Abstract: A system and method that provides satellite television users with a simple interface in which to choose from a variety of video images representing a different camera angle at a given event. The invention comprises a plurality of cameras positioned at a certain event, such as a sporting event. The video images from the cameras are broadcast to one or more satellites, which downlink the images to a central broadcast center. At the central broadcast center, information relating to the event is bundled with the video images and re-broadcast to a second set of satellites. The information and video images are then downlinked to multiple users situated within the satellite's footprint, to be viewed on their televisions.

Abstract: A method for selecting a transmission rate and coding scheme for transmitting data packets from a remote terminal to a hub includes performing a ranging process between the hub and remote terminal. The ranging process may be repeated for each of a number of different transmission rates and coding schemes. The remote terminal may then select the appropriate transmission rate and coding scheme based on the ranging.

Abstract: A radar surveillance system includes a plurality of satellites a plurality of medium earth orbit satellites to provide continuous, long dwell coverage of a region of interest. Each satellite has an antenna having a main reflector and a subreflector electromagnetically coupled to the main reflector. A phased array generates multiple electromagnetic beams positioned so the electromagnetic beams reflect from the subreflector onto said main reflector. The system may be used in determining slow moving targets using a combination of monopulse anomaly and target spectral width measurements. The system also performs synthetic aperture radar imagery and focussed area fast moving target detection using alternating slope linear frequency modulated pulses. The plurality of medium Earth orbit satellites include a self-contained communications system consisting of high bandwidth self-relay crosslinks, high bandwidth downlink, and direct broadcast downlinks for processed data.

Abstract: A method and apparatus for mitigating communications interference between satellite communications systems in different orbits is disclosed. The method comprises the steps of evaluating a geometrical relationship between a second ground station and the satellites in the second satellite constellation, and directing communications between the second ground station and the second satellite according to the evaluated geometrical relationship. In one embodiment communications are handed over from a first satellite to another satellite when the first satellite is no longer at the highest elevation angle of visible satellites. In another embodiment, handover occurs when the first satellite drops below a minimum elevation angle.

Abstract: A system and method for retransmitting data frames, which were inadequately received by a receiver, back to the receiver to increase receiver gain. Upon receiving a retransmission request from the receiver, the data transmitter retransmits a particular data frame to the receiver without transmitting a signaling message, and the receiver compares it to other data frames stored in a buffer. When a match is believed to exist, the receiver combines the retransmitted data frame with the matching data frame. Based on the result of a cyclic redundant code (CRC) check performed on the combined data frame, the receiver either provides the combined data frame to a higher layer in the receiver, or stores either the combined data frame, or the retransmitted and potentially matching data frame, in the buffer, depending on a confidence in the potential match, and sends another retransmission request to the transmitter to again retransmit the data frame and the above process is repeated.

Abstract: A method and apparatus for performing satellite selection in a broadcast communication system is provided. In some embodiments, a controlling data stream broadcast on a first satellite over a broadcast channel is utilized to indicate that information signals such as a television program are being carried on the same channel on a different satellite. Remote receiving apparatus utilize the controlling data stream to locate the information signals by switching to the satellite identified in the controlling data stream.

Abstract: A method, apparatus, article of manufacture, and a memory structure for multicasting data in a cellular personal access communication system is disclosed. The method comprises the steps of allocating a multicast packet terminal identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group, receiving a multicast packet having a global multicast address, determining a cell identifier from a mapping of the global multicast address to at least one local multicast identifier and a cell identifier, and forwarding the multicast packet to the cell according to the cell identifier. The apparatus comprises a radio port controller unit having a packet data control unit coupled to a radio port configured to receive a multicast packet and a packet forwarding module. The packet data control unit includes an allocation module configured to allocate a local multicast identifier to a multicast group when a subscriber unit in a cell requests membership in the multicast group.

Abstract: A method and apparatus for providing an integrated presentation of existing media program services and secondary media program services is described. The method comprises the steps of accepting a election of a secondary media program transmitted on a secondary media program channel; accessing a mapping to determine a primary media program channel associated with the selected secondary media program channel; commanding a first tuner module to receive conditional access information associated with the primary media program channel from the primary service provider; evaluating the conditional access information to determine if a second tuner is authorized to receive the secondary media program channel; and commanding a second tuner module to receive the secondary media program if the second tuner is authorized to receive the secondary media program channel.

Abstract: The present invention is described by an electronic program guide with a calendar tool, and a method and apparatus for transmitting and receiving the electronic program guide. The apparatus includes a transmission station and a plurality of receiver stations. The transmission station creates program guide data that is in an “object” format. The transmission station combines the program guide objects with digital audio and video television signals, and transmits an output stream to the plurality of receiver stations. Each of the plurality of receiver stations stores electronic program guide objects. Using data from the electronic program guide objects, the plurality of receiver stations generate a listing of television program representations, and a calendar image separate from and adjacent to the plurality of television program representations.

Abstract: A system and method for optimizing random access control, and for optimizing transmission efficiency of data packets over reverse common channels between access terminals and a base station, in a wireless communications system. In the communications system, at least one of the access terminals is adapted to transmit at least a portion of an access data packet to the base station, and the base station is adapted to receive the portion of the access data packet and, in response, to transmit a message for receipt by the plurality of access terminals which indicates receipt of the access data packet portion by the base station and identifies the access terminal from which said access data packet portion is received. The message can control the other access terminals to refrain from transmitting an access data packet, while indicating receipt of the access data packet portion to the certain access terminal from which the access data packet portion had been transmitted.

Abstract: An approach for performing congestion avoidance in a switching communication system is disclosed. An input port of the switching communication system receives a bandwidth request from a source. The switching communication system includes a bandwidth control processor that examines the bandwidth request, and multiple output ports. The output ports communicate with various destination sites. A congestion avoidance logic within the switching communication system generates multiple clusters based upon a transmission constraint associated with the output ports; each of the clusters corresponds to a portion of the destination sites. The congestion avoidance logic determines a cluster threshold that corresponds to traffic load distribution among the critical clusters. Additionally, the congestion avoidance logic selectively grants the bandwidth request based upon the determined cluster threshold.

Abstract: A payload design for a multi-spot-beam satellite communication system includes a plurality of uplink spot beam receivers and downlink spot beam transmitters, and a broadcast transmitting subsystem capable of transmitting a broadcast beam to an entire system geographical service area. An input filter-switch-matrix (IFSM) controllably selects input IF signal bands for routing to an on-board digital signal processor-router (DSPR). The DSPR subsequently routes all received point-to-point and broadcast data packets to the appropriate downlink spot or broadcast transmitting subsystems for transmission thereof. The broadcast downlink allows broadcast transmissions to occur at the highest efficiency possible, while also allowing for flexible provision of surge capacity for point-to-point transmissions on previously exhausted spot beams by selective use of the broadcast beam for such point-to-point transmissions.

Abstract: A method and system for generating single and multi-channel optical analog pulse-position modulation waveforms are disclosed. The system comprises a frequency modulator, a continuous wave optical source, and an optical modulator. The frequency modulator receives the analog signal and converts the analog signal into a frequency modulated signal. The optical modulator modulates the continuous wave optical source with the frequency modulated signal, to produce the optical pulse-position modulated signal. The method comprises converting an analog input signal into a frequency modulated signal amplifying the frequency modulated signal and producing a large signal therein, modulating a continuous wave optical source with the large signal, therein producing the optical pulse-position modulation signal, and compressing the optical pulse-position modulation signal, therein increasing a processing gain.

Abstract: A terrestrial communication system using satellite uplink and downlink frequencies is disclosed. A terrestrial cell site produces a signal at a satellite uplink frequency that is transmitted to a terrestrial user terminal. The terrestrial cell site receives a signal at a satellite downlink frequency that was transmitted by a terrestrial user terminal. The terrestrial cell site may include a signal nulling means in the direction of a satellite producing signals at the uplink and downlink frequencies.

Abstract: A system in which a personal computer sends messages into a TCP/IP network using a conventional dial-up link and downloads data from the TCP/IP network using a high-speed one-way satellite link. A preferred embodiment uses a conventional SLIP provider to connect to the TCP/IP network and uses a commercial software TCP/IP package that has a standard driver interface. A spoofing protocol compensates for the long propagation delays inherent to satellite communication.

Abstract: An approach is provided for bit labeling of a signal constellation. A transmitter generates encoded signals using, according to one embodiment, a structured parity check matrix of a Low Density Parity Check (LDPC) code. The transmitter includes an encoder for transforming an input message into a codeword represented by a plurality of set of bits. The transmitter includes logic for mapping non-sequentially (e.g., interleaving) one set of bits into a higher order constellation (Quadrature Phase Shift Keying (QPSK), 8-PSK, 16-APSK (Amplitude Phase Shift Keying), 32-APSK, etc.), wherein a symbol of the higher order constellation corresponding to the one set of bits is output based on the mapping.

Abstract: A signal processing circuit for satellite communications signal includes a first one dimensional digital beam forming circuit for forming a beam signal in a first direction and a second one dimensional digital beam forming circuit for forming a beam in a second direction. A direction filtering circuit is coupled between the first one dimensional digital beam forming circuit and the second one dimensional digital beam forming circuit. The filtering circuit determining a communications signal direction of the satellite communications signal and tunes the filter to reduce a filter bandwidth and a frequency range of said beam signal prior to processing through the second one dimensional digital beam forming circuit.

Abstract: A method of making a micro electromechanical switch or tunneling sensor. A cantilevered beam structure and a mating structure are defined on a first substrate or wafer; and at least one contact structure and a mating structure are defined on a second substrate or wafer, the mating structure on the second substrate or wafer being of a complementary shape to the mating structure on the first substrate or wafer. A bonding layer, preferably a eutectic bonding layer, is provided on at least one of the mating structures. The mating structure of the first substrate is moved into a confronting relationship with the mating structure of the second substrate or wafer. Pressure is applied between the two substrates so as to cause a bond to occur between the two mating structures at the bonding or eutectic layer. Then the first substrate or wafer is removed to free the cantilevered beam structure for movement relative to the second substrate or wafer.

Abstract: An electronic document delivery system and method in which a broadcast center periodically sends a “catalog” of available documents to a receiving computer, thereby allowing a user to browse through the available documents without having to access the broadcast center. The documents are transmitted as packets, and the packets are decrypted as soon as they are received, eliminating the need to store both an encrypted and an decrypted version of the documents at the receiving computer. The receiving computer periodically receives information allowing it to decrypt received documents and to encrypt billing information for the receiving computer. The invention is not limited to text-only documents and can receive all types of documents, such as software, images, text, and full-motion video.

Abstract: Electronic television program guide information is downloaded, stored and searched by a local device. A plurality of linked lists are used to remove redundancy, increase search speed, and allow dynamic categories. When a new category is encountered a new head node for a link list data structure is created. When a first program guide object containing information related to that category is downloaded, a link is made (i.e., a pointer is stored) from the head node to the guide object. When subsequent program guide objects containing information related to that category are downloaded, links are added to the end of the list or inserted in alphabetical order. As guide objects expire the links are removed. When no links remain in a particular category the head node for that category is deleted.