Joint Mitigation of IQ Imbalance and Power Amplifier Impairments by Real Valued Time Delay Neural Networks

Abstract

This paper represents a neural network based joint mitigation of the IQ imbalance and power amplifier nonlinearities that cause degradation in the transmit signal quality of the wireless communication systems. A Real Valued Time Delay Neural Network architecture for this purpose has been verified on a hardware including cascaded NXP-MD8IC925 and NXPBLF8G10LS power amplifier components performing a total of 46dB gain. The test setup has been controlled over MATLAB in order to have a closed loop adaptive digital predistortion. The test results showed approximately 24dB, 19dB and 14dB performance improvements for the in-band, first and second adjacent channels, respectively.