A Receiver-Assisted Joint Linearization Scheme for U6G Uplink Coverage Enhancement

With the growing demand from users, mobile communications are advancing towards <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\text{UGG}(6 \text{GHz}$</tex> upper band) and above. However, higher frequencies experience greater attenuation, limiting uplink coverage. Directly increasing terminal transmit power to improve uplink coverage, constrained by power amplifier (PA) nonlinearity, can lead to severe nonlinear distortion, causing out-of-band spectral leakage and degradation of in-band signal quality. This paper proposes a receiver-assisted joint linearization scheme to enhance terminal uplink coverage, which improves adjacent channel leakage ratio (ACLR) through model fit out-of-band nonlinear suppression technology digital predistortion algorithm at the transmitter and enhances error vector magnitude (EVM) using in-band digital post-correction algorithm at the receiver. Experimental results show a 2.28 dB increase in PA transmit power, a 9.13 dB improvement in ACLR for a DFT-s-OFDM-64QAM signal under severe nonlinear distortion in the U6G, and a reduction in EVM from 11.75% to <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$7.569 \%$</tex>.