Abstract: In plural channel amplifier systems processing many phase locked signals of different frequencies as a combined signal, these signals may drift into a phase convergence causing a peak power occurrence in the amplifier which greatly exceeds the rated capacity of the amplifier system. Therefore, in accord with the invention, a dynamic adjustment system is provided to minimize the peak power to which the amplifier is subjected by adjusting the relative phase relationships of the many signals. The dynamic adjustment system includes a peak power detector, a hard wired logic decision circuit and a timing control to control phase shift adjustment steps.

Abstract: Some cellular mobile radiotelephone systems use tones for certain call connection supervisory functions on radio links. The presence of the correct tone in a received radio channel call signal is determined by using the received signal for producing (32) a lower frequency tone that is readily selectable (36) from similar tones produced in response to incorrect supervisory tones. Circuits are also shown for separately processing received call signals to produce (41, 53) supervisory tone phase information that is indicative of range between communicating stations. Several circuits (72; 40 and 46; 59-62) are shown for enhancing the accuracy of the produced phase information of the correct tone.

Abstract: Some cellular mobile radiotelephone systems use tones for certain call connection supervisory functions on radio links. The presence of the correct tone in a received radio channel call signal is determined by using the received signal for producing (32) a lower frequency tone that is readily selectable (36) from similar tones produced in response to incorrect supervisory tones. The same received call signal is also separately processed to produce (41, 53) supervisory tone phase information that is indicative of range between communicating stations. Several circuits (72; 40 and 46; 59-62) are shown for enhancing the accuracy of the produced phase information of the correct tone.

Abstract: The signal-to-noise ratio of intermittent reception by a radio receiver from a push-to-talk transmitter is measured by comparing AGC voltage levels derived from a signal period with levels derived from the prior no-signal period containing noise only. The AGC voltages are applied to a pair of integrators having corresponding time constants and therefore normally having equal outputs. When a valid signal period is recognized, the output of one integrator is held to represent an integration of voltage levels during the prior no-signal period. The integrated signal thus held is thereafter compared with the running output of the other.