The effect of cellular portable unit amplifier non-linearity on the performance of the multi-carrier CDMA system

A number of multi-carrier CDMA systems have been introduced as alternatives for the conventional single carrier CDMA system. Multi-carrier modulation offers many advantages over single carrier modulation in fading channels, impulsive noise and for high data rate applications. With the availability of fast DSP technology multi-carrier modulation is feasible. A major problem in multi-carrier systems is the inter-modulation distortion due to the non-linearity of the power amplifier stage. Since the multi-carrier signal has a large amplitude variation it is subject to AM/AM and AM/PM distortion due to power amplifiers. This distortion adds to the co-channel interference and causes a significant degradation to the system performance. This paper studies the performance of the multi-carrier CDMA system in an AWGN channel without fading but with amplifier non-linearity.