Abstract: In a digital radio-telephone receiver, an open-loop arrangement for generating a received-signal-strength-indicating ("RSSI") value suitable for use in mobile assisted hand-off within a cellular telephone system. The receiver has an amplifier for amplifying a received signal with a gain controlled by a gain-control signal, and an automatic-gain-control circuit ("AGC") responsive to the amplitude of the amplifier output and coupled in a feedback-loop for applying an AGC signal to the amplifier as the gain-control signal. An RSSI value is generated by (i) opening the AGC feedback loop so that the AGC output signal is not applied to the amplifier, (ii) applying a ramp signal of increasing amplitude to the VGA while the AGC monitors the signal envelope, and (iii) when the signal envelope passes a pre-selected threshold, applying the then-occurring ramp-signal value to a calibrated look-up table to obtain the corresponding RSSI value stored therein.

Abstract: A voltage-controlled oscillator includes a compensating signal value calculator which calculates the value of a function representing the portion of the oscillator temperature-frequency transfer curve corresponding to the ambient temperature. A signal corresponding to the calculated value is then applied to the voltage-controlled oscillator as the control voltage. Basically, an oscillator temperature-frequency transfer curve is partitioned into n segments. For each segment an offset value, x.sub.n, equal to the difference between the frequency at the start of the segment and the desired frequency, is stored in a look-up table. When a compensating signal value is required, the compensating signal value calculator retrieves from the look-up table the x.sub.n values corresponding to the segment immediately preceding and succeeding segment k, segments "k-1" and "k+1". The retrieved values are labeled x.sub.k, x.sub.k-1, and x.sub.k+1, respectively.