According to the practical application of cab signaling device on railway site,a loss-free compression method for the waveform data recorded by cab signaling recorder based on integer lifting wavelet transform and Rice coding is proposed in this paper.

Considering the von Mises distribution as the received multipath power density distribution versus the AOA of scatter components, a formula for multipath angular spread corresponding to this distribution is presented in multi-antenna Rice channels, and an approximate expression for spatial correlation coefficient between compact antenna elements is proposed in small-scale Rice fading channels.

In this paper, for regular LDPC codes on Rice channel, DDE for BP,BP-based and offset BP-based decoding algorithm were compared on different quantization level and step.

Presents first image coding methods and then a new guality image compression method based on edge direction, by which an image is first partitioned into blocks and a direction predictor is then adaptively selected for each block with minimum prediction error and an efficient adaptive rice coder is then applied with residual image quantized.

Rice condition numbers of QR and Cholesky factorizations;

For the simulation of ship formation communication channel,a improved Longley-Rice model is presented to predicte the loss of radio wave propagation along the sea surface.

Starting with Free-Space propagation model, analyze typical radio propagation models such as Egli model, Okumura-Hata model, Longley-Rice model and Cost231-Hata model, find out their respective applied physical properties.

This paper analyzes backgrounds and applicable conditions for three models,and combines Matlab simulation with test data,chooses Longley-Rice model as the transmission-loss model for marine VHF/UHF communication.