Importance

Loading Importance Indicators...

Abstract

A paging device includes a radio receiver (10-20) and decoding circuitry (22) for receiving an encoded transmitted signal and operates an indicator (26) to alert a user that a call has been received. A signal strength detector (30) monitors the strength of a carrier for a transmitted signal and provides a voltage level proportional to the carrier signal strength. A switch (33), when enabled, connects the voltage level from the detector (30) to a voltage controlled oscillator (32) which provides an output having a frequency proportional to the monitored strength of the carrier signal. The output of the variable frequency oscillator (32) is connected to the indicator (26) to provide the user with an indication of whether transmissions may be reliably received. The variable frequency oscillator may be replaced by a threshold device (35) to simplify the paging device, or the basic system may be provided with an averaging device (27) so that the user may select between instantaneous and average values of the strength of the monitored carrier signal. In an alterative embodiment, the paging device may be implemented using a microprocessor (23) controlled by a program stored in ROM (25) as the decoder. In this implementation, the microprocessor may be programmed to perform additional functions including computing the error rate of decoded messages, and if the error count exceeds a predetermined threshold, alerting the user of an unreliable radio link. A further refinement allows the user to monitor the error rate.

Loading the Abstract Image...

First Claim