POWER-LIMIT REPORTING IN A COMMUNICATION SYSTEM USING CARRIER AGGREGATION

摘要

The invention relates to methods for informing an eNodeB on the transmit power status of a user equipment in a mobile communication system using component carrier (CC) aggregation. Furthermore, the invention is also related to the implementation of these methods by hardware and their implementation in software. The invention proposes procedures that allow the eNodeB to recognize the power usage status of a UE in a communication system using carrier aggregation. The UE indicates to the eNodeB, when the UE is close to using its total maximum UE transmit power or when it has exceeded same. This is achieved by the UE including indicator(s) and/or new MAC CEs to one or more protocol data units transmitted on respective component carriers within a single sub-frame that is providing the eNodeB with power status information. The MAC CEs may report a per-UE power headroom. Alternatively, the MAC CEs may report per-CC power headrooms and/or power reductions applied to the respective uplink CCs.

主权项

1. An integrated circuit comprising:
circuitry which, in operation, generates a power status report to inform an eNodeB of a transmit power status of a user equipment (UE) in a wireless communication system using component carrier aggregation, in which two or more component carriers (CCs) are aggregated, wherein the power status report includes:
(i) a CC specific maximum transmission power, PCMAX,c, for each configured and activated uplink CC, wherein PCMAX,c is set within bounds:
PCMAX_L,c<=PCMAX,c<=PCMAX_H,c where PCMAX_L,c is a lower bound and PCMAX_H,c is a higher bound of a CC specific maximum transmission power, and(ii) a power headroom report indicative of a difference between the CC specific maximum transmission power, PCMAX,c, and an estimated UE transmit power, per each configured and activated uplink CC, wherein the CC specific maximum transmission power, PCMAX,c, for each configured and activated CC is included in the power status report when a resource is assigned for the configured and activated uplink CC for the UE, and at least one output node coupled to the circuitry which, in operation, outputs the power status report for transmission to the eNodeB.