Resource distribution method in orthogonal frequency division multiple access (OFDMA) relay system

Abstract

The invention discloses a resource distribution method in an orthogonal frequency division multiple access (OFDMA) relay system. The resource distribution method comprises the following processing steps: (1) calculating to obtain the number of sub-carriers which can be distributed by each user and the number of the sub-carriers which are not distributed initially; (2) distributing the sub-carriers and corresponding relays to each user; distributing the number of the sub-carriers which can be distributed to each user first and then distributing the number of the sub-carriers which are not distributed initially; and (3) obtaining a power value distributed to each sub-carrier by utilizing a Lagrange multiplier method according to the condition that the sub-carriers distributed to each forward pass user in the step (2), the sub-carriers which are transmitted by each relay and the total transmission power are checked. By the method, the requirements of each user on the rate are met; a near-far effect in wireless communication is avoided; the quick change in a wireless communication environment can be adapted very well; the calculation complexity is reduced; and meanwhile, the system resource utilization rate is improved effectively.

Description

technical field [0001] The present invention relates to a resource allocation method of a communication system, in particular to a resource allocation method of an OFDMA (Orthogonal Frequency Division Multiple Access, Orthogonal Frequency Division Multiple Access) relay system. Background technique [0002] OFDMA is a wireless access method based on OFDM (Orthogonal Frequency Division Multiplex, Orthogonal Frequency Division Multiplex) modulation. It has the characteristics of high transmission rate, flexible resource allocation, and can support multiple users at the same time. The key technology of the first-generation broadband wireless access method has been applied in standards such as IEEE802.16d / e. The OFDMA system divides the transmission bandwidth into a series of orthogonal non-overlapping subcarrier sets, and allocates different subcarrier sets to different users to realize multiple access. [0003] The resource allocation problem of an OFDMA system with relays is...

AI Technical Summary

Problems solved by technology

The traditional solution is to allocate fixed subcarriers and relays for each user, and then perform power allocation, bit allocation and adaptive modulation according to the allocation scheme of subcarriers and relays. Since the subcarriers and relays allocated by this solution are Fixed, so it cannot adapt well to changes in the wireless communication environment, such as the influence of obstacles, changes in ambient temperature, etc., resulting in poor communication for some users and low utilization of system resources

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