Resource distribution and power distribution method for cellular multi-cell orthogonal frequency division multiple access (OFDMA) system

Abstract

The invention discloses a resource distribution and power distribution method for a cellular multi-cell orthogonal frequency division multiple access (OFDMA) system. The resource distribution and power distribution method is characterized by comprising the following steps of: initializing a base station, establishing a bandwidth distribution scheme of each cell, determining a sub-carrier distribution scheme of users; distributing sub-carrier power to each cell; calculating and transmitting an interference cost factor of the neighboring cell; updating the interference cost factor transmitted to the cell by the neighboring cell; executing the next period of bandwidth and power distribution; and circulating the steps. In the distribution method, each base station can determine the transmitting power independently only with the limited cooperation existed among the base stations and through the share of the interference cost factor among the base stations, so that the interference level among the cells can be effectively controlled and the performance of the system can be optimized. Furthermore, a large burden is not brought into the information transfer among the base stations, so the distribution method has high practicability.

Description

technical field [0001] The invention belongs to the technical field of communications, and relates to a power allocation method for a cellular multi-cell system, in particular to a power allocation method for a cellular multi-cell system based on MIMO-OFDMA technology that has a minimum transmission rate limit for users. Background technique [0002] Multi-antenna OFDMA technology is the basic physical layer technology of the third-generation mobile communication including LTE and Wimax. By adopting larger bandwidth and higher spectral efficiency, the peak rate it can provide is much higher than that of the current 3G cellular mobile communication system. OFDMA technology enables the base station to schedule the user's frequency domain resources, transmission power, modulation mode, etc. on the subcarriers of the frequency domain. Compared with the 3G system, it is more flexible and can achieve no mutual interference between users in the cell. In order to make more effective...

AI Technical Summary

Problems solved by technology

In order to make more effective use of carrier frequency resources, it is necessary to implement power allocation on the subcarriers allocated to each user, but the current power allocation algorithms are all focused on the allocation of resources and power between users in a single cell, and few Consider the user's QoS requirements

In addition, because the OFDMA system adopts frequency reuse in adjacent cells, the interference of OFDMA to users between cells cannot be ignored, especially at the edge of the cell, it will greatly reduce the spectral efficiency of the user, and even the system will give the cell Edge users are allocated more frequency domain resources, and the power cannot meet the user's transmission rate requirements, which reduces the overall spectrum efficiency in the cell

If it is necessary to reduce the interference of user signals between cells and realize the optimal power and frequency domain resource allocation of multi-user joints in adjacent cells, a control device capable of centralized control of multiple base stations is required, and multiple adjacent base stations are required to Feedback the mutual interference information to the central controller for centralized processing and distribution, but this is contradictory to the flat network structure of LTE and Wimax in the future

Moreover, due to the large number of carriers, the joint optimization problem of power allocation and carrier allocation to ensure the transmission rate of users will become extremely complicated

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