In this letter, we propose a near-optimal low-complexity frequency-domain (FD) harmonic receiver for visible light communication based unipolar frequency-shift keying (U-FSK). The time-domain (TD) maximum-likelihood (ML) receiver for U-FSK is computationally complex, while the sub-optimal receiver increases the noise variance. The proposed harmonic receiver determines the transmitted frequency from the cross-correlations between the FD received waveform and the FD dictionary waveforms reduced to their strongest harmonics. The results shall demonstrate that besides affording a linerarithmic complexity, the performance of the harmonic receiver closely approaches that of TD ML receiver which exhibits quadratic complexity.

中文翻译：

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用于单极 FSK 的近乎最优的低复杂度谐波接收器

在这封信中，我们提出了一种近乎最优的低复杂度频域 (FD) 谐波接收器，用于基于单极频移键控 (U-FSK) 的可见光通信。U-FSK 的时域 (TD) 最大似然 (ML) 接收器在计算上很复杂，而次优接收器会增加噪声方差。所提出的谐波接收器根据 FD 接收波形和 FD 字典波形之间的互相关来确定传输频率，并减少到它们的最强谐波。结果将证明，除了提供线性复杂度之外，谐波接收器的性能与表现出二次复杂度的 TD ML 接收器的性能非常接近。