Decoding algorithms with strong practical value not only have good decoding performance, but also have the computation complexity as low as possible. For this purpose, the paper points out the modified min-sum decoding algorithm(M-MSA). On the condition of no increasing in the decoding complexity, it makes the error-correcting performance improved by adding the appropriate scaling factor based on the min-sum algorithm(MSA), and it is very suitable for hardware implementation. Simulation results show that this algorithm has good BER performance, low complexity and low hardware resource utilization, and it would be well applied in the future.

This article presented a rotary self-check phase unwrapping algorithm. The algorithm was mainly to process phase unwrapping for the phase main value got from Interferometer in accurately measuring object surface topography, and then accurately restored the object surface topography. The object surface topography measured by Interferometer generally tended to be smooth, the phase unwrapping was not difficult without noise interference. The algorithm processed phase unwrapping by the path of gradually rotational diffusion from the middle to the around in the wrapped phase map, at the same time the check for the error was carried out. It used the median filter technology to process the phase unwrapping error, and avoided the transmission of phase unwrapping error, had a greater inhibitory effect on the noises. This method did not identify the residuals, had small amount of operations, and Unwrapping velocity was several times faster than the fastest traditional branch blocking algorithm.

In this paper, we propose the modified minsum decoding algorithm of LDPC(Low-Density Parity-Check) code in the simplified difference-domain on the basis of detailed analysis of LDPC decoding algorithm in difference-domain. The simulation indicates that the proposed decoding algorithm offers almost no performance degradation compared with the BP(Belief Propagation) decoding algorithm in log-domain and the decoding algorithm in difference-domain and offers better performance than minsum decoding algorithm in log-domain and greatly reduces the computation complexity in AWGN(Additive White Gaussian Noise) channel and under BPSK(Binary Phase Shift Keying) modulation.

The scheme of FPGA hardware implementation based on the RA structure of encoder for q-ary LDPC codes as well as the Max-log-BP decoding are designed emphasisly. Form the performance, speed, and resource consumption situation of coder and decoder, this scheme based on FPGA can meet the requirements of the most of communication systems.

Low temperature self-propagating forming coating material system for aluminum alloy cylinder parts was designed with Al, Fe2O3, Mo, Cu, Ni and Ti powders as raw materials. Low temperature self-propagating wear-resistant coating was prepared on the inner wall of aluminum alloy cylinder parts by thermal spraying ignition condensation centrifugal self-propagating fusion technology. XRD, DSC and SEM were used to study the microstructure, thermodynamic properties and cross-section morphology of the coating after thermal reaction of four kinds of low-temperature self-propagating materials with different proportions. The preparation process parameters of the coating were optimized by orthogonal test, including the amount of coating, the rotation speed of self-propagating centrifuge and the reaction time of self-propagating coating. The results show that the addition of Si, Mo and Zn powders in the four low temperature self-propagating powder systems can reduce the occurrence temperature of aluminothermic reaction; the optimal process parameters for coating preparation are rotational speed of 2000r/min, powder filling amount of 0.9g/cm3 and rotational reaction time of 16S.The results show that the coating with 20wt.% Al, 60wt.% Fe2O3, 12wt.% Si, 4wt.% Mo and 4wt.% Zn has better density and interface adhesion.