Resource distribution strategy for OFDM relay system

Abstract

The invention aims at providing a dynamic resource distribution strategy capable of improving the system capacity in an OFDM system. A dynamic resource distribution algorithm research proposes an optimal subcarrier matching algorithm and an optimal power distribution algorithm on the basis of a model of an OFDM double-hop regeneration relay system under a diversity mode. In the optimal subcarrier matching algorithm, according to the size of a channel gain, all subcarriers in a plurality of hops of links are ranked and matched so as to maximize an equivalent total signal-to-noise ratio of the system. In the optimal power distribution algorithm, transmission power of each subcarrier pair is distributed through a water injection power distribution algorithm and equality of channel capacity of each hop of link in the subcarrier pairs is used as a criterion to adjust the signal transmission power of each hop of link and thus the capacity of the system is maximized.

Description

technical field [0001] The invention relates to a resource allocation strategy of an OFDM two-hop regenerative relay system in a diversity mode. Background technique [0002] Although Orthogonal Frequency Division Multiplexing (OFDM) technology has improved the spectrum utilization rate, the traditional single-hop system between the base station and the user is still difficult to meet the user throughput requirements, especially the needs of edge cell users . The application of relay technology can improve the system capacity and base station coverage area and other performances. At present, the OFDM relay (OFDM-Relay) system is divided into diversity mode and non-diversity mode according to whether the user terminal receives the signal directly transmitted by the transmitter. In the diversity mode, when the channel state of the relay link is poor, the user directly receives the signal transmitted by the base station. The performance of the OFDM-Relay system is better, but...

AI Technical Summary

Problems solved by technology

In order to solve the problem that the subcarriers appearing in the fixed subcarrier matching algorithm have too much channel gain difference between each hop link, the present invention proposes an optimal subcarrier matching algorithm, that is, for all subcarriers in the S-R link and the R-D link Sort according to the order of channel gain from large to small, and sort all subcarriers of the S-D link according to the order of channel gain from small to large, match the first subcarrier in the three-hop link after sorting, and sort The second subcarrier in the three-hop link is matched, and so on until all subcarriers are matched

Images