Abstract Precoding technique is proposed and experimental demonstrated to resist sampling frequency offset (SFO) in W-band OFDM RoF systems. Walsh–Hadamard transform (WHT)-precoding, discrete Hartley transform (DHT)-precoding, Zadoff–Chu transform (ZCT)-precoding, and orthogonal circulant matrix transform (OCT)-precoding are investigated and compared. SFO-induced inter-carrier interference (ICI) on each subcarrier of conventional OFDM and OFDM with precoding (precoded-OFDM) are theoretical analyzed. Experimental results indicate OFDM with OCT-precoding (OCT-OFDM) can obtain a remarkable resistance to the SFO-induced ICI in W-band OFDM RoF systems.

中文翻译：

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W-band OFDM RoF系统中基于预编码技术的增强采样抗频偏方法

摘要 提出并实验证明了预编码技术可以抵抗W波段OFDM RoF系统中的采样频率偏移（SFO）。研究并比较了 Walsh-Hadamard 变换 (WHT) 预编码、离散 Hartley 变换 (DHT) 预编码、Zadoff-Chu 变换 (ZCT) 预编码和正交循环矩阵变换 (OCT) 预编码。对传统OFDM和预编码OFDM（precoded-OFDM）的每个子载波上的SFO引起的载波间干扰（ICI）进行了理论分析。实验结果表明，带有 OCT 预编码的 OFDM (OCT-OFDM) 可以在 W 波段 OFDM RoF 系统中获得对 SFO 引起的 ICI 的显着抵抗。