Based On The SFLA Algorithm Of The MIMO-OFDM Adaptive Power Allocation

Under the premise of limited spectrum resources, it is an important problem to improve the utilization rate of spectrum and meanwhile overcome multipath fading in wireless communication technology. Therefore, it has a solution to solve the problem by combining the OFDM technology with MIMO technology.It can greatly improve the system spectrum utilization, also overcome frequency selective fading. So it is an important research direction by using MIMO-OFDM technology in the wireless communication field.This paper introduces a method to solve the MIMO-OFDM adaptive power problem by using leapfrog algorithm. The method is to distribute the transmission power to each sub-channel in MIMO-OFDM system according to the minimum requirements of the bit error rate. It can greatly reduce the system complexity and guarantee the system performance requirement. Firstly, to analyse the problem of MIMO system capacity, a comparative analysis between the average power allocation method and adaptive power allocation method is made, and find that the adaptive power technology can greatly enhance the capacity of MIMO system. Through the comparison the characteristics between MIMO system and MIMO-OFDM system, it points out that the adaptive power technology can also greatly enhance the capacity of MIMO-OFDM system. Then a analysis pointing to several typical power allocation algorithm helps to conclude the flooding algorithm, then to summarize the three criterions for adaptive power allocation, they are the maximum channel capacity criterion, the minimum bit error rate criterion and the minimum transmitted power criterion. By analysing of these three criterions for adaptive power allocation, it is found that the contradiction between demand optimization and real-time system universal exists. Therefore, the key problem to be solved is to guarantee the optimization system needs and meanwhile reduce the computational complexity. So the leapfrog algorithm is used to conclude a improved algorithm for system power bit allocation,which provides the efficient computation and search ability.Through the simulation test and analysis, it is proved that the improved algorithm can reduce the computational complexity and meanwhile guarantee the system performance.