The performance of orthogonal frequency multiplexing (OFDM) communication systems is affected by the peak to average power ratio (PAPR). The research work uses a hybrid transform for reducing this PAPR value. In recent years, OFDM is more prevalent in the research field, particularly in wireless communication. OFDM system is found to have a high PAPR value. This high PAPR leads to nonlinear distortions that result in low power efficiency. Hence there is a need to minimize PAPR. Hadamard transform is a commonly used technique for the reduction of PAPR. However, greater efficiency can be carried out using a hybrid way to reducing the PAPR of the signals applying OFDM. Modified Discrete Cosine Transform (MDCT) combined with nonlinear companding technique, is suggested to minimize PAPR, described as a hybrid transform. It is shown that the hybrid transform achieves a better lessening of PAPR and minimized Bit Error Rate (BER) in the OFDM communication system when compared with the basic OFDM, Hadamard transforms, and Companding technique.

正交频分复用（OFDM）通信系统的性能受峰均功率比（PAPR）的影响。研究工作使用混合变换来降低此PAPR值。近年来，OFDM在研究领域中更加普遍，特别是在无线通信中。发现OFDM系统具有较高的PAPR值。高PAPR会导致非线性失真，从而导致低电源效率。因此，需要使PAPR最小化。Hadamard变换是降低PAPR的常用技术。但是，可以使用混合方式降低应用OFDM的信号的PAPR，以实现更高的效率。建议将改进的离散余弦变换（MDCT）与非线性压扩技术相结合，以使PAPR最小化，称为混合变换。