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It describes that a large variety of new applications could be implemented in the future under severe environment of ground and space by combining the SpaceWire and wireless communication protocols such as IEEE 802.11. In view of the burst errors and random errors on its wireless channel in the complex environment, this paper suggests the concatenated code of RS(255,223)+Convolution(2,1,7) as a good error control scheme. The concatenated codec is analyzed by Matlab/Simulink on the AWGN channel with burst interference; then with the tool of Xilinx System Generator, the concatenated codec built on model-based design is completed later. At last the verification platform called SignalWAVe implements Hardware Co-simulation of the FPGA model. As the result shows, the concatenated code communication system can obtain an ideal bit error rate if the signal-to-noise ratio is low enough. It’s proved that the scheme is good.

DURING a survey of the southern sky for millisecond pulsars, we have discovered one with by far the greatest flux density of any known millisecond pulsar, often exceeding 1 Jy at 430 MHz. The dispersion measure (integrated electron density along the line of sight) is the smallest for any known pulsar. This object, PSR J0437–4715, may be the closest known pulsar, and is several times closer than any other known millisecond pulsar. Its rotation period is 5.75 ms, and it is in a 5.7-day circular orbit with a low-mass companion. The spin-down energy flux density is the third highest known, after the Crab and Vela pulsars. These properties make possible studies of the pulsar at radio wavelengths with unprecedented detail, and indicate that it should be possible to detect both the pulsar and its companion at optical and perhaps shorter wavelengths.