الفهرس 
chapter 1Only 14 pages are availabe for public view
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Abstract
the key challenge faced by future wireless communication systems is to provide high data rate wireless access at high quality of service (QoS). Combined with the facts that, spectrum is a scarce resource, and propagation conditions are hostile due to fading caused by destructive addition of multipath components and interference from other users.
Orthogonal frequency division multiplexing (OFDM) is a multi-carrier modulation technique for high data rate wireless communications due to its robustness to frequency selective fading, high spectral efficiency and low computational complexity. OFDM can be used in conjunction with multiple input multiple output (MIMO) technique to increase the diversity gain and/or the system capacity by exploiting spatial domain.
However, the main drawback of MIMO OFDM systems is high peak to average power ratio (PAPR) . because of its sensitivity to the nonlinear distortions introduced by nonlinear devices, such as digital to analog converters (DAC) and high power amplifiers (HPA). These distortions may severely impair system performance due to induced spectral regrowth and detection efficiency degradation.