| Summary: | 博士 === 國立交通大學 === 電信工程研究所 === 100 === In the dissertation, we first investigate the high-accuracy one-bit carrier phase estimation. Signal-to-noise ratio (SNR) is utilized to select the proper phase discriminator to achieve high accuracy. The traditional arctangent phase discriminator (APD) and the noise-balanced digital phase discriminator (NB-DPD) can obtain accurate carrier phase for low and high SNR, respectively, but both algorithms have estimation bias in moderate SNR. Therefore, the SNR-aided phase discriminator (SNRaPD) is proposed to obtain the accurate phase. Since the SNR information may be unavailable in many applications, we further extend the algorithm of SNRaPD to jointly estimate the phase and SNR. On the other hand, we propose a computationally efficient method, termed Phase Coherence Acquisition (PCA), for PN sequence acquisition by using complex phasors. In order to combat noise, the input and local sequences are partitioned and mapped into complex phasors in PCA. The phase differences between pairs of phasors are then utilized for code phase acquisition, and thus complex multiplications are avoided. The computation load of PCA is much less than that of the conventional fast Fourier Transform (FFT) method. Finally, the multi-layer PCA is developed to enhance noise-robustness.
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