Repeater with RF channel selectivity and method of repeating for radio telephony systems going to mobile users

摘要

A repeater is described of particular application in cellular radio telephony systems and especially in the SCPC systems (such as the TACS system) and in systems corresponding to the GSM standard. The channel receivers RIC of the repeater for SCPC systems call for the presence of a carrier detector RV which orders the closing of a switch SW when it detects the presence of an RF signal with amplitude greater than a predetermined threshold. Such a repeater is also outfitted with a number of receivers RIC having channel selectivity less than the total number of RF channels assigned to said base radio station and it is provided with means able to scan all the RF channels and to stop the scan in a receiver when said carrier detector RV detects the presence of input signal RF. Each channel receiver RIC also comprises means AGC of regulating, or automatically limiting the gain of IF amplifiers G, able to intervene when the IF signal is above a predetermined level. IMAGE