Abstract: A method (1300) and apparatus (300) combines a terminal blockage profile for a ground-to-satellite terminal with satellite location and motion data for one or more satellites (12) in a satellite communication system (10) to predict an impending service outage or impairment on a real-time or near real-time basis and reports such impending outages or impairments, and the expected duration thereof, to the terminal operator. The prediction of an impending outage or impairment also can include analysis of information concerning atmospheric conditions in the vicinity of the terminal location as well as other potential sources of a service outage or impairment.

Abstract: A transmitter system (18) which transmits a communication signal (14) through a phased-array antenna (10) uses a signal processor (26) and a multiplicity of direct modulators (30). Each direct modulator (30) drives a single element (12) of the antenna (10). Each direct modulator (30) receives a digital baseband phase point data signal (62) from a digital data stream (28). The digital data stream (28) also conveys digital beam formation data (60). Each direct modulator (30) digitally combines the baseband phase point data (62) with the beam formation data (60) to produce digital streams that modulate an RF carrier signal (34). The digital data stream (28) is generated by a phased-array signal processor (26) which processes user data bits (86) received from any number of input signals (22) and processes beam signals (24). In one embodiment, the signal processor (26) calculates phase point data (62) representative of all input signals (22).

Abstract: A method and apparatus for combining and separating groups of signals starts by a transmitter (500) receiving a number of CDMA-encoded signals from data sources (510). The CDMA-encoded signals are sorted (502) based on their intended destinations. Those CDMA-encoded signals which are intended for a common destination are multiplexed (504) together into a group. The group is further CDMA encoded (506) using a group code and the encoded group is transmitted (508) to an intermediate transceiver (600) or a destination transceiver (700). The intermediate or destination transceiver decodes (604, 704) the group using the appropriate group code and routes the resulting group of signals accordingly.

Abstract: A satellite communications system employs CDMA multiple access technology. Polarizations are associated with each spreading code to enhance separation between simultaneous users in the absence of perfectly orthogonal spreading codes. A satellite transmitter CDMA encodes(210) and carrier modulates(220) a user or block of users, and then assigns a polarization to the user of block of users. A CDMA reference signal also receives a polarization. A ground receiver (30,40) receives the polarized CDMA signals as transmitted by the satellite. The ground receiver ascertains the polarization of the reference signal and then computes the polarization of the desired polarized CDMA signal. The use of the reference signal negates the effects of the faraday rotation caused by the satellite signal(10,20) passing through the ionosphere.

Abstract: A method and apparatus for routing signals through a system (10) which has multiple destination nodes (12, 14) assigns one or more unique carrier frequencies to each destination node (12, 14). When a signal is received (502) by a transceiver (12), the transceiver (12) evaluates (504) the carrier frequency of the signal, and determines (506) to which destination node (12, 14) that carrier frequency is assigned. The determination (506) is made using a table (200) which associates carrier frequencies to destination nodes (12, 14). The table (200) is created (304) and updated by a control facility (20) which distributes (306) the table (200) to the transceivers (12). Once the transceiver (12) determines (506) the destination node (12, 14), the transceiver (12) can route the signal toward that destination node (12, 14).

Abstract: A constellation (12) of satellites (14) distributed around the earth supports satellite-based communication system (10) involved in global communication of subscriber units (24). Subscriber units (24) may potentially transmit from any location on earth. Some locations such as radio astronomy sites (28) may be interfered with by nearby transmissions from subscriber units (24) or transmissions from satellites (14). Subscriber units (24) located within a potentially interfering proximity to radio astronomy sites are prohibited from transmitting potentially interfering signals by reception of a non-interfering control signal transmitted by a radio astronomy special equipment located at radio astronomy sites. A radio astronomy special equipment (44) repeatedly transmits to a subscriber unit (24) a control signal synchronous with a control signal of a servicing satellite. The radio astronomy special equipment control signal (46), (48), and (54) is compatible with a subscriber unit's communication receiver.

Abstract: An enhanced services communication system (10) has a standard services region and an enhanced services region (58) in which communication may be carried out. Subscriber units (49, 109) located within the enhanced services region (58) request enhanced services that include dynamic allocation of bandwidth. A variable bandwidth repeater switch (42) evaluates the availability of requested bandwidth and allocates the bandwidth to the subscriber units (49, 109) when available. Transmission of data using enhanced services occurs using wideband wired interfaces (115), wideband wireless interfaces (70), or PSTN interfaces (103). Selection of dynamic allocation of bandwidth may rely upon economic, propagation duration, or link quality factors, among other considerations.