Configuration of uplink and downlink grant search spaces in an OFDM-based mobile communication system

摘要

The invention relates to methods for detecting at least one of a downlink grant and an uplink grant within a sub-frame of an OFDM-based mobile communication system. The invention provides a reception apparatus (e.g. a relay node or a mobile terminal) that are adapted to perform these methods. The invention defines the uplink grant search space to form a subset of the downlink grant search space. In other words, in the frequency domain, the uplink grant search space is defined on a subset of the resource block pairs that form the downlink search space. This configuration allows downlink data to be mapped to the remaining resources outside the uplink grants search space and the resources used for a downlink grant. Furthermore, the downlink grants comprise an indication of whether the uplink grant search space in the sub-frame comprises (user) data or not.

主权项

1. A method for detecting at least one of a downlink grant and an uplink grant within a sub-frame of a OFDM-based mobile communication system, the method comprising the following steps performed by a reception apparatus:
receiving a sub-frame from a base station, wherein the sub-frame is logically divided into physical resource block pairs, and a respective resource block pair consisting of a resource block within a first slot of the sub-frame and a resource block within a second slot of the sub-frame, performing a blind detection to detect a downlink grant within a downlink grant search space of the sub-frame, wherein the downlink grant search space consists of plural physical resource blocks of resource block pairs within the first slot of the sub-frame, performing a blind detection to detect an uplink grant within an uplink grant search space of the sub-frame, wherein the uplink grant search space consists of plural physical resource blocks within the second slot of the sub-frame, and wherein the physical resource blocks within the second slot is located within a subset of the physical resource block pairs, on which the physical resource blocks within the first slot form the downlink grant search space, demodulating and decoding downlink data according to the detected downlink grant, and modulating, coding, and transmitting transmittal data according to the detected uplink grant.