Abstract: In a communication system having Low Earth Orbit (LEO) satellites (210), one or more Mission Operations Control Centers (MOCCs) (220), one or more Distributed Virtual Network Managers (DVNMs) (230), and several types of Customer Premises Equipment (CPE) (250, 260, 270, and 280), individual service providers (20) are able to control the network services they provide independently from other service providers (20) through local management of the DVNMs (230).

Abstract: A speech coder (100) computes scalar statistics (180), ensemble statistics (190), spectral parameters (150), and a normalized excitation waveform (270) which describe a frame of speech samples. The coder (100) encodes the statistics (220, 230), spectral parameters (155), and the normalized waveform (290) for later decoding and synthesis. A speech synthesizer (900) decodes the encoded scalar statistics (570), encoded ensemble statistics (560), encoded spectral parameters (490), and encoded normalized excitation waveform (550). The synthesizer (900) then denormalizes (670) the normalized excitation waveform using the scalar statistics and the ensemble statistics, resulting in a decoded excitation waveform. Speech is synthesized (710) from the decoded excitation waveform and the decoded spectral parameters.

Abstract: The method and apparatus of the present invention uses DSI with a TDMA/FDMA communication protocol. For each speech frame detected by a speech detector (110), a communication unit (CU) (108) sends (440) a speech detected indicator (SDI) (208) to a switching facility (SF) (138). In response, the SF (138) allocates an uplink reuse unit (260) which identifies a carrier frequency (301-360) and timeslot (190-193) which the CU (108) should use to transmit a traffic burst containing a compressed speech frame. The SF (138) allocates (506) the uplink reuse unit (260) from a pool of available uplink reuse units and, if necessary, allocates a downlink reuse unit (262) from a pool of available downlink reuse units. A message (220) describing the reuse units (260, 262) is transmitted (508) to the CU (108) which then transmits (450) and receives (480) traffic bursts during the allocated reuse units (260, 262).

Abstract: A Doherty-type active bias power amplifier (90) suitable for satellite telecommunication systems provides linear amplification of noise-like RF input signals (100) that have multiple carriers spread over a large instantaneous bandwidth. As RF input signal (100) to active bias power amplifier (90) increases, the negative pinch-off voltage that normally causes development of a negative voltage on the gate/base is precluded from occurring in the carrier amplifier (115) and thus an improvement in RF output power is achieved as well as an increase in the dynamic RF input drive range over which high efficiency operation can be achieved. Active biasing provides the proper bias-on point for the peaking amplifier (135) in order to achieve maximum RF efficiency operation.

Abstract: Multiple satellites are densely packed in modern multi-satellite launch vehicles. Stocking of a subsequent satellite (20) in the presence of adjacent satellites (12) subjects both satellites to damage due to mishandling and human error during craning operations. An alignment mechanism (30) attaches to subsequent satellite (20) and operates in conjunction with a craning tether (26) to stock a launch vehicle dispenser (10) with subsequent satellite (20). An alignment mechanism (30) restricts lateral motion of subsequent satellite (20) during stocking while keeping subsequent satellite (20) centrally located in a vacant position on a launch vehicle dispenser (10).

Abstract: In a data synchronizer a timing error estimator samples a received data stream and generates a clock to provide optimal sampling of the data stream, and a lock detector monitors the clock and received data stream to provide an indication of whether optimal sampling has been achieved. The lock detector processes differences between delayed versions of the input which are sampled based upon the clock timing. These sampled differences are then processed by a non-linear circuit to provide a lock signal indication which, when compared to a predetermined threshold signal, is used to provide optimal sampling indication. The lock detector performs computations on real and complex inputs and therefore is compatible with a wide variety of modulation types. The lock detector can be implemented in either analog or digital circuits, making it applicable to a broad range of data synchronizer applications.

Abstract: A satellite communication system for delivering simplex messages to subscribers comprises multiple Message Origination Controllers (MOCs), one or more Message Termination Controllers (MTCs), satellites, and geographically-diverse communication units. Messages destined for particular communication units are transmitted to the one or more MTCs. The one or more MTCs then schedule delivery of the messages to communication units by employing a blocked timing structure for delivery of the messages. The one or more MTCs transmit the scheduled messages to satellites which broadcast the messages to communication units at the scheduled time. Communication units are assigned specific timing blocks during which they monitor radio signals for messages directed to them. During non-assigned timing blocks, communication units remain in a low-power state.