Resource allocation for repetitions of transmissions in a communication system

1. A base station comprising:

a transmitter configured to transmit, in a subframe and in a downlink (DL) system bandwidth that includes an even number of M SB DL DL resource blocks (RBs) indexed in an ascending order, a physical DL control channel (PDCCH) or a physical DL shared channel (PDSCH) within a sub-band from a set of N SB DL DL sub-bands (SBs), wherein:

N SB DL =└M RB DL /6┘,

each SB in the set includes 6 RBs,

the 6 RBs of a SB in the set s are not included in any other SB in the set,

the SBs are indexed from 0 to N SB DB −1 in order of increasing RB index,

(M RB DL −└M RB DL /6┘·6)/2 RBs with smallest indexes and (M RB DL −└M RB DL /6┘·6)/2 RBs with largest indexes are not included in any SB in the set, and

└ ┘ is a floor function that rounds a number to an integer that is immediately smaller than the number.

2. The base station of claim 1 , wherein:

the transmitter is further configured to transmit first higher layer signaling configuring an index k 1 for a first sub-band for first repetitions of a PDCCH transmission, and

an index k 2 for a second sub-band for second repetitions of the PDCCH transmission is determined as k 2 =(k 1 +O SB DL )mod N SB DL where O SB DL is an offset and mod is a modulo operation.

3. The base station of claim 2 , wherein the transmitter is further configured to transmit a system information block that includes second higher layer signaling configuring a number of sub-bands for the PDCCH transmission and the offset.

4. The base station of claim 3 , wherein:

the first higher layer signaling configures the index of the first sub-band using ┌log 2 (N SB DL )┐ bits,

the second higher layer signaling configures the offset using ┌log 2 (N SB DL )┐ bits, and

┌ ┐ is a ceiling function that rounds a number to an integer that is immediately larger than the number and log 2 ( ) is a logarithm function with base 2.

5. The base station of claim 4 , wherein:

the PDCCH transmission conveys DL control information that schedules a PDSCH transmission and includes an information element of ┌log 2 (N SB DL )┐ bits indicating an index n 1 of a first sub-band for first repetitions of the PDSCH transmission, and

an index n 2 of a second sub-band for second repetitions of the PDSCH transmission is determined as n 2 =(n 1 +O SB DL )mod N SB DL .

6. The base station of claim 1 , wherein the transmitter is further configured to transmit:

a first system information block that includes third higher layer signaling configuring a number of coverage enhancement (CE) levels, and

a second system information block that includes fourth higher layer signaling configuring a physical uplink control channel (PUCCH) resource offset for each CE level.

7. A user equipment (UE) comprising:

a receiver configured to receive, in a subframe and in a downlink (DL) system bandwidth that includes an even number of M RB DL DL resource blocks (RBs) indexed in an ascending order, a physical DL control channel (PDCCH) or a physical DL shared channel (PDSCH) within a sub-band from a set of N SB DL DL sub-bands (SBs), wherein:

N SB DL =└M RB DL /6┘,

each SB in the set includes 6 RBs,

the 6 RBs of a SB in the set are not included in any other SB in the set,

the SBs are indexed from 0 to N SB DL −1 in order of increasing RB index,

(M RB DL −└M RB DL /6┘·6)/2 RBs with smallest indexes and (M RB DL −└M RB DL /6┘·6)/2 RBs with largest indexes are not included in any SB, and

└ ┘ is a floor function that rounds a number to an integer that is immediately smaller than the number.

8. The UE of claim 7 , wherein:

the receiver is further configured to receive first higher layer signaling configuring an index k 1 for a first sub-band for first repetitions of a PDCCH transmission, and

an index k 2 for a second sub-band for second repetitions of the PDCCH transmission is determined as k 2 =(k 1 +O SB DL )mod N SB DL where O SB DL is an offset and mod is a modulo operation.

9. The UE of claim 8 , wherein the receiver is further configured to receive a system information block that includes second higher layer signaling configuring a number of sub-bands for the PDCCH transmission and the offset.

10. The UE of claim 9 , wherein:

the first higher layer signaling configures the index of the first sub-band using ┌log 2 (N SB DL )┐ bits,

the second higher layer signaling configures the offset using ┌log 2 (N SB DL )┐ bits, and

┌ ┐ is a ceiling function that rounds a number to an integer that is immediately larger than the number and log 2 ( ) is a logarithm function with base 2.

11. The UE of claim 10 , wherein:

the PDCCH transmission conveys DL control information that schedules a PDSCH transmission and includes an information element of ┌log 2 (N SB DL )┐ bits indicating an index n 1 of a first sub-band for first repetitions of the PDSCH transmission, and

an index n 2 of a second sub-band for second repetitions of the PDSCH transmission is determined as n 2 =(n 1 +O SB DL )mod N SB DL .

12. The UE of claim 7 , wherein the receiver is further configured to receive:

a first system information block that includes third higher layer signaling configuring a number of coverage enhancement (CE) levels, and

a second system information block that includes fourth higher layer signaling configuring a physical uplink control channel (PUCCH) resource offset for each CE level.

13. A base station comprising:

a transmitter configured to transmit a number of repetitions for a physical downlink shared channel (PDSCH) conveying a data transport block (TB) wherein:

the number of repetitions is a multiple of four, and

the data TB is encoded using a first redundancy version in first four repetitions.

14. The base station of claim 13 , wherein:

the data TB is encoded using a third redundancy version in second four repetitions,

the data TB is encoded using a fourth redundancy version in third four repetitions, and

the data TB is encoded using a second redundancy version in fourth four repetitions.

15. The base station of claim 14 , wherein the PDSCH is scrambled with a first scrambling sequence in each of the first four repetitions, with a second scrambling sequence in each of the second four repetitions, with a third scrambling sequence in each of the third four repetitions, and with a fourth scrambling sequence in each of the fourth four repetitions.

16. The base station of claim 14 , wherein the transmitter is further configured to transmit, in a system information block, higher layer signaling for a hopping interval that indicates one of:

the first four and second four repetitions are in a first sub-band of a downlink system bandwidth and the third four and fourth four repetitions are in a second sub-band of the downlink system bandwidth,

the first four repetitions are in a first sub-band of a downlink system bandwidth, the second four repetitions are in a second sub-band of the downlink system bandwidth, the third four repetitions are in the first sub-band of the downlink system bandwidth, and the fourth four repetitions are in the second sub-band of the downlink system bandwidth, and

all repetitions are in a same sub-band of a downlink system bandwidth.

17. A user equipment (UE) comprising:

a receiver configured to receive a number of repetitions for a physical downlink shared channel (PDSCH) conveying a data transport block (TB) wherein:

the number of repetitions is a multiple of four, and

the data TB is encoded using a first redundancy version in first four repetitions.

18. A user equipment (UE) of claim 17 , wherein:

the data TB is encoded using a third redundancy version in second four repetitions,

the data TB is encoded using a fourth redundancy version in third four repetitions, and

the data TB is encoded using a second redundancy version in fourth four repetitions.

19. The UE of claim 18 , wherein the PDSCH is scrambled with a first scrambling sequence in each of the first four repetitions, with a second scrambling sequence in each of the second four repetitions, with a third scrambling sequence in each of the third four repetitions, and with a fourth scrambling sequence in each of the fourth four repetitions.

20. The UE of claim 18 , wherein the receiver is further configured to receive, in a system information block, higher layer signaling for a hopping interval that indicates one of:

that the first four and second four repetitions are in a first sub-band of a downlink system bandwidth and the third four and fourth four repetitions are in a second sub-band of the downlink system bandwidth,

the first four repetitions are in a first sub-band of a downlink system bandwidth, the second four repetitions are in a second sub-band of the downlink system bandwidth, the third four repetitions are in the first sub-band of the downlink system bandwidth and the fourth four repetitions are in the second sub-band of the downlink system bandwidth, and

all repetitions are in a same sub-band of a downlink system bandwidth.