Shortwave Burst Mpsk Blind All-digital Receiver

Short-wave communication is the most important scheme in military communication. With the fast development of various new technology and new systems, such as DSP technology, Micro processing technology, frequency-hopping technology, error correction technology ,Short-wave communication has already been widely applied in military communication, marine communication , board communication and so on. Blind receiving technology is helpful for the improvement of stability and transmission efficiency in short-wave communication. This thesis adopts 8PSK/QPSK modulation mode that's widely applied in Short-wave communication to research all-digital blind receiver in burst mode based on software radio technology. Then related solutions are given for the Doppler frequency shift problem and multiple fading problem in short-wave channels.The arrangement of the thesis is below:Chapter 1 gives brief description for the new technology and new systems of short-wave communication and for the development and appliance of software radio.Chapter 2 introduces the key technology for all-digital receivers.Chapter 3 gives a synchronization scheme for burst mode QPSK based on DPLL using a certain preamble first, then a short-wave burst-mode 8psk all-digital blind receiver is proposed., all of the scheme is demonstrated in detail., computer simulation result is given finally.Chapter 4 gives a way to deal with the Doppler frequency shift in some occasions when transmission speed is very slow.Chapter 5 applies Godard blind equilibrium algorithms to 8psk signal affected by multiple fading and the equilibrium performance testing result is given .