Transmission of control channel and data channels for coverage enhancements
Methods and apparatus are provided for a base station to transmit and for a User Equipment (UE) to receive repetitions of an enhanced physical downlink control channel (EPDCCH). Time and frequency resources for EPDCCH repetitions are defined together with restrictions in time resources to provide UE power savings. Time and frequency resources are also defined for repetitions of a physical downlink shared channel (PDSCH) transmission and for repetitions of a physical uplink shared channel (PUSCH) transmission. Methods and apparatus are also provided for the UE to transmit and for the base station to receive acknowledgement information in repetitions of a physical uplink shared channel (PUCCH).
1. A method comprising:
configuring, by a base station to a user equipment using higher layer signaling, a first number of consecutive subframes (SFs) and a second number of consecutive SFs that is included in the first number of consecutive SFs starting from a first SF of the first number of consecutive SFs;
transmitting, by the base station to the UE, a physical downlink control channel over one or more SFs only from the second number of SFs; and
mapping, by the base station, a first repetition for a transmission of a physical downlink control channel in a SF with index n s , wherein the SF is located in a frame that includes ten SFs and has system frame number (SFN) Z, and is determined as (10Z+n s )mod P=0, where P is a number of SFs.
2. The method of claim 1 , wherein P=N·R max , N is an integer, and R max is a maximum number of repetitions for the physical downlink control channel.
3. The method of claim 2 , wherein the first number of consecutive SFs is P and the second number of consecutive SFs is R max .
4. The method of claim 3 , wherein the P SFs or the R max SFs include SFs where the base station does not transmit the physical downlink control channel and the SFs are counted in the determination of P and R max .
5. The method of claim 1 , wherein the base station transmits more than one repetitions of the physical downlink control channel transmission using aggregation levels of control channel elements that always include more than two control channel elements.
6. A method comprising:
determining a number of repetition for a physical uplink control channel (PUCCH) or for a physical uplink shared channel (PUSHC) over a number of sub-frames (SFs); and
transmitting the repetitions of the PUCCH or of the PUSCH over the number of SFs, wherein the repetitions hop onto two different sets of frequency resource blocks and remain in the same set of frequency resource blocks over a number of consecutive SFs that is larger than one.
7. The method of claim 6 , wherein the number of consecutive SFs is four.
8. A base station comprising:
a controller configured to configure a first number of consecutive sub-frames (SFs) and a second number of consecutive SFs that is included in the first number of consecutive SFs start from the first SF of the first number of consecutive SFs;
a transmitter configured to transmit a physical downlink control channel over one or more SFs only from the second number of SFs; and
a mapper configured to map a first repetition for a transmission of a physical downlink control channel in a SF with index n s , wherein the SF is located in a frame that includes ten SFs and has system frame number (SFN) Z, and is determined as (10Z+n s )mod P=0, where P is a number of SFs.
9. The base station of claim 8 , wherein P=N·R max , N is an integer, and R max is a maximum number of repetitions for the physical downlink control channel.
10. The base station of claim 9 , wherein the first number of consecutive SFs is P and the second number of consecutive SFs is R max .
11. The base station of claim 10 , wherein the P SFs include SFs where the base station does not transmit the physical downlink control channel and the SFs are counted in the determination of P and R max .
12. A User Equipment (UE) comprising:
a controller configured to determine a first number of consecutive subframes (SFs) and a second number of consecutive SFs that is included in the first number of consecutive SFs starting from the first SF of the first number of consecutive SFs;
a receiver configured to receive a physical downlink control channel over one or more SFs only from the second number of SFs; and
a mapper configured to map a first repetition for a reception of a physical downlink control channel in a SF with index n s , wherein the SF is located in a frame that includes ten SFs and has system frame number (SFN) Z, and is determined as (10Z+n s )mod P=0, where P is a number of SFs.
13. The UE of claim 12 , wherein P=N·R max , N is an integer, and R max is a maximum number of repetitions for the physical downlink control channel.
14. The UE of claim 13 ,
wherein the first number of consecutive SFs is P and the second number of consecutive SFs is R max .
15. The UE of claim 14 , wherein the P SFs or the R max SFs include SFs where the UE does not receive the physical downlink control channel and the SFs are counted in the determination of P and R max .
16. A base station comprising:
a controller for determining a number of repetitions for a physical uplink control channel (PUCCH) or for a physical uplink shared channel (PUSCH) over a number of subframes (SFs); and
a receiver configured to receive the repetitions of the PUCCH or of the PUSCH over the number of subframes (SFs) wherein the repetitions hop onto two different sets of frequency resource blocks and remain in the same set of frequency resource blocks over a number of consecutive SFs that is larger than one.
17. The apparatus of claim 16 , wherein the number of consecutive SFs is four.