A Crest Factor Reduction Method in Digital Predistortion for Improvement of Power Efficiency

Digital predistortion, which is used to compensate for the nonlinearity introduced by power amplifiers, plays an important role in the linearization techniques. Saturation distortions caused by high peak-to-average ratio of input signal, however, cannot be compensated through digital predistortion. As a result, power amplifiers have to operate with back-off and result in relatively low efficiency. In this paper, a new pulse cancellation method of crest factor reduction technique is proposed which can considerably increase power efficiency without power back-off by reducing the high peak-to-average ratio. Simulation results show that using PCM method of CFR prior to DPD can achieve not only a desirable linearization performance, but also a significant increase in power level.