Orthogonal frequency-division multiplexing (OFDM) time-domain signals exhibit high peak-to-average (power) ratio (PAR), which requires linear radio-frequency chains to avoid an increase in error-vector magnitude (EVM) and out-of-band (OOB) emissions. In this paper, we propose a novel joint PAR reduction and precoding algorithm that relaxes these linearity requirements in massive multiuser (MU) multiple-input multiple-output (MIMO) wireless systems. Concretely, we develop a novel alternating projections method, which limits the PAR and transmit power increase while simultaneously suppressing MU interference. We provide a theoretical foundation of our algorithm and provide simulation results for a massive MU-MIMO-OFDM scenario. Our results demonstrate significant PAR reduction while limiting the transmit power, without causing EVM or OOB emissions.
翻译:在本文中,我们建议采用新型的全频分解和预编码联合算法,放松大型多用户(MU)多投入多产出无线系统中的线性要求。具体地说,我们开发了一种新的交替预测法,限制PAR和传送功率增加,同时抑制MU的干扰。我们提供了算法的理论基础,并为大规模MU-MIMO-OFDM情景提供了模拟结果。我们的结果显示,在不引起EVM或OOOB排放的情况下,PAR在限制传输能力的同时,大幅度削减了传输能力。