An Overview of Peak-to-Average Power Ratio Reduction Techniques for OFDM Systems

This paper reviews several peak-to-average power ratio (PAR) reduction techniques and the related optimization problems. Chipping-based PAR reduction techniques are related to convex optimization problems and the global optimum solutions are relatively easy to find. Probabilistic techniques result in discrete optimization. Although finding its global optima is difficult, moderate suboptimal solutions can be achieved with low computational cost. Coding is promising because of its inherit error-correcting property. However, its extremely low coding rate in cases of large number of subcarriers prevents its application. Many criteria involve in the selection of a PAR reduction technique, e.g., PAR reduction capacity, power increase, bit error rate increase, complexity, and throughput. A main consideration is that the cost of extra complexity for PAR reduction is lower than the cost of power inefficiency. Low complexity PAR reduction techniques may find application in mobile communications