一种稀有的贝叶斯技术来学习OFDM无线系统中的频域主动回归器
Carlos Crespo-Cadenas1, María José Madero-Ayora1, Juan A Becerra1
1Departamento de Teoría de la Señal y Comunicaciones, Escuela Técnica Superior de Ingeniería, Universidad de Sevilla, Camino de los Descubrimientos, s/n, 41092 Seville, Spain.
Sensors (Basel, Switzerland)
|July 30, 2025
概括
本研究介绍了一种频域Sparse Bayesian Learning (SBL) 算法,用于模拟用于直角频率分割复合 (OFDM) 系统的功率放大器 (PA) 中的非线性扭曲. 这种新方法提供了与时间域方法相比较的准确性,但对于更广泛的带宽,效率显著提高.
科学领域:
- 电气工程 电气工程
- 信号处理 信号处理
- 无线通信无线通信
背景情况:
- 功率放大器 (PA) 的非线性行为建模对于无线系统至关重要.
- 大多数研究都集中在时间域 (TD) 建模上,在频域 (FD) 中的探索有限.
- 正角频率分割复杂化 (OFDM) 系统为FD建模提供了机会.
研究的目的:
- 开发和演示一个频域Sparse贝叶斯学习 (FD-SBL) 算法,用于无线OFDM系统中模拟非线性扭曲.
- 为了确定PA行为模型的有效和准确的减少回归器集.
- 为了能够预测连续的OFDM符号的非线性扭曲.
主要方法:
- 为PA非线性扭曲建模提出了一种新的FD-SBL算法.
- 利用SBL来识别活跃的FD回归因和估计PA模型系数.
- 应用估计系数用于预测后续OFDM符号中的扭曲.
主要成果:
- 对于30MHz带宽信号,实现了 -47dB的标准化平均平方误差 (NMSE) 验证,与TD-SBL (-46.6dB) 相似.
- 对于100MHz带宽信号,FD-SBL表现出卓越的性能,产生了-38.6dB的NMSE.
- 在100 MHz带宽上,TD-SBL遇到了过度的处理时间和数值问题,使其变得不切实际.
结论:
- 拟议的FD-SBL算法为OFDM系统中的非线性扭曲建模提供了一种高效准确的方法.
- 对于高带宽信号,FD-SBL克服了TD-SBL的计算限制.
- 这种方法有望提高现代无线通信系统的性能和效率.
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