Low PMEPR OFDM radar waveform design using the iterative least squares algorithm

摘要

This letter considers waveform design of orthogonal frequency divisionmultiplexing (OFDM) signal for radar applications, and aims at mitigating theenvelope fluctuation in OFDM. A novel method is proposed to reduce thepeak-to-mean envelope power ratio (PMEPR), which is commonly used to evaluatethe fluctuation. The proposed method is based on the tone reservation approach,in which some bits or subcarriers of OFDM are allocated for decreasing PMEPR.We introduce the coefficient of variation of envelopes (CVE) as the costfunction for waveform optimization, and develop an iterative least squaresalgorithm. Minimizing CVE leads to distinct PMEPR reduction, and it isguaranteed that the cost function monotonically decreases by applying theiterative algorithm. Simulations demonstrate that the envelope is significantlysmoothed by the proposed method.