OBTAINING CONTROL CHANNEL ELEMENTS OF PHYSICAL DOWNLINK CONTROL CHANNELS FOR CROSS-CARRIER SCHEDULING

• US 20140185537A1
• Filed: 06/11/2013
• Published: 07/03/2014
• Est. Priority Date: 01/03/2013
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Papasakellariou, Aris
• Granted Patent: US 9,185,716 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/003 Arrangements for allocating sub-channels of the transmission path
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/12 Wireless traffic scheduling
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 84/042 Public Land Mobile systems, e.g. cellular systems
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Methods and apparatus of a NodeB or a user equipment (UE) in communication with each other are provided. The NodeB transmits and the UE receives via a Physical Downlink Control Channel (PDCCH). Control Channel Elements (CCEs) corresponding to a PDCCH candidate are obtained based on n_CI, where n_CI is a carrier index.

Claims

1. A method for a base station (NodeB) to transmit to a User Equipment (UE) one or more Physical Downlink Control CHannels (PDCCHs) in a first carrier of a plurality of carriers during a Transmission Time Interval (TTI) k, wherein each PDCCH comprises an aggregation of L consecutive Control Channel Elements (CCEs), is transmitted in at least one Physical Resource Block (PRB) from a set p of N_p≧

2 PRBs, and schedules to the UE one of a Physical Downlink Shared CHannel (PDSCH) reception and a Physical Uplink Shared CHannel (PUSCH) transmission in a second carrier of the plurality of carriers, where C denotes a number of carriers, the first carrier and the second carrier being one of a same carrier and different carriers, the method comprising;

allocating, to the UE, a unique carrier indicator (n_CI) for each of the plurality of carriers, wherein n_CI=0, 1, . . . , C−

1;

determining a location for a first CCE of a first PDCCH candidate for scheduling the one of the PDSCH reception and the PUSCH transmission in the second carrier with indicator n_CI as L·

(Y_p,k+n_CI), wherein Y_p,k is an offset value that depends on the PRB set p and on the TTI k and is computed by the UE; and

transmitting, to the UE, a PDCCH scheduling the one of the PDSCH reception and the PUSCH transmission in the second carrier.

2. The method of claim 1, wherein locations of CCEs corresponding to a PDCCH candidate m_nCI for one of the plurality of carriers with indicator n_CI, m_nCI=0, . . . , M_p,nCI^(L)−

1, are obtained based on;

3. The method of claim 2, wherein for a same M_p,CI^(L)=M_p^(L) value for all carriers, the locations of CCEs corresponding to a PDCCH candidate m for one of the plurality of carriers with indicator n_CI, m=0, . . . , M_p^(L)−

1, are obtained based

4. The method of claim 2, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p for all values of n_CI=0, 1, . . . , C−

1, and for each carrier, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB.

5. The method of claim 2, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p/C for all values of n_CI=0, 1, . . . , C−

1, and for each of the plurality of carriers, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB than a location of each PDCCH candidate for a different one of the plurality of carriers.

6. The method of claim 1, wherein the PDCCH conveys a DCI format that includes a Carrier Indicator Field (CIF);

and

wherein the CIF has a CIF value indicating the second carrier of the one of the PDSCH reception and the PUSCH transmission if the respective PDCCH location at least partially overlaps with a candidate PDCCH location for scheduling the one of the PDSCH reception and the PUSCH transmission on a different one of the plurality of carriers and the CIF value is a fixed value otherwise.

7. The method of claim 6, wherein the fixed value is equal to all zeroes and the UE suspends the one of the PDSCH reception and the PUSCH transmission when it is expected by the UE that the CIF value will be equal to all zeroes and the CIF value in the DCI format will not be equal to all zeroes.

8. A method for a User Equipment (UE) to receive one or more Physical Downlink Control CHannels (PDCCHs) transmitted from a base station (NodeB) in a first carrier of a plurality of carriers during a Transmission Time Interval (TTI) k, wherein each PDCCH comprises an aggregation of L consecutive Control Channel Elements (CCEs), is received in at least one Physical Resource Block (PRB) from a set p of N_p≧

2 PRBs, and schedules to the UE one of a Physical Downlink Shared CHannel (PDSCH) reception and a Physical Uplink Shared CHannel (PUSCH) transmission in a second carrier of the plurality of carriers, where C denotes a number of carriers, the first carrier and the second carrier being one of a same carrier and different carriers, the method comprising;

allocating a unique carrier indicator n_CI=0, 1, . . . , C−

1 for each of the C carriers;

determining a location for a first CCE of a first PDCCH candidate for scheduling the one of the PDSCH reception and the PUSCH transmission in the second carrier with indicator n_CI as L·

(Y_p,k+n_CI) wherein Y_p,k is an offset value that depends on the PRB set p and on the TTI k and is computed by the UE; and

detecting a PDCCH scheduling the one of the PDSCH reception and the PUSCH transmission in the second carrier.

9. The method of claim 8, wherein locations of CCEs corresponding to a PDCCH candidate m_nCI for one of the C carriers with indicator n_CI, m_nCI=0, . . . , M_p,nCI^(L)−

1 are obtained based on;

10. The method of claim 9, wherein for a same M_p,nCI^(L)=M_p^(L) value for all carriers, the locations of CCEs corresponding to a PDCCH candidate m for one of the plurality of carriers with indicator n_CI, m=0, . . . , M_p^(L)−

1, are obtained based on;

11. The method of claim 9, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p for all values of n_CI=0, 1, . . . , C−

1, and for each carrier, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB.

12. The method of claim 9, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p/C for all values of and for each of the plurality of carriers, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB than a location of each PDCCH candidate for a different one of the plurality of carriers.

13. The method of claim 8, wherein the PDCCH conveys a DCI format that includes a Carrier Indicator Field (CIF);

and

wherein the CIF has a CIF value indicating the second carrier of the one of the PDSCH reception and the PUSCH transmission if the respective PDCCH location at least partially overlaps with a candidate PDCCH location for scheduling the one of the PDSCH reception and the PUSCH transmission on a different one of the plurality of carriers and the CIF value is a fixed value otherwise.

14. The method of claim 13, wherein the fixed value is equal to all zeroes and the UE suspends the one of the PDSCH reception and the PUSCH transmission when the UE expects the CIF value to be equal to all zeroes and the CIF value in the DCI format is not equal to all zeroes.

15. A base station (NodeB) apparatus configured to transmit to a User Equipment (UE) one or more Physical Downlink Control CHannels (PDCCHs) in a first carrier of plurality of carriers during a Transmission Time Interval (TTI) k, wherein each PDCCH comprises an aggregation of L consecutive Control Channel Elements (CCEs), is transmitted in at least one Physical Resource Block (PRB) from a set p of N_p≧

2 PRBs, and schedules to the UE one of a Physical Downlink Shared CHannel (PDSCH) reception and a Physical Uplink Shared CHannel (PUSCH) transmission in a second carrier of the plurality of carriers, where C denotes a number of carriers, the first carrier and the second carrier being one of a same carrier and different carriers, the apparatus comprising;

an allocator configured to allocate to the UE a unique carrier indicator n_CI=0, 1, . . . , C−

1 for each of the plurality of carriers;

a processor configured to determine a location for a first CCE of a first PDCCH candidate to schedule the one of the PDSCH reception and the PUSCH transmission in the second carrier with indicator n_CI as L·

(Y_p,k+n_CI) wherein Y_p,k is an offset value that depends on the PRB set p and on the TTI k and is computed by the UE; and

a transmitter configured to transmit, to the UE, a PDCCH scheduling the one of the PDSCH reception and the PUSCH transmission in one of the plurality of carriers.

16. The apparatus of claim 15, wherein locations of CCEs corresponding to a PDCCH candidate m_nCI for one of the plurality of carriers with indicator n_CI, m_nCI=0, . . . , M_p,nCI^(L)−

1, are obtained based on;

17. The apparatus of claim 16, wherein for a same M_p,nCI^(L)=M_p^(L) value for all carriers, the locations of CCEs corresponding to a PDCCH candidate m for one of the plurality of carriers with indicator n_CI, m=0, . . . , M_p^(L)−

1, are obtained based on

18. The apparatus of claim 16, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p for all values of n_CI=0, 1, . . . , C−

1, and for each carrier, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB.

19. The apparatus of claim 16, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p/C for all values of n_CI=0, 1, . . . , C−

1, and for each of the plurality of carriers, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB than a location of each PDCCH candidate for a different one of the plurality of carriers.

20. The apparatus of claim 15, wherein the PDCCH conveys a DCI format that includes a Carrier Indicator Field (CIF);

and

wherein the CIF has a CIF value indicating the second carrier of the one of the PDSCH reception and the PUSCH transmission if the respective PDCCH location at least partially overlaps with a candidate PDCCH location for scheduling the one of the PDSCH reception and the PUSCH transmission on a different one of the plurality of carriers and the CIF value is a fixed value otherwise.

21. A User Equipment (UE) configured to receive one or more Physical Downlink Control CHannels (PDCCHs) transmitted from a base station (NodeB) in a first carrier of a plurality of carriers during a Transmission Time Interval (TTI) k, wherein each PDCCH comprises an aggregation of L consecutive Control Channel Elements (CCEs), is received in at least one Physical Resource Block (PRB) from a set p of N_p≧

2 PRBs, and schedules to the UE apparatus one of a Physical Downlink Shared CHannel (PDSCH) reception and a Physical Uplink Shared CHannel (PUSCH) transmission in a second carrier of the plurality of carriers, where C denotes a number of carriers, the first carrier and the second carrier being one of a same carrier and different carriers, the apparatus comprising;

an allocator configured to allocate a unique carrier indicator n_CI=0, 1, . . . , C−

1 for each of the plurality of carriers;

a processor configured to determine a location for a first CCE of a first PDCCH candidate for scheduling the one of the PDSCH reception and the PUSCH transmission in the second carrier with indicator n_CI as L·

(Y_p,k+n_CI) wherein Y_p,k is an offset value that depends on the PRB set p and on the TTI k and is computed by the UE apparatus; and

a detector configured to detect a PDCCH scheduling the one of the PDSCH reception and the PUSCH transmission in one of the plurality of carriers.

22. The apparatus of claim 21, wherein locations of CCEs corresponding to a PDCCH candidate m_nCI for one of the plurality of carriers with indicator n_CI, m_nCI=0, . . . , M_p,nCI^(L)−

1, are obtained based on;

23. The apparatus of claim 22, wherein for a same M_p,nCI^(L)=M_p^(L) value for all carriers, the locations of CCEs corresponding to the PDCCH candidate m for one of the plurality of carriers with indicator n_CI, m=0, . . . , M_p^(L)−

1, are obtained based on;

24. The apparatus of claim 22, wherein for a PDCCH transmission in a same PRB, for M_p,n^(L)≦

N_p for all values of n_CI=0, 1, . . . , C−

1, and for each carrier, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB.

25. The apparatus of claim 22, wherein for a PDCCH transmission in a same PRB, for M_p,nCI^(L)≦

N_p/C for all values of n_CI=0, 1, . . . , C−

1, and for each of the plurality of carriers, a location of each PDCCH candidate for one of the plurality of carriers is in a different PRB than a location of each PDCCH candidate for a different one of the plurality of carriers.

26. The apparatus of claim 21, wherein the PDCCH conveys a DCI format that includes a Carrier Indicator Field (CIF);

and

wherein the CIF has a CIF value indicating the second carrier of the one of the PDSCH reception and the PUSCH transmission if the respective PDCCH location at least partially overlaps with a candidate PDCCH location for scheduling the one of the PDSCH reception and the PUSCH transmission on a different one of the plurality of carriers and the CIF value is a fixed value otherwise.

27. The apparatus of claim 26, wherein the fixed value is equal to all zeroes and the apparatus suspends the one of the PDSCH reception and the PUSCH transmission when the UE expects the CIF value to be equal to all zeroes and the CIF value in the DCI format is not equal to all zeroes.