Patent US 5,459,702

A dictation system is disclosed which includes circuitry for eliminating or substantially reducing the effect of uncontrollable ambient noise typically found in a passenger compartment of a moving vehicle. The system utilizes or incorporates, for example, the vehicle's radio receiver and can be used to record local dictation or reception of audio from a remote location by means of a cellular telephone. One feature includes compression of speech during dictation to minimize transmission time from the vehicle to a remote base location for transcription.