Transmit power control signaling for communication systems using carrier aggregation

摘要

Transmission power control and signaling from a base station to a group of terminals in a system such as LTE supporting carrier aggregation. The transmission power control message has a plurality of transmission control fields of which a multiple is assigned to each terminal. A transmission control field carries a transmission power command for the respective uplink component carrier and the respective mobile terminal. The transmission power control message is mapped to a control signaling region of a downlink component carrier and transmitted within a subframe.

主权项

1. A method for transmitting transmit power control commands from a base station to a group of mobile terminals in a OFDM based mobile communication system using component carrier aggregation of plural uplink component carriers, the method comprising following steps performed by the base station:
generating a transmit power control message having a plurality of transmit power control fields, wherein multiple of the transmit power control fields of the transmit power control message are respectively assigned to different mobile terminals, wherein the multiple transmit power control fields assigned to each mobile terminal signal transmit power commands for the uplink component carriers aggregated by the respective mobile terminal, mapping the transmit power control message to a control signaling region of a downlink component carrier, transmitting within a sub-frame the transmit power control message comprised in the control signaling region of the downlink component carrier to the mobile terminals, generating a Cyclic Redundancy Check (CRC) code for the transmit power control fields of the transmit power control message, masking the CRC code with one of plural temporary identifiers common to group of mobile terminals defined for transmit power control to obtain a first masked CRC code, including the first masked CRC code to a CRC field of the transmit power control message prior to its mapping to the control signaling region of the downlink component carrier, and configuring different dedicated search spaces of the mobile terminals by RRC signalling, wherein a search space of a mobile terminal defines a part of the control signalling region within each sub-frame in which the mobile terminal is to perform blind detection of the control information, including the transmit power control messages, wherein the base station generates and transmits plural transmit power control messages for different groups of mobile terminals within the sub-frame, each of the transmit power control messages including a second masked CRC masked with a different one of the plural temporary identifiers common to group of mobile terminals defined for transmit power control, wherein the step of mapping includes mapping the each transmit power control message to a part of the control signalling region within the sub-frame comprised in the search spaces of the mobile terminals assigned transmit power control fields within the respective transmit power control message, wherein one of the multiple transmit power control fields assigned to one mobile terminal within the transmit power control message is signalling a transmit power control command for all uplink component carriers configured for the mobile terminal, and at least one other transmit power control field of the transmit power control message is signalling a transmit power control command for a subset of the uplink component carriers configured for the mobile terminal.