Separate Accumulation of UE Transmit Power Adjustment in Adaptive TDD Systems
A method of separate accumulation in closed-loop power control in adaptive TDD systems is proposed. A UE obtains configuration information from a base station in an adaptive TDD system. Each radio frame comprises a plurality of subframes, which are configured into two or more subframe sets. The UE receives a transmit power control (TPC) command in a downlink subframe. The UE determines a power control adjustment state for an uplink subframe i based on the TPC command. The power control adjustment state of subframe i is accumulated from a power control adjustment state of a previous uplink subframe j, where subframe i and subframe j belong to the same subframe set. In one embodiment, subframe j is the closest previous uplink subframe with respect to uplink subframe i.
1 . A method comprising:
obtaining configuration information by a user equipment (UE), wherein each radio frame comprises a plurality of subframes in an adaptive Time Division Duplexing (TDD) system, and wherein the subframes are configured as two or more subframe sets;
receiving a transmit power control (TPC) command in a downlink subframe; and
determining a power control adjustment state of an uplink subframe i based on the TPC command, wherein the power control adjustment state of subframe i is accumulated from a power control adjustment state of a previous uplink subframe j, and wherein subframe i and j belong to the same subframe set and i and j are positive integers.
2 . The method of claim 1 , wherein accumulation of the TPC command is enable by a higher layer.
3 . The method of claim 1 , wherein the TPC command is included in a physical downlink control channel (PDCCH) with downlink control information (DCI) format 0 .
4 . The method of claim 1 , wherein subframe j is the closest previous uplink subframe with respect to uplink subframe i.
5 . The method of claim 1 , wherein the TPC command is for Physical uplink shared channel (PUSCH) power control.
6 . The method of claim 1 , wherein the TPC command is for Physical uplink control channel (PUCCH) power control.
7 . The method of claim 6 , wherein the UE receives the TPC command in downlink subframe (i−k), and wherein the TPC command is taken into account only if subframe (i−k) belongs to the same subframe set.
8 . The method of claim 1 , wherein the subframes are configured into two subframe sets, wherein the first subframe set includes subframe # 2 , and wherein the second subframe set includes subframes # 3 - 4 and # 7 - 9 .
9 . A user equipment (UE) comprising:
a configuration module that obtains configuration information, wherein each radio frame comprises a plurality of subframes in an adaptive Time Division Duplexing (TDD) system, and wherein the subframes are configured as two or more subframe sets;
a receiver that receives a transmit power control (TPC) command in a downlink subframe; and
an uplink power adjustment module that determines a power control adjustment state of an uplink subframe i based on the TPC command, wherein the power control adjustment state of subframe i is accumulated from a power control adjustment state of a previous uplink subframe j, and wherein subframe i and j belong to the same subframe set and i and j are positive integers.
10 . The UE of claim 9 , wherein accumulation of the TPC command is enable by a higher layer.
11 . The UE of claim 9 , wherein the TPC command is included in a physical downlink control channel (PDCCH) with downlink control information (DCI) format 0 .
12 . The UE of claim 9 , wherein subframe j is the closest previous uplink subframe with respect to uplink subframe i.
13 . The UE of claim 9 , wherein the TPC command is for Physical uplink shared channel (PUSCH) power control.
14 . The UE of claim 9 , wherein the TPC command is for Physical uplink control channel (PUCCH) power control.
15 . The UE of claim 6 , wherein the UE receives the TPC command in downlink subframe (i−k), and wherein the TPC command is taken into account only if subframe (i−k) belongs to the same subframe set.
16 . The UE of claim 1 , wherein the subframes are configured into two subframe sets, wherein the first subframe set includes subframe # 2 , and wherein the second subframe set includes subframes # 3 - 4 and # 7 - 9 .