| Related researches are carried out against the key channel, i.e. signaling channel of mobile communication which mainly adopts time-division multiple address & code division multiple access currently, and the essey here talks about the interference problem of TDMA GSM communications. Against the status that moving communication interference is mostly made by noise blanketing jamming in home, the essey raises a new interference method, i.e.,making false signals to achieve barrage jamming of GSM communications network. Detaily, the essay analyses signal format of signal of PCH and RACH to get their specific meanings of each field respectively. Then, edit channel codes, modulate GMSK and emulate by MATLAB to get their I & Q time domain waveform. Also, three ways of interference using false signal are explained. Last part of the essay introduces briefly spread spectrum communicationand compares the interfere effect of wide-band noise jamming, narrow-band jamming and impulse jamming to CDMA communication system . |
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