Method and apparatus of controlling for uplink scheduling and HARQ timing
The present invention relates to an apparatus and method for controlling an uplink (UL) scheduling and Hybrid Automatic Repeat reQuest (HARD) timing supported in a TDD-FDD CA environment. According to aspects of the present invention, in a TDD-FDD carrier aggregation deployment environment, an efficient UL scheduling/HARQ operation may be performed for a UE in which a cross-carrier scheduling is configured.
1. A method of a Hybrid Automatic Repeat reQuest (HARQ) process performed by a User Equipment (UE), the UE supporting a cross-carrier scheduling, the method comprising:
receiving cross-carrier scheduling information from a base station, the cross-carrier scheduling information indicating a cross-carrier scheduling between a Time Division Duplex (TDD) cell and a Frequency Division Duplex (FDD) cell; and
when the FDD cell is configured as a scheduled cell, which is scheduled by the TDD cell, executing, by the UE, a process comprising:
determining a first interval between an uplink (UL) grant and a Physical Uplink Shared Channel (PUSCH) and determining a second interval between the PUSCH and a Physical HARQ Indicator Channel (PHICH);
receiving the UL grant through the TDD cell, the UL grant being received in a first subframe of the TDD cell;
transmitting, from the UE, the PUSCH through the FDD cell, the PUSCH being responsive to the UL grant and transmitted in a second subframe of the FDD cell, the second subframe being determined based on the first subframe and the first interval; and
receiving a PHICH through the TDD cell, the PHICH being responsive to the PUSCH and transmitted in a third subframe of the TDD cell, the third subframe being determined based on the second subframe and the second interval,
wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the first interval is determined, for different values of integer m, such that a subframe m is determined as the second subframe if the first subframe is determined as a subframe m−4, and the second interval is determined, for the different values of integer m, such that a subframe m+6 is determined as the third subframe if the second subframe is determined as the subframe m.
2. The method of claim 1 , wherein an uplink/downlink configuration for the TDD cell comprises at least one of uplink/downlink configurations 0, 1, 2, 3, 4, 5, and 6 as shown in the following table:
Uplink/downlink
Subframe number
configuration
0
1
2
3
4
5
6
7
8
9
0
D
S
U
U
U
D
S
U
U
U
1
D
S
U
U
D
D
S
U
U
D
2
D
S
U
D
D
D
S
U
D
D
3
D
S
U
U
U
D
D
D
D
D
4
D
S
U
U
D
D
D
D
D
D
5
D
S
U
D
D
D
D
D
D
D
6
D
S
U
U
U
D
S
U
U
D,
where D denotes a downlink (DL) subframe, U denotes an uplink (UL) subframe, and S denotes a special subframe.
3. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 0.
4. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 3, 4, 5, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 1.
5. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 2, 3, 4, 5, 7, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 2.
6. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 3.
7. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 4.
8. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, 7, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 5.
9. The method of claim 2 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 3, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 6.
10. The method of claim 1 , further comprising:
determining the TDD cell as a scheduling cell to schedule the FDD cell; and
monitoring the TDD cell for receiving scheduling information of the FDD cell,
wherein a period of the HARQ process of the FDD cell is 10 ms.
11. A method of a Hybrid Automatic Repeat reQuest (HARQ) process performed by a base station, the base station supporting a cross-carrier scheduling, the method comprising:
transmitting cross-carrier scheduling information to a User Equipment (UE), the cross-carrier scheduling information indicating a cross-carrier scheduling between a Time Division Duplex (TDD) cell and a Frequency Division Duplex (FDD) cell; and
when the FDD cell is configured as a scheduled cell, which is scheduled by the TDD cell, executing, by the base station, a process comprising:
determining a first interval between an uplink (UL) grant and a Physical Uplink Shared Channel (PUSCH) and determining a second interval between the PUSCH and a Physical HARQ Indicator Channel (PHICH);
transmitting the UL grant through the TDD cell, the UL grant being received in a first subframe of the TDD cell;
receiving, from the UE, the PUSCH through the FDD cell, the PUSCH being responsive to the UL grant and transmitted in a second subframe of the FDD cell, the second subframe being determined based on the first subframe and the first interval; and
transmitting a PHICH through the TDD cell, the PHICH being responsive to the PUSCH and transmitted in a third subframe of the TDD cell, the third subframe being determined based on the second subframe and the second interval,
wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the first interval is determined, for different values of integer m, such that a subframe m is determined as the second subframe if the first subframe is determined as a subframe m−4, and the second interval is determined, for the different values of integer m, such that a subframe m+6 is determined as the third subframe if the second subframe is determined as the subframe m.
12. The method of claim 11 , wherein an uplink/downlink configuration for the TDD cell comprises at least one of uplink/downlink configurations 0, 1, 2, 3, 4, 5, and 6 as shown in the following table:
Uplink/downlink
Subframe number
configuration
0
1
2
3
4
5
6
7
8
9
0
D
S
U
U
U
D
S
U
U
U
1
D
S
U
U
D
D
S
U
U
D
2
D
S
U
D
D
D
S
U
D
D
3
D
S
U
U
U
D
D
D
D
D
4
D
S
U
U
D
D
D
D
D
D
5
D
S
U
D
D
D
D
D
D
D
6
D
S
U
U
U
D
S
U
U
D,
where D denotes a downlink (DL) subframe, U denotes an uplink (UL) subframe, and S denotes a special subframe.
13. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 0.
14. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 3, 4, 5, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 1.
15. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 2, 3, 4, 5, 7, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 2.
16. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 3.
17. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 4.
18. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 1, 2, 3, 4, 5, 7, 8, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 5.
19. The method of claim 12 , wherein when the FDD cell is the scheduled cell, which is scheduled by the TDD cell, the values of the subframe number m consist of 0, 3, 4, 5, and 9 when the TDD UL/DL configuration of the TDD cell corresponds to 6.
20. The method of claim 11 , further comprising:
determining the TDD cell as a scheduling cell to schedule the FDD cell,
wherein a period of the HARQ process of the FDD cell is 10 ms.
21. A method of a Hybrid Automatic Repeat reQuest (HARQ) process performed by a User Equipment (UE), the UE supporting a cross-carrier scheduling, the method comprising:
receiving cross-carrier scheduling information from a base station, the cross-carrier scheduling information indicating a cross-carrier scheduling between a Time Division Duplex (TDD) cell and a Frequency Division Duplex (FDD) cell; and
when the FDD cell is configured as a scheduled cell, which is scheduled by the TDD cell, executing, by the UE, a process comprising:
determining a first interval between an uplink (UL) grant through the TDD cell and a Physical Uplink Shared Channel (PUSCH) through the FDD cell and determining a second interval between the PUSCH through the FDD cell and a Physical HARQ Indicator Channel (PHICH) through the TDD cell;
receiving the UL grant in a first subframe of the TDD cell;
transmitting, from the UE, the PUSCH in a second subframe of the FDD cell, the PUSCH being responsive to the UL grant, and the second subframe being determined based on the first subframe and the first interval; and
receiving the PHICH in a third subframe of the TDD cell, the PHICH being responsive to the PUSCH, and the third subframe being determined based on the second subframe and the second interval,
wherein according to a TDD UL/DL configuration of the TDD cell, available values of the number m are determined such that the subframe (m−4) is a downlink subframe of the TDD cell or a special subframe of the TDD cell,
wherein when the subframe number m equals to values including 0, 4, 5, and 9, a subframe m is determined as the second subframe of the FDD cell when the first subframe of the TDD cell is a subframe (m−4), and
wherein when the subframe number m equals to values including 0, 4, 5, and 9, a subframe m+6 is determined as the third subframe of the TDD cell when the second subframe of the FDD cell is the subframe m.
22. The method of claim 21 , wherein according to a TDD UL/DL configuration of the TDD cell, available values of the subframe number m are determined such that the subframe (m−4) is a downlink subframe of the TDD cell or a special subframe of the TDD cell,
wherein for all of the available values of the number m, a subframe m is determined as the second subframe of the FDD cell when the first subframe of the TDD cell is a subframe (m−4), and
wherein for all of the available values of the number m, a subframe m+6 is determined as the third subframe of the TDD cell when the second subframe of the FDD cell is the subframe m.