Decoding control information received over a control channel
A User Equipment (UE) receives a Physical Downlink Control Channel (PDCCH) at subframe k and decodes at the subframe k a set of PDCCH candidates including L control channel elements (CCEs). The L CCEs are contiguously located from a position given by using a variable of Y k and a modulo (N/L) operation, where N represents a total number of CCEs in the subframe k, Y k is defined by Y k =(A*Y k−1 )mod D, and A and D are predetermined constant values. When k=0, Y −1 is determined based on a UE identifier having 16-bits.
1. A method for decoding control information by a User Equipment (UE), the method comprising:
receiving a Physical Downlink Control Channel (PDCCH) at subframe k; and
decoding at the subframe k a set of PDCCH candidates including L control channel elements (CCEs),
wherein:
the L CCEs are contiguously located from a position given by using a variable of Y k and a modulo (N/L) operation,
N represents a total number of CCEs in the subframe k,
Y k is defined by Y k =(A*Y k−1 ) mod D,
A and D are predetermined constant values, and
when k=0, Y −1 is determined based on a UE identifier having 16-bits.
2. The method of claim 1 , wherein A and D are 39827 and 65537, respectively.
3. The method of claim 1 , wherein L is one of 1, 2, 4, and 8.
4. The method of claim 1 , wherein the L CCEs corresponding to a first PDCCH candidate among the set of PDCCH candidates of the search space at the subframe k are contiguously located from a position given by: L*{(Y k )mod(floor(N/L)}.
5. The method of claim 1 , wherein the L CCEs corresponding to a first PDCCH candidate among the set of PDCCH candidates of the search space at the subframe k are located at positions given by: L*{(Y k )mod(floor(N/L)}+i, where N represents a total number of CCEs in the subframe k, floor(N/L) represents a function to quantize N/L to a largest integer that is equal to or less than N/L, and i=0, . . . , L−1.
6. The method of claim 1 , wherein the UE identifier is associated with a Radio Network Temporary Identifier (RNTI) of the UE.
7. The UE in claim 6 , wherein the RNTI of the UE is either a Cell-RNTI or a Temporary Cell-RNTI.
8. A User Equipment (UE) for decoding control information, comprising:
receiving a Physical Downlink Control Channel (PDCCH) at subframe k; and
decoding at the subframe k a set of PDCCH candidates including L control channel elements (CCEs),
wherein:
the L CCEs are contiguously located from a position given by using a variable of Y k and a modulo (N/L) operation,
N represents a total number of CCEs in the subframe k,
Y k is defined by Y k =(A*Y k−1 ) mod D,
A and D are predetermined constant values, and
when k=0, Y −1 is determined based on a UE identifier having 16-bits.
9. The UE in claim 8 , wherein A and D are 39827 and 65537, respectively.
10. The UE in claim 8 , wherein L is one of 1, 2, 4, and 8.
11. The UE in claim 8 , wherein the L CCEs corresponding to a first PDCCH candidate among the set of PDCCH candidates of the search space at the subframe k are contiguously located from a position given by: L*{(Y k )mod(floor(N/L)}.
12. The UE in claim 8 , wherein the L CCEs corresponding to a first PDCCH candidate among the set of PDCCH candidates of the search space at the subframe k are located at positions given by: L*{(Y k )mod(floor(N/L)}+i, where N represents a total number of CCEs in the subframe k, floor(N/L) represents a function to quantize N/L to a largest integer that is equal to or less than N/L, and i=0, . . . , L−1.
13. The UE in claim 8 , wherein the UE identifier is associated with a Radio Network Temporary Identifier (RNTI) of the UE.
14. The UE in claim 13 , wherein the RNTI of the UE is either a Cell-RNTI or a Temporary Cell-RNTI.