Abstract: A system for facilitating global cellular/trunked mobile communication is disclosed. This system permits communication with hand held and mobile mounted cellular telephones. The system permits two-way communications anywhere on or above the earth up to a particular height above the earth of several hundred nautical miles. The system employs a number of low-earth orbiting satellites moving about the earth in orbit. Links are provided from the satellites directly to the users and via the public switched telephone network to other users. The satellites are interconnected via links in a ring structure surrounding the earth. Switching is performed by each of the satellites. In addition, each of the satellites hands off a call as it moves out of the range of a particular user.

Abstract: A system for facilitating global cellular/trunked mobile communication is disclosed. This system permits communication with hand held and mobile mounted cellular telephones. The system permits two-way communications anywhere on or above the earth up to a particular height above the earth of several hundred nautical miles. The system employs a number of low-earth orbiting satellites moving about the earth in orbit. Links are provided from the satellites directly to the users and via the public switched telephone network to other users. The satellites are interconnected via links in a ring structure surrounding the earth. Switching is performed by each of the satellites. In addition, each of the satellites hands off a call as it moves out of the range of a particular user.

Abstract: A power management system for a worldwide multiple satellite system having satellites positioned latitudinally in a polar orbiting constellation, each satellite having a plurality of antenna beams, each beam having a given area of coverage or "cell," the total sum of the cells for each satellite forming a larger coverage for the entire satellite, the satellites each comprising solar cells and batteries wherein the energy within the batteries is generated by the solar cells and must be efficiently managed. The system comprises an earth based control station which programs each of the satellites within the constellation to supply power to the antenna beams of each satellite at predetermined times to avoid overlapping coverage. Each satellite comprises a voltage regulated linear power amplifier to supply only the power needed for the demand within each of the antenna's cells.

Abstract: A Telemetry, Tracking and Control (TT&C) system for a satellite cellular communication system utilizing one of the user voice/data communication channels to communicate TT&C data with a satellite and through one satellite to other satellites. A Global Positioning Receiver (GPS) on board each satellite provides position control signals to the on board satellite control subsystem and the GPS receiver communicates ephemeris information to a ground station through the cellular user data channel. The system allows for constant TT&C communication to and from a mobile ground station and to and from any satellite.

Abstract: A method of predicting cell-to-cell hand-offs of mobile subscribers for a satellite cellular communications system. Each satellite of a constellation projects a number of beams or cells upon the earth for communication with mobile subscribers. The satellite transfers (hand-offs) communications links from cell to cell as the satellite moves over the mobile subscriber. Since the movement of the satellite is stabilized in three directions, the projection of the beams or cells follows a predictable path across the face of the earth. Each satellite moves across the earth in one direction. Once a subscriber is located within one cell, the next cell to which the mobile subscriber is handed-off may be determined from the geographic position. For mobile users which are close to boundaries between cells, additional position location may be determined by the calculation of bit error rates.

Abstract: A multiple beam space antenna system for facilitating communications between a satellite switch and a plurality of earth-based stations is shown. The antenna is deployed after the satellite is in orbit by inflation of a raft-type supporting structure which contains a number of antenna horns. These antenna horns are oriented in substantially concentric circular groups about a centrally located antenna horn. Each of the antenna beams projects an area on the earth. Each of the areas of the beams are contiguous. As a result, one large area is subdivided into many smaller areas to facilitate communications. In addition, a lens may be employed to focus the beams of the horn antennas.

Abstract: Wave soldering is accomplished in an enclosure having an atmosphere which is substantially free of oxygen and which provides a fluxing action due to the presence of a gaseous reducing agent. A conveyor carries articles to be soldered through the enclosure by means of an entrance and exit which are provided with gas curtains to inhibit atmosphere exchange with the ambient air.