Iterative canceller of adjacent channel interference induced by nonlinearity of power amplifier in millimeter wave systems

This paper proposes an iterative cancellation scheme for adjacent channel interference (ACI) caused by nonlinear transmit power amplifier (PA) in millimeter wave (mmW) systems with the assistance of a nonlinear estimator and channel decoder´s feedback. In this method, nonlinear distortion included in the transmit signal is estimated by polynomial regression analysis using not only the pilot signal but also the regenerated modulated signal in the receiver to enhance estimation accuracy in the higher signal level regions. Frequency selective fading is also compensated for. We have demonstrated that ACI cancellation with proposed nonlinearity estimation is capable of improving bit error rate (BER) performances in the presence of ACI, and have shown effectiveness and usefulness of the proposed scheme when IEEE 802.11ad using spectrum bands located adjacently in the same place.