the PUSCH is the FDD based cell and the type of the scheduling cell is the TDD based cell and HARQ-ACK is transmitted on the secondary cell, the determining further comprising: determining the control timing configuration to be configuration number 0 if a configuration number of the scheduling cell is 0; and if the configuration number of the scheduling cell is not 0, determining the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

4. A user equipment for determining a control timing configuration, the control timing configuration providing a subframe timing setting for configuring a Physical Uplink Shared Channel, PUSCH, and a corresponding uplink Hybrid Automatic Repeat Request Acknowledgment, HARQ-ACK, control timing for a cell serving the user equipment in a multiple cell communications network, the user equipment being served by a Time Division Duplex, TDD, based cell, and a Frequency Division Duplex, FDD, based cell, the user equipment comprising: processing circuitry configured to: determine the control timing configuration for a secondary cell based on a type of a scheduling cell, the secondary cell being the FDD based cell; and implement the control timing configuration for the PUSCH and the corresponding uplink HARQ-ACK control timing for the cell serving the user equipment; and if the cell serving the user equipment by being scheduled with the PUSCH the FDD based cell and the type of the scheduling cell is the TDD based cell and HARQ-ACK is transmitted on the secondary cell, the determining further comprising: determining the control timing configuration to be configuration number 0 if a configuration number of the scheduling cell is 0; and if the configuration number of the scheduling cell is not 0, determining the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing will be apparent from the following more particular description of the example embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the example embodiments.

(2) FIG. 1 is an illustrative example of frequency and time division duplex;

(3) FIG. 2 is an illustrative example of an uplink/downlink time/frequency structure for LTE in the case of FDD and TDD;

(4) FIG. 3 is an illustrative example of the different uplink/downlink TDD configurations;

(5) FIGS. 4A and 4B illustrate an example of PUSCH scheduling and feedback timing for a configuration 1 and configuration 2 cell, respectively, without the use of cross carrier scheduling;

(6) FIG. 5 illustrates an example of control timing scheduling for a FDD based PCell and scheduling cell and a TDD based SCell and scheduled cell, wherein the TDD based scheduled cell follows a FDD control timing configuration, according to some of the example embodiments;

(7) FIG. 6 illustrates an example control timing scheduling for a FDD based PCell and scheduling cell and a TDD based SCell and scheduled cell, wherein the TDD based scheduled cell follows its own control timing configuration, according to some of the example embodiments;

(8) FIGS. 7 and 8 illustrate example control timing scheduling for a TDD based PCell and scheduling cell and a FDD based SCell and scheduled cell, wherein the FDD based scheduled cell follows the configuration timing of the TDD based PCell, according to some of the example embodiments;

(9) FIGS. 9 and 10 illustrate example control timing scheduling for a TDD based PCell and scheduling cell and a FDD based SCell and scheduled cell, wherein the FDD based scheduled cell follows its own configuration timing, according to some of the example embodiments;

(10) FIG. 11 illustrates an example of subframe hierarchy, according to some of the example embodiments;

(11) FIGS. 12 and 13 illustrate example control timing scheduling for a TDD based PCell and scheduling cell and a FDD based SCell and scheduled cell, wherein the FDD based scheduled cell follows a configuration timing of configuration 0 or 6 based on the subframe hierarchy of FIG. 11, according to some of the example embodiments;

(12) FIGS. 14 and 15 illustrate example control timing scheduling for a TDD based PCell and scheduling cell and a FDD based SCell and scheduled cell, wherein the FDD based scheduled cell follows a configuration timing according to revised tables, according to some of the example embodiments;

(13) FIG. 16 is an illustrative example of an example base station configuration, according to some of the example embodiments;

(14) FIG. 17 is an illustrative example of a user equipment configuration, according to some of the example embodiments;

(15) FIG. 18 is a flow diagram depicting example operations which may be taken by the base station of FIG. 16, according to some of the example embodiments; and

(16) FIG. 19 is a flow diagram depicting example operations which may be taken by the user equipment of FIG. 17, according to some of the example embodiments.

DETAILED DESCRIPTION

(17) In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular components, elements, techniques, etc. in order to provide a thorough understanding of the example embodiments. However, the example embodiments may be practiced in other manners that depart from these specific details. In other instances, detailed descriptions of well-known methods and elements are omitted so as not to obscure the description of the example embodiments.

(18) As part of the development of the example embodiments presented herein, a problem will first be identified and discussed.

(19) Interband TDD Carrier Aggregation with Different UL-DL Configurations on Different Carries

(20) In LTE Release 10, carrier aggregation of TDD cells is specified with the restriction that the U/D configurations for all the aggregated cells are identical. The need to allow more flexible carrier aggregation of TDD cells is to be addressed in Release 11 of LTE.

(21) The U/D configurations of neighboring cells need to be compatible to avoid severe interference problems. However, there are cases where the neighboring cells are operated by different operators or different wireless systems. The LTE TDD cells adjacent to those neighboring systems are hence required to adopt certain compatible U/D configurations. As a result, an operator may have several TDD cells having different U/D configurations on different frequencies.

(22) To solve the HARQ control and A/N feedback timings in carrier aggregation systems with cells of different UL-DL configurations, WO2013/025143 and 3GPP TS 36.211 V11.1.0 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation (Release 11), taught that a user equipment is configured with at least one of two timing configuration numbers. The first timing configuration number is a PDSCH HARQ control timing configuration number for determining PDSCH HARQ A/N timings across all aggregated cells. The second timing configuration number is a PUSCH control timing configuration number for determining PUSCH scheduling and the corresponding HARQ A/N timings on PHICH across all aggregated cells.

(23) As an example to illustrate the mechanism discussed above, consider PUSCH A/N feedback timing for a user equipment configured with carrier aggregation but and self-scheduling with configuration 1 cell and a configuration 2 cell shown in FIG. 4A and FIG. 4B, respectively. As shown in FIG. 4A, table 3 may be utilized to determine the UL HARQ control timing for a configuration 1 cell. Utilizing the n-k calculation, it is determined that such HARQ A/N feedbacks for PUSCH is transmitted from subframes 2, 3, 7 and 8 to subframes 6, 9, 1 and 4, respectively. Similarly, for a configuration 2 cell, utilizing the n-k calculation, FIG. 4B illustrates HARQ A/N feedbacks for PUSCH are transmitted from subframes 2 and 7 to subframes 6 and 1, respectively.

(24) For a user equipment configured with these two serving cells with cross-carrier scheduling, the UL feedback is changed for the scheduled cell in some UL/DL configurations to allow more UL subframes to be scheduled. Examples of such scheduling are provided in WO2013/025143 and 3GPP TS 36.211 V11.1.0 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical channels and modulation (Release 11).

Overview of the Example Embodiments

(25) In current 3GPP standards, the possibility of a user equipment being served by an aggregated FDD and TDD carrier simultaneously is not discussed or addressed. Thus, at least one example object of the example embodiments presented herein is to provide mechanisms to provide uplink scheduling and HARQ control timing for a FDD and TDD carrier aggregated network.

(26) Therefore, some of the example embodiments presented herein are directed towards how to allocate the HARQ timing and scheduling timing for PUSCH transmission, for example, UL HARQ. According to some of the example embodiments, depending on which if either FDD or a certain UL/DL configuration for TDD is used, an applicable reference configuration is selected for the HARQ timing. An advantage of the example embodiments is the ability to provide a simple scheme to derive the subframes for the timing of HARQ and scheduling for TDD and FDD aggregation.

(27) The applicable scheduling and HARQ timing for a user equipment performing aggregation between a FDD carrier and a TDD carrier depends on which of the carriers the scheduling is performed from. In addition, what impacts the applicable timings are whether the user equipment is configured with cross-carrier scheduling or not. The example embodiments are mostly described from the basis of only aggregation between two carriers although it is assumed that the aggregation may also be extended to more than two carriers.

(28) In this section, the example embodiments will be illustrated in more detail by a number of examples. It should be noted that these examples are not mutually exclusive. Components from one example embodiment may be tacitly assumed to be present in another embodiment and a person skilled in the art may use any number of the example embodiments in other example embodiments.

(29) The example embodiments will be presented as follows. First, example embodiments directed towards the FDD based cell functioning as the scheduling cell, as described under the heading “The FDD based cell as the scheduling cell”. Examples of scheduling for a TDD based SCell and a FDD based PCell are provided under the subheadings “Scheduled SCell follows FDD timing” and “Scheduled SCell follows TDD timing”.

(30) Numerous example embodiments are directed towards the TDD based cell functioning as the scheduling cell as described under the heading “The TDD based cell as the scheduling cell”. Examples of such scheduling for the FDD based SCell and a TDD based PCell are provided under the subheadings “Scheduled SCell follows TDD timing”, “Scheduled SCell follows FDD timing”, “Scheduled SCell follows timing according to subframe hierarchy”, “FDD SCell scheduling based on revised tables” and “Cases where the PHICH is transmitted on the scheduled FDD cell”.

(31) Finally, example node configurations and example node operations are provided under the subheadings “Example node configuration” and “Example node operations”, respectively. It should be appreciated that in the example embodiments described herein, the scheduling cell may be the PCell or a different SCell. In the example embodiments described herein, it is SCell which is scheduled (i.e., the scheduled cell).

(32) The FDD Based Cell as the Scheduling Cell

(33) Scheduled SCell Follows FDD Timing

(34) According to some of the example embodiments, the HARQ-ACK for a PUSCH on a scheduled SCell is transmitted from the serving cell that carried the scheduling PDCCH/ePDCCH. The PUSCH scheduling and PHICH timings of a TDD SCell shall follow those for the FDD scheduling cell. Subframes which map toward a DL subframe on the SCell are excluded from the timing. Such example embodiments are illustrated in FIG. 5.

(35) FIG. 5 illustrates a FDD based cell as the primary cell and the scheduling cell. The secondary cell, which is the scheduled cell, is a TDD based cell with a configuration of 1. As shown in FIG. 5, HARQ-ACK for PUSCH is scheduled with a timing value of 4 for all subframes for a PUSCH. Thus, uplink subframes 7, 8, 2 and 3 of the TDD based cell are scheduled for HARQ-ACK to subframes 1, 2, 6 and 7, of the FDD based cell, respectively. It should be appreciated that scheduled HARQ-ACK timings that map to a downlink subframe on the secondary scheduled TDD based cell are excluded from feedback.

(36) Scheduled SCell Follows TDD Timing

(37) According to some of the example embodiments, the HARQ-ACK for a PUSCH on the scheduled SCell is transmitted from the scheduled SCell. The PUSCH scheduling and PHICH timings of a TDD SCell shall follow its own timings as defined by its own UL/DL configuration. Such example embodiments are illustrated in FIG. 6.

(38) FIG. 6 illustrates a FDD based cell as the primary and the scheduling cell and the secondary and scheduled cell as a TDD based cell with a configuration of 1. As illustrated, the scheduled cell follows HARQ-ACK timings according to table 3. Utilizing the n+k calculation, PUSCH from subframes 7, 8, 2 and 3 are scheduled for HARQ-ACK in subframes 1, 4, 6 and 9, respectively, in the TDD based cell.

(39) The TDD Based Call as the Scheduling Cell

(40) According to some of the example embodiments, the HARQ-ACK for a PUSCH on the scheduled SCell is transmitted from the serving cell that carried the scheduling PDCCH/ePDCCH.

(41) Scheduled SCell Follows TDD Timing

(42) According to some of the example embodiments, the PUSCH scheduling and PHICH timings of a FDD SCell shall follow those for the TDD scheduling cell. Such example embodiments are illustrated in FIG. 7 and FIG. 8.

(43) FIG. 7 illustrates a FDD based SCell which is also the scheduled cell. FIG. 7 further illustrates a TDD based PCell with a configuration of 1 which is also the scheduling cell. In FIG. 7, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. For the case of a TDD configuration 1 PCell and a FDD SCell, four SCell UL subframes are to be schedulable, specifically, subframes 2, 3, 7 and 8. These subframes are scheduled according to table 3 via the n+k calculation. Thus, as provided by table 3, HARQ-ACK timings for subframes 2, 3, 7 and 8 of the FDD based SCell are scheduled to subframes 6, 9, 1 and 4, respectively, of the TDD based PCell.

(44) FIG. 8 illustrates a FDD based SCell which is also the scheduled cell. FIG. 8 further illustrates a TDD based PCell with a configuration of 2 which is also the scheduling cell. In FIG. 8, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. For the case of a TDD configuration 2 PCell and a FDD SCell, two SCell UL subframes are schedulable, specifically, subframes 2 and 7. These subframes are scheduled according to table 3 via the n+k calculation. Thus, as provided by table 3, HARQ-ACK timing for subframes 2 and 7 of the FDD based SCell are scheduled to subframes 8 and 3, respectively, of the TDD based PCell.

(45) Scheduled SCell Follows FDD Timing

(46) According to some of the example embodiments, the PUSCH scheduling and PHICH timings of a FDD SCell shall follow its own timings. Specifically, the FDD SCell shall be scheduled with a timing value of 4 for all subframes for a PUSCH. It should be appreciated that FDD scheduling which maps to downlink subframes in the TDD based cell are excluded from PUSCH timing.

(47) FIG. 9 provides an illustrative example of such an embodiment. In FIG. 9, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As shown in FIG. 9, a TDD based PCell, which is functioning as the scheduling cell, with a configuration of 1 is aggregated with a FDD based SCell, which is functioning as the scheduled cell. In such a configuration, two SCell UL subframes may be scheduled, specifically, subframes 0 and 5. Therefore, utilizing the timing value of 4 for all subframes, the PHICH for subframes 0 and 5 of the FDD based SCell are scheduled to subframes 4 and 9 of the TDD based PCell. It should be appreciated that utilizing this example embodiment, a HARQ-ACK scheduling of the FDD based cell subframe 3 is not possible as the PHICH for subframe 3 would be scheduled to subframe 7 of the TDD based cell, which is an UL cell.

(48) FIG. 10 provides another illustrative example of PUSCH scheduling and PHICH timings in which a FDD SCell follows its own timing. In FIG. 10, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As shown in FIG. 10, a TDD based PCell, which is functioning as the scheduling cell, with a configuration of 2 is aggregated with a FDD based SCell, which is functioning as the scheduled cell. In such a configuration, six SCell UL subframes may be scheduled, specifically, subframes 4, 5, 7, 9, 0 and 2. Therefore, utilizing the timing value of 4 for all subframes, subframes 4, 5, 7, 9, 0 and 2 of the FDD based SCell are scheduled to subframes 8, 9, 1, 3, 4 and 6 of the TDD based PCell. It should be appreciated that utilizing this example embodiment, a HARQ-ACK scheduling of the FDD based cell subframe 3 is not possible as subframe 3 would be scheduled to subframe 7 of the TDD based cell, which is an UL cell.

(49) Scheduled SCell Follows Timing According to Subframe Hierarchy

(50) According to some of the example embodiments, the choice of which configuration the SCell shall use for determining HARQ control timing is based on a subframe hierarchy, as illustrated in FIG. 11. It should be appreciated that the hierarchical ordering of FIG. 11 is further described in WO2013/025143.

(51) The subframe hierarchy may be designed with the following principles:

(52) (1) The UL subframes in a TDD configuration are also UL subframes in those TDD configurations that can be corrected with upward arrows.

(53) For example, subframes 2 and 3 are UL subframes in configuration 4. These two subframes are also UL in configurations 3, 1, 6 and 0, all of which can be connected from configuration 4 with upward arrows. As a second example, subframes 2 and 7 are UL subframes in configuration 2. These two subframes are not both UL in configuration 3 because there is no upward arrow connecting the two configurations.

(54) (2) The DL subframes in a TDD configuration are also DL subframes in those TDD configurations that can be corrected with downward arrows.

(55) For example, subframe 0, 1, 5, 6 and 9 are DL subframes in configuration 6. These five subframes are also DL in configurations 1, 2, 3, 4 and 5, all of which can be connected from configuration 6 with downward arrows. As a second example, subframe 7 is a DL subframe in configuration 3 but not a DL subframe in configuration 2 because there is no downward arrow connecting the two configurations.

(56) With these design properties, the subframe hierarchy may provide the following utility:

(57) (1) Given a set of TDD configurations to be aggregated, a TDD configuration that can be connected from all of the given TDD configurations with upward arrows has the following two properties: The TDD configuration comprises UL subframes that are a superset of all UL subframes from all given TDD configurations. The TDD configuration comprises DL subframes that are available in all given TDD configurations.

(58) Given the subframe hierarchy described above, according to some of the example embodiments, the PUSCH scheduling and PHICH timings of a FDD SCell shall follow those defined for a UL/DL configuration 0 TDD cell. Alternatively, UL/DL configuration 6 could be used. The advantage of this example embodiment is that six (or alternatively five) UL subframes on the FDD SCell may always be scheduled. However, one example drawback may be that the PUSCH round trip time for the FDD SCell may become greater than 10 ms.

(59) FIG. 12 illustrates an example of FDD SCell scheduling based on the subframe hierarchy as illustrated in FIG. 11. In FIG. 12, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As shown in FIG. 12, the FDD based SCell, which functions as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 1, which functions as the scheduling cell. As illustrated, the FDD SCell provides HARQ-ACK timing via configuration 0 as provided in table 3. Thus, using the n+k calculation, subframes 2, 3, 4, 7, 8, and 9 of the FDD based SCell provide HARQ-ACK feedback to subframes 6, 0, 0, 1, 5 and 5, respectively, of the TDD based PCell.

(60) FIG. 13 illustrates another example of FDD SCell scheduling based on the subframe hierarchy as illustrated in FIG. 11. In FIG. 13, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As shown in FIG. 13, the FDD based SCell, which functions as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 2, which functions as the scheduling cell. As illustrated, the FDD SCell provides HARQ-ACK timing via configuration 0 as provided in table 3. Thus, using the n+k calculation, subframes 2, 3, 4, 7, 8, and 9 of the FDD based SCell provide HARQ-ACK feedback to subframes 6, 0, 0, 1, 5 and 5, respectively, of the TDD based PCell.

(61) FDD SCell Scheduling Based on Revised Tables

(62) According to some of the example embodiments FDD based SCells may be scheduled with the use of revised tables. Such revised tables may be provided with the use of a combination of the above explained embodiments.

(63) Thus, according to some of the example embodiments, the PUSCH scheduling and PHICH timings of a FDD SCell shall follow: (1) UL/DL configuration 1 as the UL timing reference configuration if the UL/DL configuration of the scheduling TDD cell is 2, 4 or 5; and (2) UL/DL configuration of the scheduling cell as the UL timing reference configuration if the UL/DL configuration of the scheduling TDD cell is 0, 1, 3 or 6. The power control of the PUSCH transmitted on the scheduled FDD Scell shall incorporate the transmit power control command transmitted within the scheduling DCI according to the above defined UL timing reference configuration.

(64) For a FDD SCell scheduled from a TDD UL/DL configurations 1-6 cell and normal HARQ operation, the user equipment shall upon detection of a PDCCH/ePDCCH with uplink DCI format and/or a PHICH transmission in subframe n intended for the user equipment, adjust the corresponding PUSCH transmission in subframe n+k, with k given in Table 5.

(65) For a FDD SCell scheduled from a TDD UL/DL configuration 0 cell and normal HARQ operation, the user equipment shall upon detection of a PDCCH/ePDCCH with uplink DCI format and/or a PHICH transmission in subframe n intended for the user equipment, adjust the corresponding PUSCH transmission in subframe n+k if the MSB of the UL index in the PDCCH/EPDCCH with uplink DCI format is set to 1 or PHICH is received in subframe n=0 or 5 in the resource corresponding to I.sub.PHICH=0 with k given in Table 5. If the LSB of the UL index in the DCI format 0/4 is set to 1 in subframe n or a PHICH is received in subframe n=0 or 5 in the resource corresponding to I.sub.PHICH=1 or PHICH is received in subframe n=1 or 6, the user equipment shall adjust the corresponding PUSCH transmission in subframe n+7. If both the MSB and LSB of the UL index in the PDCCH/ePDCCH with uplink DCI format are set in subframe n, the user equipment shall adjust the corresponding PUSCH transmission in both subframes n+k and n+7, with k given in Table 5.

(66) TABLE-US-00005 TABLE 5 Effective k for a FDD Scell scheduled from a TDD cell TDD UL/DL Configuration of the subframe number n scheduling cell 0 1 2 3 4 5 6 7 8 9 0 4 6 4 6 1 6 4 6 4 2 6 4 6 4 3 4 4 4 4 6 4 6 4 5 6 4 6 4 6 7 7 7 7 5

(67) For a FDD SCell scheduled from a TDD UL/DL configuration 1-6 cell, an HARQ-ACK received on the PHICH assigned to a user equipment in subframe i is associated with the PUSCH transmission in the subframe i-k as indicated by the following Table 6.

(68) For a FDD SCell scheduled from a TDD UL/DL configuration 0 cell, an HARQ-ACK received on the PHICH in the resource corresponding to I.sub.PHICH=0, assigned to a user equipment in subframe i is associated with the PUSCH transmission in the subframe i-k as indicated by the following Table 6. An HARQ-ACK received on the PHICH in the resource corresponding to I.sub.PHICH=1 assigned to a user equipment in subframe i is associated with the PUSCH transmission in the subframe i-6.

(69) TABLE-US-00006 TABLE 6 Effective k for HARQ-ACK for a FDD Scell received from the PHICH on a TDD scheduling cell TDD UL/DL Configuration of the subframe number i scheduling cell 0 1 2 3 4 5 6 7 8 9 0 7 4 7 4 1 4 6 4 6 2 4 6 4 6 3 6 6 6 4 4 6 4 6 5 4 6 4 6 6 6 4 7 4 6

(70) For PUSCH transmissions transmitted on a FDD serving cell and scheduled from a TDD serving cell c in subframe n, the user equipment shall determine the corresponding PHICH resource of serving cell c in subframe n+k.sub.PHICH, where k.sub.PHICH is given in Table 7.

(71) It is further given if there is no PHICH resource available in the determined subframe, the user equipment should generate a local HARQ-ACK for the PHICH transmission. It is further given that a retransmission of an HARQ process would occur if the user equipment in such a scenario would receive an UL grant that indicates a retransmission occasion.

(72) TABLE-US-00007 TABLE 7 Effective k.sub.PHICH for a FDD Scell scheduled from a TDD cell TDD UL/DL Configuration of the subframe index n scheduling cell 0 1 2 3 4 5 6 7 8 9 0 4 7 6 4 7 6 1 4 6 4 6 2 4 6 4 6 3 6 6 6 4 4 6 4 6 5 4 6 4 6 6 4 6 6 4 7

(73) Within the downlink control information (DCI) transmitted to the user equipment via PDCCH/EPDCCH for scheduling PUSCH, there is a transmit power control (TPC) command. For a PUSCH transmission at subframe i on a FDD SCell scheduled from a TDD cell, the TPC command from subframe i−K.sub.PUSCH should be incorporated, where K.sub.PUSCH is given in Table 8.

(74) TABLE-US-00008 TABLE 8 Effective K.sub.PUSCH for a FDD Scell scheduled from a TDD cell TDD UL/DL Configuration of the subframe number i scheduling cell 0 1 2 3 4 5 6 7 8 9 0 — — 6 7 4 — — 6 7 4 1 — — 6 4 — — — 6 4 — 2 — — 6 4 — — — 6 4 — 3 — — 4 4 4 — — — — — 4 — — 6 4 — — — 6 4 — 5 — — 6 4 — — — 6 4 — 6 — — 7 7 5 — — 7 7 —

(75) Cases where the PHICH is Transmitted on the Scheduled FDD Cell

(76) In this setup, the HARQ-ACK for a PUSCH on the scheduled SCell is transmitted on the scheduled cell. According to some of the example embodiments, the PUSCH scheduling and PHICH timings of a FDD SCell scheduled from a TDD cell shall follow: (1) UL/DL configuration 0 as the UL timing reference configuration if the UL/DL configuration of the scheduling TDD cell is 0; and (2) FDD PUSCH scheduling and PHICH timings if the UL/DL configuration of the scheduling TDD cell is 1-6. The power control of the PUSCH transmitted on the scheduled FDD Scell shall incorporate the transmit power control command transmitted within the scheduling DCI according to the FDD serving cell timing.

(77) For a FDD SCell scheduled from a TDD UL/DL configurations 1-6 cell and normal HARQ operation, the user equipment shall upon detection of a PDCCH/EPDCCH with uplink DCI format and/or a PHICH transmission in subframe n intended for the user equipment, adjust the corresponding PUSCH transmission in subframe n+k, with k given in Table 9.

(78) For a FDD SCell scheduled from a TDD UL/DL configuration 0 cell and normal HARQ operation, the user equipment shall upon detection of a PDCCH/EPDCCH with uplink DCI format and/or a PHICH transmission in subframe n intended for the user equipment, adjust the corresponding PUSCH transmission in subframe n+k if the MSB of the UL index in the PDCCH/EPDCCH with uplink DCI format is set to 1 or PHICH is received in subframe n=0 or 5 in the resource corresponding to I.sub.PHICH=0 with k given in Table 9. If the LSB of the UL index in the DCI format 0/4 is set to 1 in subframe n or a PHICH is received in subframe n=0 or 5 in the resource corresponding to I.sub.PHICH=1 or PHICH is received in subframe n=1 or 6, the user equipment shall adjust the corresponding PUSCH transmission in subframe n+7. If both the MSB and LSB of the UL index in the PDCCH/EPDCCH with uplink DCI format are set in subframe n, the user equipment shall adjust the corresponding PUSCH transmission in both subframes n+k and n+7, with k given in Table 9.

(79) TABLE-US-00009 TABLE 9 Effective k for a FDD Scell scheduled from a TDD cell TDD UL/DL Configuration of the subframe number n scheduling cell 0 1 2 3 4 5 6 7 8 9 0 4 6 4 6 1 4 4 4 4 4 4 2 4 4 4 4 4 4 4 4 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 4 4 4 4 4 4 4 4 4 6 4 4 4 4 4

(80) For a FDD SCell scheduled from a TDD UL/DL configuration 1-6 cell, an HARQ-ACK received on the PHICH assigned to a UE in subframe i is associated with the PUSCH transmission in the subframe i-k as indicated by the following Table 10.

(81) For a FDD SCell scheduled from a TDD UL/DL configuration 0 cell, an HARQ-ACK received on the PHICH in the resource corresponding to I.sub.PHICH=0, assigned to a user equipment in subframe i is associated with the PUSCH transmission in the subframe i-k as indicated by the following Table 10. An HARQ-ACK received on the PHICH in the resource corresponding to I.sub.PHICH=1 assigned to a user equipment in subframe i is associated with the PUSCH transmission in the subframe i-6.

(82) TABLE-US-00010 TABLE 10 Effective k for HARQ-ACK for a FDD Scell received from the PHICH on a TDD scheduling cell TDD UL/DL Configuration of the subframe number i scheduling cell 0 1 2 3 4 5 6 7 8 9 0 7 4 7 4 1 4 4 4 4 4 4 2 4 4 4 4 4 4 4 4 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 4 4 4 4 4 4 4 4 4 6 4 4 4 4 4

(83) For PUSCH transmissions transmitted on a FDD serving cell and scheduled from a TDD serving cell c in subframe n, the user equipment shall determine the corresponding PHICH resource of serving cell c in subframe n+k.sub.PHICH, where k.sub.PHICH is given in Table 11.

(84) TABLE-US-00011 TABLE 11 Effective k.sub.PHICH for a FDD SCell scheduled from a TDD cell TDD UL/DL Configuration of the subframe index n scheduling cell 0 1 2 3 4 5 6 7 8 9 0 4 7 6 4 7 6 1 4 4 4 4 4 4 2 4 4 4 4 4 4 4 4 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 5 4 4 4 4 4 4 4 4 4 6 4 4 4 4 4

(85) Within the downlink control information (DCI) transmitted to the user equipment via PDCCH/EPDCCH for scheduling PUSCH, there is a transmit power control (TPC) command. For a PUSCH transmission at subframe i on a FDD SCell scheduled from a TDD cell, the TPC command from subframe i−K.sub.PUSCH should be incorporated, where K.sub.PUSCH is given in Table 12.

(86) TABLE-US-00012 TABLE 12 Effective K.sub.PUSCH for a FDD SCell scheduled from a TDD cell TDD UL/DL Configuration of the subframe number i scheduling cell 0 1 2 3 4 5 6 7 8 9 0 — — 6 7 4 — — 6 7 4 1 4 — — 4 4 4 — — 4 4 2 4 — 4 4 4 4 — 4 4 4 3 4 4 4 4 4 4 — — — 4 4 4 4 4 4 4 4 — — 4 4 5 4 4 4 4 4 4 — 4 4 4 6 4 — — 4 4 4 — — — 4

(87) FIG. 14 is an illustrative example of FDD based SCell scheduling based on the revised tables presented above. In FIG. 14, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As illustrated in FIG. 14, a FDD based SCell, which functions as the scheduled cell, is aggregated with a TDD based PCell with a configuration number of 1, which functions as the scheduling cell. In the example embodiment illustrated in FIG. 14, table 11 is used to determine the HARQ-ACK feedback timing. Thus, utilizing the n+k calculation of table 11, subframes 4, 5, 8, 9, 0 and 3 of the FDD based scheduled cell are scheduled to subframes 8, 9, 2, 3, 4 and 7, respectively, of the FDD based scheduled cell.

(88) FIG. 15 is an illustrative another example of FDD based SCell scheduling based on the revised tables presented above. In FIG. 15, the solid lines indicate PUSCH scheduling timings and the dashed lines indicate PHICH timings. As illustrated in FIG. 15, a FDD based SCell, which functions as the scheduled cell, is aggregated with a TDD based PCell with a configuration number of 2, which functions as the scheduling cell. In the example embodiment presented in FIG. 15, table 11 is used to determine the HARQ-ACK feedback timing. Thus, utilizing the n+k calculation of table 11, subframes 4, 5, 7, 8, 9, 0, 1 and 2 of the FDD based scheduled cell are scheduled to subframes 8, 9, 1, 2, 3, 4, 5 and 6, respectively, of the FDD based scheduled cell.

(89) Example Node Configurations

(90) FIG. 16 illustrates an example node configuration of a base station 401 which may perform some of the example embodiments described herein. The base station 401 may comprise radio circuitry or a communication port 410 that may be configured to receive and/or transmit communication data, instructions, and/or messages. It should be appreciated that the radio circuitry or communication port 410 may comprise any number of transceiving, receiving, and/or transmitting units or circuitry. It should further be appreciated that the radio circuitry or communication port 410 may be in the form of any input or output communications port known in the art. The radio circuitry or communication port 410 may comprise RF circuitry and baseband processing circuitry (not shown).

(91) The base station 401 may also comprise a processing unit or circuitry 420 which may be configured to implement HARQ-ACK control timing as described herein. The processing circuitry 420 may be any suitable type of computation unit, for example, a microprocessor, digital signal processor (DSP), field programmable gate array (FPGA), or application specific integrated circuit (ASIC), or any other form of circuitry. The base station 401 may further comprise a memory unit or circuitry 430 which may be any suitable type of computer readable memory and may be of volatile and/or non-volatile type. The memory 430 may be configured to store received, transmitted, and/or measured data, device parameters, communication priorities, and/or executable program instructions, e.g., scheduling instructions. The memory 430 may also be configured to store any form of configuration tables as described herein.

(92) FIG. 17 illustrates an example node configuration of a user equipment 501 which may perform some of the example embodiments described herein. The user equipment 501 may comprise radio circuitry or a communication port 510 that may be configured to receive and/or transmit communication data, instructions, and/or messages. It should be appreciated that the radio circuitry or communication port 510 may comprise any number of transceiving, receiving, and/or transmitting units or circuitry. It should further be appreciated that the radio circuitry or communication port 510 may be in the form of any input or output communications port known in the art. The radio circuitry or communication port 510 may comprise RF circuitry and baseband processing circuitry (not shown).

(93) The user equipment 501 may also comprise a processing unit or circuitry 520 which may be configured to implement HARQ-ACK control timing, as described herein. The processing circuitry 520 may be any suitable type of computation unit, for example, a microprocessor, digital signal processor (DSP), field programmable gate array (FPGA), or application specific integrated circuit (ASIC), or any other form of circuitry. The user equipment 501 may further comprise a memory unit or circuitry 530 which may be any suitable type of computer readable memory and may be of volatile and/or non-volatile type. The memory 530 may be configured to store received, transmitted, and/or measured data, device parameters, communication priorities, and/or executable program instructions, e.g., scheduling instructions. The memory 530 may also be configured to store any form of configuration tables as described herein.

(94) Example Node Operations

(95) FIG. 18 is a flow diagram depicting example operations which may be performed by the base station 401 as described herein to implement HARQ-ACK control timing, as described herein. It should be appreciated that FIG. 18 comprises some operations which are illustrated with a solid border and some operations which are illustrated with a dashed border. The operations which are comprised in a solid border are operations which are comprised in the broadest example embodiment. The operations which are comprised in a dashed border are example embodiments which may be comprised in, or a part of, or are further operations which may be performed in addition to the operations of the broader example embodiments. It should be appreciated that these operations need not be performed in order. Furthermore, it should be appreciated that not all of the operations need to be performed. The example operations may be performed in any order and in any combination.

(96) The example operations of FIG. 18 describe a base station, and corresponding method, for determining a control timing configuration. The control timing configuration provides a subframe timing setting for configuration PUSCH and uplink HARQ-ACK control timing for a cell serving a user equipment in a multiple cell communications network. The user equipment is served by a TDD based cell and a FDD based cell.

(97) Operation 10

(98) The base station 401 is configured to determine a control timing configuration for a secondary cell. The secondary cell is one of the TDD based cell or the FDD based cell. The determination of the control timing configuration is based on a type of the scheduling cell. The type of the scheduling cell is either FDD or TDD. The processing circuitry 420 is configured to determine the control timing configuration for the secondary cell.

(99) Example Operation 12

(100) According to some of the example embodiments, the determining 10 may further comprise determining 12 the control timing configuration to comprise a transmission timing value of 4 for all subframes for a PUSCH, where downlink subframes of the scheduling cell which map to downlink subframes of the secondary cell are excluded from PUSCH timing. The processing circuitry 420 is configured to determine the control timing configuration to comprise a transmission timing value of 4 for all subframes for a PUSCH, where downlink subframes of the scheduling cell which map to downlink subframes of the secondary cell are excluded from PUSCH timing.

(101) According to some of the example embodiments, in example operation 12, the secondary cell may be either the FDD based cell or the TDD based cell. Furthermore, the scheduling cell may be the TDD based cell or the FDD based cell.

(102) An example of operation 12 is provided under at least the heading “The FDD based cell as the scheduling cell” and subheading “Scheduled SCell follows FDD timing”, as well as FIG. 5. As shown in FIG. 5, the TDD based SCell follows FDD timing, specifically, a timing value of 4 is utilized for all subframes for a PUSCH.

(103) A further example of operation 12 is provided under the heading “The TDD based cell as the scheduling cell” and subheading “Scheduled SCell follows FDD timing”, as well as FIGS. 9 and 10. As illustrated in FIGS. 9 and 10, the FDD based SCell follows its own timing, specifically, a timing value of 4 is utilized for all subframes for a PUSCH.

(104) Example Operation 14

(105) According to some of the example embodiments, the determining 10 may further comprise determining 14 the control timing configuration to be equivalent to a TDD configuration of the TDD based cell. The processing circuitry 420 is configured to determine the control timing configuration to be equivalent to a TDD configuration of the TDD based cell.

(106) According to some of the example embodiments, in example operation 14, the secondary cell may be either the FDD based cell or the TDD based cell. Furthermore, the scheduling cell may be the TDD based cell or the FDD based cell.

(107) An example of operation 14 is provided under at least the heading “The FDD based cell as the scheduling cell” and subheading “Scheduled SCell follows TDD timing”, as well as FIG. 6. As illustrated in FIG. 6, a TDD based SCell follows its own configuration. Thus, in the example provided in FIG. 6, the TDD based SCell follows control timing according to configuration 1, which is the configuration of the TDD based SCell.

(108) A further example of operation 14 is provided under at least the heading “The TDD based cell as the scheduling cell” and subheading “Scheduled SCell follows TDD timing”, as well as FIGS. 7 and 8. As shown in FIG. 7, the FDD based SCell follows the control timing according to the configuration of the TDD based PCell, which functions as the scheduling cell. Specifically, the FDD based SCell follows the control timing according to configuration 1, which is the configuration of the TDD based PCell. Similarly, in FIG. 8, the FDD based SCell follows control timing according to configuration 2, which is the configuration of the scheduling TDD based PCell.

(109) Example Operation 16

(110) According to some of the example embodiments, the secondary cell is the FDD based cell and the scheduling cell is the TDD based cell. According to such example embodiments, the determining 10 further comprises determining 16 the control timing configuration to be equivalent to a configuration number of 0 or 6. The processing circuitry 420 is configured to determine the control timing configuration to be equivalent to a configuration number of 0 or 6.

(111) Example operation 16 is further described under at least the heading “The TDD based cell as the scheduling cell” and the subheading “Scheduled SCell follows timing according to subframe hierarchy” and FIGS. 12 and 13. According to some of the example embodiments, scheduling based on a subframe hierarchy provides that either a configuration of 0 or 6 is chosen for scheduling the FDD based SCell. It should be appreciated that the choice of a configuration number of 0 or 6 is provided with respect to a subframe hierarchy as explained in FIG. 11.

(112) As shown in FIG. 12, a FDD based SCell, functioning as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 1, functioning as the scheduling cell. In the example provided in FIG. 12, the FDD based SCell is scheduled with a configuration of 0 as provided by the subframe hierarchy of FIG. 11.

(113) FIG. 13 illustrates a FDD based SCell, functioning as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 2, functioning as the scheduling cell. In the example provided in FIG. 13, the FDD based SCell is scheduled with a configuration of 0 as provided by the subframe hierarchy of FIG. 11.

(114) Example Operation 18

(115) According to some of the example embodiments, the scheduling cell is the TDD based cell and the secondary cell is the FDD based cell. According to such example embodiments, the determining 10 may further comprise determining 18 the control timing configuration to be configuration number 1 if a configuration number of the scheduling cell is 2, 4 or 5. The processing circuitry 420 is configure to determine the control timing configuration to be configuration number 1 if a configuration number of the scheduling cell is 2, 4 or 5.

(116) Example operation 18 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “FDD SCell scheduling based on revised tables” as well as tables 5-8. As illustrated in tables 5-8, for configurations 2, 4 and 5, the k values of configuration 1 have been provided from tables 1-4, respectively. All other configurations of tables 5-8 comprise the normal configurations as provided in tables 1-4, respectively. Thus, tables 5-8 are revised tables.

(117) Example Operation 20

(118) According to some of the example embodiments, the operation of determining 10 and the example operation of determining 18 may further comprise, if the configuration number of the scheduling cell is not 2, 4 or 5, determining 20 the control timing configuration to be equivalent to the configuration number of the scheduling cell. The processing circuitry 420 is configured to determine the control timing configuration to be equivalent to the configuration number of the scheduling cell.

(119) Example operation 20 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “FDD SCell scheduling based on revised tables” as well as tables 5-8. As illustrated in tables 5-8, for configurations 2, 4 and 5, the k values of configuration 1 have been provided from tables 1-4, respectively. All other configurations of tables 5-8 comprise the normal configurations as provided in tables 1-4, respectively. Thus, tables 5-8 are revised tables.

(120) Example Operation 22

(121) According to some of the example embodiments the scheduling cell is the TDD based cell and the secondary cell is the FDD based cell. According to such example embodiments, the HARQ-ACK is transmitted on the secondary cell. Accordingly, the determining 10 may further comprise determining 22 the control timing configuration to be configuration number 0 if the configuration of the scheduling cell is 0. The processing circuitry 420 is configured determine the control timing configuration to be configuration number 0 if the configuration of the scheduling cell is 0.

(122) Example operation 22 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “Cases where the PHICH is transmitted on the scheduled FDD cell” as well as tables 9-12. As illustrated in tables 9-12, for configuration 0, the k values of configuration 0 have been provided from tables 1-4, respectively. All other configurations of tables 9-12 comprise FDD timing values, specifically a timing value of 4 for all subframes for a PUSCH. It should be appreciated that the tables for configurations 1-6 are constructed in order to exclude downlink subframes of the FDD based cell to map to uplink subframes of the TDD based PCell (e.g., the scheduling cell). Thus, tables 9-12 are revised tables.

(123) Example Operation 24

(124) According to some of the example embodiments, the operation of determining 10 and the example operation of determining 22 further comprise, if the configuration number of the scheduling cell is not 0, determining 24 the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe. The processing circuitry 420 is configured to determine the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

(125) Example operation 24 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “Cases where the PHICH is transmitted on the scheduled FDD cell” as well as tables 9-12. As illustrated in tables 9-12, for configuration 0, the k values of configuration 0 have been provided from tables 1-4, respectively. All other configurations of tables 9-12 comprise FDD timing values, specifically a timing value of 4 for all subframes for a PUSCH. It should be appreciated that the tables for configurations 1-6 are constructed in order to exclude downlink subframes of the FDD based cell to map to uplink subframes of the TDD based PCell (e.g., the scheduling cell). Thus, tables 9-12 are revised tables.

(126) Operation 26

(127) The base station is further configured to implement the control timing configuration for PUSCH and uplink HARQ-ACK control timing for a cell serving the user equipment. The processing circuitry 420 is configured to implement the control timing configuration for PUSCH and uplink HARQ-ACK control timing for a cell serving the user equipment.

(128) Example Operation 28

(129) According to some of the example embodiments, the base station may be further configured to send, to the user equipment, the implemented control timing configuration via RRC signalling. The radio circuitry 410 is configured to send, to the user equipment, the implement control timing configuration via RRC signalling.

(130) FIG. 19 is a flow diagram depicting example operations which may be performed by the user equipment 501 as described herein to implement HARQ-ACK control timing, as described herein. It should be appreciated that FIG. 19 comprises some operations which are illustrated with a solid border and some operations which are illustrated with a dashed border. The operations which are comprised in a solid border are operations which are comprised in the broadest example embodiment. The operations which are comprised in a dashed border are example embodiments which may be comprised in, or a part of, or are further operations which may be performed in addition to the operations of the broader example embodiments. It should be appreciated that these operations need not be performed in order. Furthermore, it should be appreciated that not all of the operations need to be performed. The example operations may be performed in any order and in any combination.

(131) The example operations of FIG. 19 describe a user equipment, and corresponding method, for determining a control timing configuration. The control timing configuration provides a subframe timing setting for configuration PUSCH and uplink HARQ-ACK control timing for a cell serving a user equipment in a multiple cell communications network. The user equipment is served by a TDD based cell and a FDD based cell.

(132) Operation 30

(133) The user equipment 501 is configured to determine a control timing configuration for a secondary cell. The secondary cell is one of the TDD based cell or the FDD based cell. The determination of the control timing configuration is based on a type of the scheduling cell. The type of the scheduling cell is either FDD or TDD. The processing circuitry 520 is configured to determine the control timing configuration for the secondary cell.

(134) Example Operation 32

(135) According to some of the example embodiments, the determining 30 may further comprise determining 32 the control timing configuration to comprise a transmission timing value of 4 for all subframes for a PUSCH, where downlink subframes of the scheduling cell which map to downlink subframes of the secondary cell are excluded form PUSCH timing. The processing circuitry 520 is configured to determine the control timing configuration to comprise a transmission timing value of 4 for all subframes for a PUSCH, where downlink subframes of the scheduling cell which map to downlink subframes of the secondary cell are excluded from PUSCH timing.

(136) According to some of the example embodiments, according to example operation 32, the secondary cell may be either the FDD based cell or the TDD based cell. Furthermore, the scheduling cell may be the TDD based cell or the FDD based cell.

(137) An example of operation 32 is provided under at least the heading “The FDD based cell as the scheduling cell” and subheading “Scheduled SCell follows FDD timing”, as well as FIG. 5. As shown in FIG. 5, the TDD based SCell follows FDD timing, specifically, a timing value of 4 is utilized for all subframes for a PUSCH.

(138) A further example of operation 32 is provided under the heading “The TDD based cell as the scheduling cell” and subheading “Scheduled SCell follows FDD timing”, as well as FIGS. 9 and 10. As illustrated in FIGS. 9 and 10, the FDD based SCell follows its own timing, specifically, a timing value of 4 is utilized for all subframes for a PUSCH.

(139) Example Operation 34

(140) According to some of the example embodiments, the determining 30 may further comprise determining 34 the control timing configuration to be equivalent to a TDD configuration of the TDD based cell. The processing circuitry 520 is configured to determine the control timing configuration to be equivalent to a TDD configuration of the TDD based cell.

(141) According to some of the example embodiments, according to example operation 34, the secondary cell may be either the FDD based cell or the TDD based cell. Furthermore, the scheduling cell may be the TDD based cell or the FDD based cell.

(142) An example of operation 34 is provided under at least the heading “The FDD based cell as the scheduling cell” and subheading “Scheduled SCell follows TDD timing”, as well as FIG. 6. As illustrated in FIG. 6, a TDD based SCell follows its own configuration. Thus, in the example provided in FIG. 6, the TDD based SCell follows control timing according to configuration 1, which is the configuration of the TDD based SCell.

(143) A further example of operation 34 is provided under at least the heading “The TDD based cell as the scheduling cell” and subheading “Scheduled SCell follows TDD timing”, as well as FIGS. 7 and 8. As shown in FIG. 7, the FDD based SCell follows the control timing according to the configuration of the TDD based PCell, which functions as the scheduling cell. Specifically, the FDD based SCell follows the control timing according to configuration 1, which is the configuration of the TDD based PCell. Similarly, in FIG. 8, the FDD based SCell follows control timing according to configuration 2, which is the configuration of the scheduling TDD based PCell.

(144) Example Operation 36

(145) According to some of the example embodiments, the secondary cell is the FDD based cell and the scheduling cell is the TDD based cell. According to such example embodiments, the determining 30 further comprises determining 36 the control timing configuration to be equivalent to a configuration number of 0 or 6. The processing circuitry 520 is configured to determine the control timing configuration to be equivalent to a configuration number of 0 or 6.

(146) Example operation 36 is further described under at least the heading “The TDD based cell as the scheduling cell” and the subheading “Scheduled SCell follows timing according to subframe hierarchy” and FIGS. 12 and 13. According to some of the example embodiments, scheduling based on a subframe hierarchy provides that either a configuration of 0 or 6 is chosen for scheduling the FDD based SCell. It should be appreciated that the choice of a configuration number of 0 or 6 is provided with respect to a subframe hierarchy as explained in FIG. 11.

(147) As shown in FIG. 12, a FDD based SCell, functioning as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 1, functioning as the scheduling cell. In the example provided in FIG. 12, the FDD based SCell is scheduled with a configuration of 0 as provided by the subframe hierarchy of FIG. 11.

(148) FIG. 13 illustrates a FDD based SCell, functioning as the scheduled cell, is aggregated with a TDD based PCell with a configuration of 2, functioning as the scheduling cell. In the example provided in FIG. 13, the FDD based SCell is scheduled with a configuration of 0 as provided by the subframe hierarchy of FIG. 11.

(149) Example Operation 38

(150) According to some of the example embodiments, the scheduling cell is the TDD based cell and the secondary cell is the FDD based cell. According to such example embodiments, the determining 30 may further comprise determining 38 the control timing configuration to be configuration number 1 if a configuration number of the scheduling cell is 2, 4 or 5. The processing circuitry 520 is configured to determine the control timing configuration to be configuration number 1 if a configuration number of the scheduling cell is 2, 4 or 5.

(151) Example operation 38 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “FDD SCell scheduling based on revised tables” as well as tables 5-8. As illustrated in tables 5-8, for configurations 2, 4 and 5, the k values of configuration 1 have been provided from tables 1-4, respectively. All other configurations of tables 5-8 comprise the normal configurations as provided in tables 1-4, respectively. Thus, tables 5-8 are revised tables.

(152) Example Operation 40

(153) According to some of the example embodiments, the operation of determining 30 and the example operation of determining 38 may further comprise, if the configuration number of the scheduling cell is not 2, 4 or 5, determining 40 the control timing configuration to be equivalent to the configuration number of the scheduling cell. The processing circuitry 520 is configured to determine the control timing configuration to be equivalent to the configuration number of the scheduling cell.

(154) Example operation 40 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “FDD SCell scheduling based on revised tables” as well as tables 5-8. As illustrated in tables 5-8, for configurations 2, 4 and 5, the k values of configuration 1 have been provided from tables 1-4, respectively. All other configurations of tables 5-8 comprise the normal configurations as provided in tables 1-4, respectively. Thus, tables 5-8 are revised tables.

(155) Example Operation 42

(156) According to some of the example embodiments the scheduling cell is the TDD based cell and the secondary cell is the FDD based cell. According to such example embodiments, the HARQ-ACK is transmitted on the secondary cell. Accordingly, the determining 30 may further comprise determining 42 the control timing configuration to be configuration number 0 if the configuration of the scheduling cell is 0. The processing circuitry 520 is configured determine the control timing configuration to be configuration number 0 if the configuration of the scheduling cell is 0.

(157) Example operation 42 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “Cases where the PHICH is transmitted on the scheduled FDD cell” as well as tables 9-12. As illustrated in tables 9-12, for configuration 0, the k values of configuration 0 have been provided from tables 1-4, respectively. All other configurations of tables 9-12 comprise FDD timing values, specifically a timing value of 4 for all subframes for a PUSCH. It should be appreciated that the tables for configurations 1-6 are constructed in order to exclude downlink subframes of the FDD based cell to map to uplink subframes of the TDD based PCell (e.g., the scheduling cell). Thus, tables 9-12 are revised tables.

(158) Example Operation 44

(159) According to some of the example embodiments, the operation of determining 30 and the example operation of determining 42 further comprise, if the configuration number of the scheduling cell is not 0, determining 44 the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe. The processing circuitry 520 is configured to determine the control timing configuration to be a HARQ-ACK feedback timing value of 4 for a subframe in which a corresponding TDD subframe, for a same configuration number, is a downlink subframe.

(160) Example operation 44 is further described under at least the heading “The TDD based cell as the scheduling cell” and subheading “Cases where the PHICH is transmitted on the scheduled FDD cell” as well as tables 9-12. As illustrated in tables 9-12, for configuration 0, the k values of configuration 0 have been provided from tables 1-4, respectively. All other configurations of tables 9-12 comprise FDD timing values, specifically a timing value of 4 for all subframes for a PUSCH. It should be appreciated that the tables for configurations 1-6 are constructed in order to exclude downlink subframes of the FDD based cell to map to uplink subframes of the TDD based PCell (e.g., the scheduling cell). Thus, tables 9-12 are revised tables.

(161) Example Operation 46

(162) According to some of the example embodiments, the determining 30 may further comprise receiving, from the base station, the control timing configuration via RRC signalling. The radio circuitry 510 is configured to receive, from the base station, the control timing configuration via RRC signalling.

(163) Operation 48

(164) The user equipment is further configured to implement 48 the control timing configuration for PUSCH and uplink HARQ-ACK control timing for a cell serving the user equipment. The processing circuitry 520 is configured to implement the control timing configuration for PUSCH and uplink HARQ-ACK control timing for a cell serving the user equipment.

(165) It should be noted that although terminology from 3GPP LTE has been used herein to explain the example embodiments, this should not be seen as limiting the scope of the example embodiments to only the aforementioned system. Other wireless systems, comprising HSPA, WCDMA, WiMax, UMB, WiFi and GSM, may also benefit from the example embodiments disclosed herein.

(166) The description of the example embodiments provided herein have been presented for purposes of illustration. The description is not intended to be exhaustive or to limit example embodiments to the precise form disclosed, and modifications and variations are possible in light of the above teachings or may be acquired from practice of various alternatives to the provided embodiments. The examples discussed herein were chosen and described in order to explain the principles and the nature of various example embodiments and its practical application to enable one skilled in the art to utilize the example embodiments in various manners and with various modifications as are suited to the particular use contemplated. The features of the embodiments described herein may be combined in all possible combinations of methods, apparatuses, modules, systems, and computer program products. It should be appreciated that the example embodiments presented herein may be practiced in any combination with each other.

(167) It should be noted that the word “comprising” does not necessarily exclude the presence of other elements or steps than those listed and the words “a” or “an” preceding an element do not exclude the presence of a plurality of such elements. It should further be noted that any reference signs do not limit the scope of the claims, that the example embodiments may be implemented at least in part by means of both hardware and software, and that several “means”, “units” or “devices” may be represented by the same item of hardware.

(168) Also note that terminology such as user equipment should be considered as non-limiting. A wireless terminal or user equipment (UE) as the term is used herein, is to be broadly interpreted to comprise a radiotelephone having ability for Internet/intranet access, web browser, organizer, calendar, a camera, e.g., video and/or still image camera, a sound recorder, e.g., a microphone, and/or global positioning system (GPS) receiver; a personal communications system (PCS) user equipment that may combine a cellular radiotelephone with data processing; a personal digital assistant (PDA) that can comprise a radiotelephone or wireless communication system; a laptop; a camera, e.g., video and/or still image camera, having communication ability; and any other computation or communication device capable of transceiving, such as a personal computer, a home entertainment system, a television, etc. It should be appreciated that the term user equipment may also comprise any number of connected devices, wireless terminals or machine-to-machine devices.

(169) It should further be appreciated that the term dual connectivity should not be limited to a user equipment or wireless terminal being connected to only two base stations. In dual connectivity a wireless terminal may be connected to any number of base stations.

(170) The various example embodiments described herein are described in the general context of method steps or processes, which may be implemented in one aspect by a computer program product, embodied in a computer-readable medium, comprising computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may comprise removable and non-removable storage devices comprising, but not limited to, Read Only Memory (ROM), Random Access Memory (RAM), compact discs (CDs), digital versatile discs (DVD), etc. Generally, program modules may comprise routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

(171) In the drawings and specification, there have been disclosed exemplary embodiments. However, many variations and modifications can be made to these embodiments. Accordingly, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.