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Objective To systematically characterize the dynamic expression pattern, stage specificity and co-expression pattern of RNA-binding protein (RBPs) and to predict their potential regulatory role in mouse spermatogenesis. Methods The whole transcriptome sequencing data of six spermatogenic cells types were integrated for analyzing the differentially expressed RBPs during spermatogenesis;STEM was used to analyze the dynamic expression pattern of RBPs; WGCNA was used to identify the RBPs co-expressed pattern; The differentially expressed and co-expressed RBPs were analyzed by the ClusterProfiler tool for GO function enrichment analysis. Results A total of 519 stage-specific RBPs were identified during spermatogenesis, and there were 7 dynamic expression patterns, of which RBPs at the meiotic stage accounted for the highest proportion; GO enrichment analysis showed that RBPs were mainly involved in the selective splicing, processing or translation of mRNA; WGCNA analysis showed that 246 RBPs were co-expressed, among which RBPs at the meiotic stage accounted for the highest proportion. Conclusions RBPs exhibit stage specificity and play a regulatory role in spermatogenesis with a coordinated expression mode. It functions mainly in the process of RNA processing or splicing in the early stage of spermatogenesis, and is have significant impact on the process of ribosome assembly or RNA translation in the later stage.

The modified Cramer-Rao lower bound（MCRB） on symbol width estimation of a phase-shift-keying signal was derived.When calculating the integration of the square of dirac delta function δ（t ）, Parseval’s theorem was used to transform the computation from time-domain to frequency-domain.Then the closed-form analytical solution of MCRB for symbol width estimation was derived when the pulse shaping function was the rectangle pulse.However when the pulse shaping function was the raised cosine（RC） pulse, the MCRB is evaluated by numerical simulation.The results show that the MCRB of rectangle pulse shape is higher than that of RC pulse with the roll-off factor to be 0.5 and the dif-ference was about 1 dB.

The blind carrier frequency estimation of multi-phase shift keying（MPSK） signals was discussed.The carrier frequency was coarsely estimated without the prior knowledge of received signals.Consequently the signals were trans-formed to the baseband-modulated PSK signals by correlation to estimate the symbol rate.With the estimations of the carrier frequency and the symbol rate,the problem of carrier frequency estimation was converted to that of frequency offset.Because the phase of baseband-modulated PSK signal is a piecewise linear function and the slope coefficient of every segment is a linear function of frequency offset,the multi-segment line can be transformed to a straight-line and then the least squares fitting method was applied to estimate the slope coefficient.The simulation results show that this method can accurately estimate the carrier frequency without the prior knowledge.