Adaptive Carrier Allocation Strategy Based On Orthogonal Frequency Division Multiplexing

With the development of wireless communication, the next-generation communication technologies are required to support higher transmission rate and the higher rate of mobile users. They are also required to gain higher spectrum efficiency and have better ability against multi-path interference. Orthogonal frequency division multiplexing (OFDM) as the representative of the multi-carrier modulation technique proved to be one of the most promising. It is the development trend that OFDM will be used in the field of broadband wireless access. It will become a key technology for future mobile communication systems.Based on the analysis of the technological principles, advantages and disadvantages of OFDM, this paper focuses on the technical characteristics and network performance of FLASH-OFDM and Flexband of improved technology. It also does a research of the user capacity of downlink in the FH-OFDMA cellular system. And the problem is analyzed that the data transmission speed of cell edge in Flexband cellular system should be improved. To solve the problem of Flexband system, we propose an adaptive carrier allocation strategy, which can adaptively adjust the number of practicable subcarrier of the cell edge. The simulation results show that the method we presented can improve the sum-of-rates capacity of the cell edge and increase the number of users supported.