Optimization Method of Power Allocation in OFDM Using Least Squares Method

Abstract

In this paper  glance into the performance of such cooperative OFDMA systems beneath realistic conditions is to  propose a transceiver structure to scale back the interference between transmission subcarriers and receiving subcarriers. Its performance in terms of signal to interference and noise ratio (SINR) is evaluated by each analysis and simulation and is incorporated into a recently planned cooperation strategy for OFDMA systems to look at its performance below the realistic structure. we present an improved DFT-based channel estimation technique. the standard separate Fourier transforms (DFT)-based approach can cause energy outflow in multipath channel with non-sample-spaced time delays. The improved technique uses symmetrical property to increase the LS estimate in frequency domain, and calculates the ever-changing rate of the escape energy, and selects helpful methods by the ever-changing rate. the computer simulation results show the improved technique will scale back the outflow energy with efficiency, and therefore the performance of the improved channel estimation technique is best than the LS and standard DFT formula.