Research On Link-11 Technique System For HF Tactics Data Link

Link-11 is one of the tactics data links which are active-duty in the army of USA, and its single tone Link-11 waveform(SLEW) is adopted by the HF waveband of Link-22,so whether based on considering of present strategy or research of Link-22 in the future or developing our tactics data link, it is concernful to study the SLEW mode of Link-11.First, several tactics data links of the USA and their history are introduced in this thesis, then composition of a Link-11 system, work mode and technique of CLEW are described, at last a SLEW transmiting and receiving mode based on a in-depth study of Link-11 standard is given.When the transmiting mode is designed, analysis and simulation of CRC, Punctured tail-biting convolutional block coding, block interleaving, gray mapping, scrambler, 8PSK-modulation are finished.When the receiving mode is designed, the proformance of LMS and RLS algorithms is analyzed firstly, and considering the characteristics of SLEW, the RLS algorithm is selected as the channel equalization algorithm. Based on simulation, the action of gray mapping and block interleaving for the improvement of the performance of the above mode is discussed. Through comparison, a decoding algorithm for tail-biting convolutional block coding: fixed delay Viterbi decoding algorithm is introduced and improved, then a decoding algorithm for punctured tail biting convolutional block coding is discussed and its performance is compared with decoding algorithm for tail-biting convolutional block coding. The performance of the above mode is given at last.