Fransimission Technology For Meteor Burst Communication

A meteor burst communications (MBC) system uses ionized meteor trails as a means of radio signal propagation. It has the inherent characteristics of intercept resisting, jam resisting, nuclear survivability and being well suitable for long-range communication. Time-varying bursty nature of MBC makes it important to make full use of the burst channel. A meteor burst channel can only be fully exploited when the actual data-rate is matched to the instantaneous power received from a meteor trail.Two meteor burst communication modes are investigated in the thesis. One is the single-carrier (SC) mode for extremely low SNR channel condition, the other the multi-carrier (MC) mode for high SNR scenario. For the SC mode, cyclic code shift keying (CCSK) is presented. Extended m-sequences are comprehensively studied for their correlation properties so as to construct the optimum CCSK base sequence. Simulations show that the raised scheme can afford reliable communication under-26dB low SNR condition. For the MC mode, analysis and comparison of various peak-to-average power ratio (PAPR) reduction techniques are firstly given. The effectiveness of the clipping scheme is studied in terms of total degradation (TD) while taking into account the effect of the nonlinear power amplifier, and the complementary cumulative distribution function (CCDF) of the instantaneous PAPR of the exponential companding signal is theoretically analyzed. Then, Turbo product codes (TPC) are studied for their performance in the exponential decay underdense channel. To reduce the decoding complexity, an efficient Chase decoder with no performance degradation is designed. Computer simulations show that data-rate of630kbit/s can be guaranteed under-5dB SNR condition.