UPLINK ENHANCEMENTS FOR EFFICIENT OPERATION IN SMALL CELL ENVIRONMENTS
In embodiments, apparatuses, methods, and storage media may be described for processes that may be performed in a network with decoupled uplink (UL)-downlink (DL) association. Specifically, if a user equipment (UE) is configured to receive DL transmissions from a macro cell, and transmit UL transmissions to a small cell, hybrid automatic repeat request (HARQ) or power control (PC) may be described.
1 . A method comprising:
receiving, by a user equipment (UE), a downlink transmission from a first cell;
transmitting, by the UE responsive to the downlink transmission, a physical uplink shared channel (PUSCH) transmission;
receiving, by the UE responsive to the PUSCH transmission, an uplink (UL) grant indicating a re-transmission of the PUSCH transmission; and
transmitting, by the UE responsive to the UL grant, the PUSCH transmission.
2 . The method of claim 1 , wherein the UL grant is a UL grant from the first cell.
3 . The method of claim 2 , wherein the UL grant is received on a physical downlink control channel (PDCCH) or an enhanced PDCCH (ePDCCH) of the first cell.
4 . The method of claim 1 , wherein the UL grant is a UL grant from a second cell.
5 . The method of claim 4 , wherein the UL grant is received on a physical downlink control channel (PDCCH) or an enhanced PDCCH (ePDCCH) of the second cell.
6 . The method of claim 1 , wherein the first cell or the second cell are configured to not transmit an indicator to the UE on a physical hybrid automatic repeat request indicator channel (PHICH) of the first cell or a PHICH of the second cell.
7 . An apparatus comprising:
a communication module to:
receive a physical downlink control channel (PDCCH) or enhanced PDCCH (ePDCCH) transmission from a first cell; and
transmit, responsive to the PDCCH or ePDCCH transmission, a physical uplink shared channel (PUSCH) transmission; and
a re-transmission module to:
facilitate, in response to identification of an uplink (UL) grant received in a downlink (DL) transmission and independent of a physical hybrid automatic repeat request indicator channel (PHICH) transmission from the first cell or a second cell, a re-transmission of a previously-transmitted PUSCH transmission.
8 . The apparatus of claim 7 , wherein the UL grant is a UL grant from the first cell.
9 . The apparatus of claim 8 , wherein the communication module is further to receive the UL grant in the PDCCH or ePDCCH transmission of the first cell.
10 . The apparatus of claim 7 , wherein the UL grant is a UL grant from the second cell.
11 . The apparatus of claim 10 , wherein the communication module is further to receive the UL grant in a physical downlink control channel (PDCCH) or an enhanced PDCCH (ePDCCH) of the second cell.
12 . The apparatus of claim 7 , wherein the communication module is further to:
receive an indication in a radio resource control (RRC) signal from the first cell; and
receive, based at least in part on the indication, a PHICH signal from the second cell.
13 . The apparatus of claim 12 , wherein the indication, includes an indication of a physical cell identifier (PCI), a number of orthogonal frequency division multiplexing (OFDM) symbols for a PDCCH transmission, a starting symbol for a physical downlink shared channel (PDSCH) transmission, a duration of a PHICH transmission, or a configuration parametera of a physical broadcast channel (PBCH) transmission that may include one or more antenna port (AP) configuration.
14 . The apparatus of claim 7 , wherein the communication module is a baseband module and the apparatus further comprises a multi-mode transceiver chip that includes the baseband module, the re-transmission module, and a power management unit to control power provided to the baseband and re-transmission modules.
15 . A method comprising:
identifying, by a user equipment (UE) configured to transmit uplink signals using one or more power control (PC) processes, one or more closed loop (CL) PC processes for physical uplink shared channel (PUSCH) transmissions of the UE;
identifying, by the UE, a second CL PC process for a first physical uplink control channel (PUCCH) transmission from the UE; and
identifying, by the UE, a third CL PC process for a second PUCCH transmission from the UE that is concurrent with the second CL PC process.
16 . The method of claim 15 , wherein the second or third CL PC process is based on a PUCCH format of the first or second PUCCH transmissions.
17 . The method of claim 15 , further comprising identifying, by the UE, a pathloss reference based at least in part on a first cell.
18 . The method of claim 15 , further comprising identifying, by the UE, a first cell or a second cell as a pathloss reference based at least in part on a radio resource control (RRC) signal received by the UE.
19 . The method of claim 18 , further comprising receiving, by the UE, a first value for open loop (OL) PC parameters, the first value associated with the use of the first cell as a pathloss reference; and
receiving, by the UE, a second value for OL PC parameters, the second value associated with the use of the first cell as a pathloss reference;
wherein the OL PC parameters include P O — PUCCH , P O — NOMINAL — PUCCH , or P O — UE — PUCCH .
20 . The method of claim 18 , further comprising identifying, by the UE in a transmission received from the eNB of the first cell, a transmit power control (TPC) command; and
changing, by the UE, a transmit power of the first CL PC, second CL PC, or third CL PC based at least in part on the received TPC command.
21 . One or more non-transitory computer readable media comprising instructions configured to cause a user equipment (UE) configured to receive downlink transmissions from a first cell of a wireless network and transmit uplink transmissions, upon execution of the instructions by the UE, to:
identify a closed loop (CL) power control (PC) process for a physical uplink control channel (PUCCH) of the UE;
identify, based on a downlink (DL) signal from the first cell, a non-cumulative transmit power control (TPC) command for the CL PC process; and
adjust a transmission power value of a PUCCH transmission based at least in part on a value of the non-cumulative TPC command.
22 . The one or more non-transitory computer readable media of claim 21 , wherein the instructions further comprise instructions to adjust the transmission power value of the PUCCH transmission based at least in part on pathloss reference of the PUCCH transmission.
23 . The one or more non-transitory computer readable media of claim 21 , wherein the PUCCH CL PC process is maintained at a second cell and the PUCCH transmission is a PUCCH transmission targeted to the first cell.
24 . The one or more non-transitory computer readable media of claim 21 , wherein the PUCCH CL PC process is maintained at the first cell and the PUCCH transmission is a PUCCH transmission targeted to a second cell.
25 . The one or more non-transitory computer readable media of claim 21 , wherein the PUCCH transmission is configured according to a delay-sensitive third generation partnership project (3GPP) PUCCH format.