Communication device and method of crest factor reduction using amplitude compression

摘要

A method of crest factor reduction using amplitude compression for multi carrier signals. Major elements of the inter-modulation distortion caused by amplitude suppression are removed to be outside of the desired signal band, and the peak amplitude is compressed, thus producing a signal with lower peak to average ratio for a required maximum error vector magnitude.

主权项

1. A method of crest factor reduction (CFR) using amplitude compression, executable by a communication device, the method comprising:
receiving a complex input signal x(t) at a first sampling rate Rs; up-sampling the complex input signal x(t) to a second sampling rate M·Rs that is larger than an instantaneous bandwidth of the complex input signal x(t), to generate an up-sampled complex signal y(t); computing an amplitude signal a(t) representing an amplitude of the up-sampled signal y(t) and sending the amplitude signal a(t) to an amplitude compressor of the communication device to extract the compressed gain g1(t); multiplying the gain g1(t) with a correction gain g2(t) to obtain a final gain signal g(t); performing amplitude compression of the up-sampled complex signal y(t) by multiplying the gain signal g(t) with the up-sampled complex signal y(t) to produce the amplitude compressed signal z(t); performing signal filtering by the filter of the communication device on the amplitude compressed signal z(t) to generate a post-CFR signal u(t), wherein the post-CFR signal u(t) is at a higher sampling rate and with a lower peak to average (PAR) ratio than the complex input signal x(t).