Second-order Passive Intermodulation Distortion Modeling Using a Quadratic Volterra Filter for Wireless Relay Systems

Passive intermodulation distortion (PIMD) is a phenomenon in which two or more transmission signal frequencies interact with each other due to non-linearity in passive elements of a wireless communication system, and undesired signals are generated. Such intermodulation distortion increases the noise level in the receive frequency band of the wireless communication system, thereby degrading the performance of the receiver. In this paper, a PIMD modeling is investigated with a modified quadratic Volterra filter, which can be applied to reduce a passive intermodulation distortion level to enhance the uplink receive performance. The performance of the proposed approach is evaluated by employing it to the data sampled at a relay for the long term evolution (LTE) system.