| 摘要 |
<p>A communication breaking device 20 causes a PN-code generator 38 and a delay correcting unit 40 to advance the phase of a PN code sequence extracted by a receiving antenna 21, wide-range amplifiers 22 and 26, a multiplier 24, a BPF 28, a carrier-wave detector 32, a divider 34, a synchronization trapping unit 36 and a PN-code generator 38. An inverted-code generator 41 inverts the PN code sequence into an inverted code sequence. The inverted code sequence is transmitted by a multiplier 42, an electric-power amplifier 44 and a transmitting antenna 47. The inverted code sequence, which is transmitted as a communication breaking wave, is formed into a code sequence in the form of inversion of a pilot signal conforming to CDMA system. Moreover, the phase of the inverted code sequence has been advanced. Therefore, the pilot signal, which is being propagated, can appropriately be compensated with the advanced inverted code sequence. Thus, a fact can be recognized by a portable telephone that the portable telephone is deviated from a communication area for the base station. <IMAGE></p> |
