Effects of Nonlinear Amplifiers and Narrowband Interference in MIMO-OFDM with Application to 802.11n WLAN

One of the disadvantages that are associated with Orthogonal Frequency Division Multiplexing (OFDM) is high peak to average power ratio (PAPR). In most cases, this high peak signal often forces practical amplifiers to operate in the nonlinear region and causes additional degradation to the system's performance. Since the frequency bandwidth is a scarce resource, it is inevitable that a wireless communication system would have to operate in an environment that is prone to interference. Therefore, it is important to understand how an OFDM system performs in such situations. In this paper, we analyze the joint effect of nonlinear distortion produced by high power amplifiers (HPAs) and narrowband interference (NBI) on the performance of a Multiple Input Multiple Output (MIMO) OFDM system in Rayleigh fading channels. We then extend the analytical model to be in compliance with the IEEE 802.11n standard for the purpose of simulation. The theoretical results are verified with the simulation.