COCHANNNEL INTERFERENCE MEASURING METHODS FOR DIGITAL MOBILE COMMUNICATIONS

In mobile communications in which the same frequency is repeatedly use d, the communication quality is degraded by co-channel interference fr om interference cells. To prevent this problem, it is necessary to kno w the amount of interference during communication. In this paper, an i nterference detection method applicable to PSK and FSK is proposed in which interference detection by the inverse modulation and decision er ror are used. In the case where coherent detection of pi/4-shifted QPS K is assumed, the characteristics are studied by computer simulation. We demonstrate that the SIR values can be measured over a wide range b y means of the proposed method. (C) Scipta Technica.