Abstract: A satellite communications system having ground user terminals, hubs, and a geosynchronous satellite. The satellite generates a network of spot beam coverage areas on the earth. A hub and at least one ground terminal are located in each of at least two spot beams. A first user terminal transmits an uplink signal according to a first signal protocol to the hub through the satellite. A second user terminal receives a downlink signal according to a second signal protocol through the downlink spot beam from the hub through the satellite. The hub may be located in the same spot beam coverage area as the first or the second user terminal or may be located in an altogether different spot beam coverage area.

Abstract: A method for optically switching a signal in a two-way communication system using only one satellite includes the steps of receiving a first set of N beams, forming a first set of N optical channels from respective ones of the N beams, spreading each of the N optical channels in one dimension to irradiate a first N.times.M array, switching a signal existing at one position of the first N.times.M array to any position of a second N.times.M array, unspreading the signals from the second N.times.M array to form a second set of N optical channels, forming a second set of N beams from the second set of N optical channels; and thereafter transmitting the second set of N beams which service M customers simultaneously.

Abstract: A communication system that reduces significantly the processing required to search over unknown time delays and unknown frequency shifts. Convolutional type processing with a unique re-indexing of the desired signal's Fourier transform is provided so as to allow for the design of a communication system that is invariant to time of arrival and frequency shift such as that caused by doppler effects from moving vehicles or moving satellites. The processing required is several orders of magnitude less computationally intensive than conventional approaches to solving this problem. In addition, the inventive convolutional ambiguity multiple access (CAMA) system can be used in conjunction with M-Ary FSK (Frequency Shift Keying) and other coding techniques to decode the various frequency codes efficiently.

Abstract: An optically-based communication system hosted on an elevated platform (e.g., a satellite a tower, or other platform having a substantial vantage point) that uses multiple spatially diverse transmit and receive beams that are optically cross coupled to fully reuse the spectrum and which will create a fully interactive, high bandwidth, high capacity, fully switched communication system. The elevated platform (i.e., satellite, orbiting or tethered vehicles, airborne platforms, towers, etc.) reuses its assigned bandwidth in each of (N) multiple beams (or sectors). The beams are formed by either RF or optical means. The specific users in each beam are then spatially separated in frequency by use of an optical "Bragg Cell." The separated signals are then duplicated through a half mirror and a full mirror and recombined optically to create outputs that are unique combinations of frequencies from each full set of input beams.

Abstract: A high capacity communication satellite uses a large number of parallel beams and optical processing to effect a fully interactive, high bandwidth, high channel capacity fully switched communication system. The satellite reuses its assigned bandwidth in each of the multiple beams. The beams are formed by either RF or optical means. The specific users in each beam are then separated optically using spatial light modulation (SLM) array correlation techniques. A single large SLM, or multiple smaller SLMs in combination, may be used. The individual customers are then repositioned in the array by optical SLM mixing and recorrelation. The result is then remodulated by another SLM array used as a mixer, and then recombined to reform the appropriate outgoing beams. The entire system then becomes a fully switched, high bandwidth, high channel capacity communications network on a single satellite.

Abstract: A system and method are provided for use in training individuals in biofeedback techniques. A variety of physiological functions are monitored on separate channels and associated circuitry generates feedback signals for each function. The feedback signals from the various physiological functions preferably are combined in a matrix from which an output is generated only under predetermined conditions as when two or more of the monitored functions are within the parameters set for each separate function.