Abstract: A stereo decoder is provided for decoding an encoded stereo signal. In one form, the encoded stereo signal is digitized and coupled to two sampling circuits. By selectively sampling the encoded signal relative to a stereo pilot signal contained in the encoded signal, both a left-hand audio signal and a right-hand audio signal may be separately recovered from the encoded signal and latched. A phase locked loop monitors the phase of the stereo pilot signal relative to the encoded signal and controls the time sampling of the encoded signal at predetermined phases of the pilot signal. The stereo decoding may also be performed by using analog circuitry to directly time sample the encoded stereo signal. In an analog approach, the time sampled output signal must be low pass filtered to provide decoded stereo output signals.

Abstract: A receiving system is disclosed that substantially instantaneously receives an RF signal. The inventive receiving system may be advantageously utilized at a central station of a mobile radio system for providing an omnidirectional receiving pattern. Both voice and digital information signals modulated on the RF signal transmitted from a mobile station are substantially instantaneously acquired by the central station. The receiving system includes an omnidirectional antenna configuration having a plurality of spatially disposed directional sector antennas, converting circuitry for converting the RF signals received by each directional sector antenna to an IF signal, IF bandpass filters for filtering each of the IF signals, and a maximal-ratio predetection diversity combiner for continuously combining the filtered IF signals to provide a composite IF signal so that any received RF signal is substantially instantaneously acquired.

Abstract: A communication system of the type wherein a central station assigns a limited number of information channels to a requesting one of a plurality of remote stations is disclosed. The requesting station sends its identification signal along with the request signal to the central station on a signal channel. The central station classifies the requesting station in either a priority or a non-priority queue. The priority queue corresponds to those stations which are continuing an on-going interchange, whereas the nonpriority queue contains those stations which wish to initiate an interchange. Stations are prioritized in the queues on a first-in/first-out basis.The central station constantly monitors the information channels and, as channels become available, assigns the channels first to stations in the priority queue, then to nonpriority queue stations.