Research On The Third Generation HF Automatic Link Establishment Protocol

The domestic research on third generation HF communication came late and most of the HF radio stations are based on second generation. The requirements of third generation high frequency(3G-HF) radio technology were defined in U.S. MIL-STD-188-141B APPENDIX C. High performance DSP already is of the ability of processing high-speed real time signals. With these foundations, this paper focuses on scheme design of third generation HF Automatic Link Establishment (ALE) protocol, the key technologies about physical layer, and implementation on DSP hardware platform.First, the third generation HF Automatic Link Establishment protocol and the form of burst waveform of physical layer are introduced in this paper. Then, the practical scheme of protocol of automatic link establishment has been designed. Considering the effect of noise, fading, doppler shift and multipath, some technologies are adopted in the schemes to overcome these obstacles, including CRC, convolutional coding, interleaving, wave generation, sliding correlation-FFT technique and so on. The sending and receiving of BW0 are implied with these key techniques.Then all the programming tasks based on above scheme of automatic link establishment and physical layer are completed with compile language on DSP. Finally we test the performance of link establishment and the results are provided.