Abstract:

This paper gives an ultra wideband (UWB) communication system based on parallel combinatory spread spectrum, which composites the advantages of the security and the high efficiency of UWB communication system and parallel combinatory spread spectrum communication system. So the new system can possess the high efficiency and the fine security simultaneously. In the new system the signal output from the part of the parallel combinatory spread spectrum has the property of nonequal probability. And the error probability of demodulation is presented for non equal probability time hopping M ary pulse amplitude modulation (TH MPAM), and the equation is proved to be correct by means of simulation. Under the background of the additive white Gaussian noise, the paper gives the simulation of the bit error rate (BER) performance of the system. The results show that the new system is better than the normal parallel combinatory spread spectrum system and normal UWB communication system of the BER performance.