Abstract: Methods are provided for determining and enhancing the service efficiency of mobile communications. To assess communication efficiency in each communication region of interest, a signal-fading record is generated for that region and this record is then analyzed to find availability and energy cost for each of a plurality of power-control parameter sets. The results facilitate the selection of power-control parameter sets that enhance system efficiency in each communication region.

Abstract: An improved mobile digital radio system is disclosed. A plurality of satellites and terrestrial repeaters transmit substantially identical information that is contained in an original time division multiplexed data stream. Each satellite transmits on a separate frequency band, and all terrestrial repeaters transmit on one shared frequency band. A mobile receiver simultaneously processes the frequency bands. The receiver selectively parses and concatenates a plurality of time division multiplexed data streams to substantially recompose the original data stream. The output may be a high fidelity audio signal, data for display, or a combination of audio and displayed data.

Abstract: Methods are provided for determining and enhancing the service efficiency of mobile communications. To assess communication efficiency in each communication region of interest, a signal-fading record is generated for that region and this record is then analyzed to find availability and energy cost for each of a plurality of power-control parameter sets. The results facilitate the selection of power-control parameter sets that enhance system efficiency in each communication region.

Abstract: Methods are provided for determining and enhancing the service efficiency of mobile communications. To assess communication efficiency in each communication region of interest, a signal-fading record is generated for that region and this record is then analyzed to find availability and energy cost for each of a plurality of power-control parameter sets. The results facilitate the selection of power-control parameter sets that enhance system efficiency in each communication region.

Abstract: A dual purpose receiver operable both on FM analog (voice) and MSK digital (data) signals has a demodulation section having a selectable time delay D.sub.1 for processing MSK digital signals and a time delay D.sub.2 for processing FM analog signals. A switch permits selection of the time delay for the demodulating mode desired. A second switch set according to how the first switch is set connects a digital processing circuit or an analog processing circuit to the output of the demodulation section. Small frequency errors due to frequency drift of the local oscillator or signal source and doppler effects can be eliminated by an automatic frequency control (AFC) circuit responsive to the output of the demodulator in the analog mode, and through a third switch responsive to a signal developed by mixing the input signal with the input signal delayed by a time delay D.sub.1, and mixing the output of that mixer with the binary output of the receiver in the MSK mode.

Abstract: A method and system is disclosed which provides precise multi-function digitally implementable modulation for a communication system. The invention provides a modulation signal for a communication system in response to an input signal from a data source. A digitized time response is generated from samples of a time domain representation of a spectrum profile of a selected modulation scheme. The invention generates and stores coefficients for each input symbol in accordance with the selected modulation scheme. The output signal is provided by a plurality of samples, each sample being generated by summing the products of a predetermined number of the coefficients and a predetermined number of the samples of the digitized time response. In a specific illustrative implementation, the samples of the output signals are converted to analog signals, filtered and used to modulate a carrier in a conventional manner.

Abstract: A transmitter for digital radio communication creates a null by balanced encoding of data modulated on an RF carrier, and inserts a calibration tone within the null. By having the calibration tone coincide in phase and frequency with the transmitted radio frequency output for coherent demodulation of data at the receiver where the tone calibration signal is extracted and used for multipath fading compensation.