Advanced Approach for TX Impairments Compensation Based on Signal Statistical Analysis at the RX Side

The paper proposes a new method for compensation of the transmitter (TX) power amplifier (PA) nonlinearity and I/Q imbalance impairments at the receiver (RX) side for single carrier (SC) communication systems. This method is based on the straightforward statistical analysis of the received data symbols for estimating distortion effects. The updated estimates of the constellation point position are then used to demodulate the received signals by calculating the LLR (Log Likelihood Ratio) metrics for each received bit in a soft demodulation/decoding algorithm. In comparison with well-known TX pre-distortion schemes and TX impairment compensation at the RX side, the proposed self-learning algorithm demonstrates much less complexity and therefore may be recommended for application to Internet-of-Things (IoT) communication networks in future 5G systems. The efficiency of the developed algorithm was tested at the link level simulator of the Wi-Fi communication system based on the IEEE 802.11ad standard.