Abstract: A system and method of operation for efficiently reusing and/or sharing at least a portion of the frequency spectrum between a first satellite spot beam and a second satellite spot beam, and/or an underlay terrestrial network associated with a second satellite spot beam. The spectrum is efficiently reused and/or shared between respective spot beams and/or associated underlay terrestrial systems in a manner minimizes interference between the respective satellite and terrestrial systems.

Abstract: Chronologically synchronizing a unique positing signal generated by a positioning-unit device at a known location with a reference positioning signal generated by a reference transmitter at a known geometric distance. The positioning-unit device receives and interprets a reference positioning signal. It then generates and transmits a unique positioning signal, wherein the unique positioning signal is aligned with a frequency steerable clock. The positioning-unit device then receives the unique positioning signal. The positioning-unit device then adjusts the frequency of the frequency steerable clock by an amount derived from a measured frequency difference. The positioning-unit device then determines a reference positioning signal propagation delay between the reference transmitter and the positioning-unit device. At this stage, a time difference is measured between the received reference positioning signal and the received unique positioning signal.

Abstract: A method for allocating transmission channels to devices configured to communicate short data packets to a diversity of non geostationary satellites is disclosed hereby. The method suggests a dynamic cellular partitioning of the earth surface, based on the smallest intersections of overlapping satellite service areas (“footprints”), defined as mega-cells, and reusing channels in different mega-cells. In addition, a transmission cycle is defined and divided to time slots, synchronized at each device by GPS timing signals, and mega-cells served by more satellites are allocated with fewer time slots, in order to increase the chance of transmitters placed in mega-cells served by fewer satellites to be detected. Further, each mega-cell is divided to cells, and different channels and time slots are allocated to each cell, from those allocated to the corresponding mega-cell.

Abstract: A satellite radiotelephone system includes a space-based component that is configured to receive wireless communications from radiotelephones over a range of satellite band return link frequencies and to transmit wireless communications to radiotelephones over a range of satellite band forward link frequencies. An ancillary terrestrial component is configured to receive wireless communications from radiotelephones over the range of satellite band return link frequencies, and to transmit wireless communications to radiotelephones over the range of satellite band forward link frequencies.

Abstract: DVB-S/S2 transmodulator for VSAT units employing IP based communication. The transmodulator is optimized for VSAT networks, enabling legacy VSAT units to benefit from the developments of the advanced DVB-S2 standard. The transmodulator appears transparent to the legacy VSAT unit that is configured to operate with the older DVB-S standard. Some embodiments offer a unique feedback channel allowing the transmodulator to send messages and information to the ground station via the VSAT itself.

Abstract: A wireless communications system includes a space-based component (SBC) and an ancillary terrestrial component (ATC) configured to communicate with radioterminals using a common satellite service link frequency band and respective first and second different sets of channel separation codes. The first and second sets of channel separation codes may include, for example, respective sets of scrambling codes, respective sets of frequency assignment codes, respective sets of channel assignment codes, respective sets of sub-channel assignment codes and/or respective sets of spreading codes.

Abstract: A method and system for determining delays between a primary site and a diverse site in a satellite communication system includes uplinking signal from the primary site and the diverse site. A controller determines a switchover processing time, a communication time between the primary site and the diverse site and a gap time to establish a gap at the receiving device. The controller changes uplinking from the primary site to the diverse site in response to the switchover processing time, the communication time and the gap time.

Abstract: A system and method of operation for efficiently reusing and/or sharing at least a portion of the frequency spectrum between a first satellite spot beam and a second satellite spot beam, and/or an underlay terrestrial network associated with a second satellite spot beam. The spectrum is efficiently reused and/or shared between respective spot beams and/or associated underlay terrestrial systems in a manner minimizes interference between the respective satellite and terrestrial systems.

Abstract: A space-based component, such as a satellite, is configured to receive wireless communications from radiotelephones in a satellite footprint over an uplink satellite radiotelephone frequency, and to transmit wireless communications to the radiotelephones over a downlink radiotelephone frequency. An ancillary terrestrial network, that may include one or more ancillary terrestrial components, is configured to transmit wireless communications to, and receive wireless communications from, the radiotelephones over the downlink satellite radiotelephone frequency in a time-division duplex mode. By terrestrially transmitting and receiving wireless communications over the downlink satellite radiotelephone frequency in a time-division duplex mode, interference at the space-based component and/or at the gateway, by the ancillary terrestrial network and/or the radiotelephones due to terrestrial reuse of cellular satellite frequency spectrum, may be reduced or eliminated.

Abstract: A method for establishing radiofrequency links via a telecommunication satellite having several spots, designated a multispot satellite, between at least one terrestrial station and a service area composed of a plurality of elementary covering zones, designated cells, each cell comprising a plurality of terrestrial terminals is disclosed. This type of satellite allows the use of several spots of antennae on board the satellite to cover contiguous geographical zones or cells, instead of a single broad spot. Each cell is associated with a spot to which a frequency band is attributed. In the case of the loss of a spot associated with a cell, designated a faulty cell, the spot (FR1, FR2, FB1, FB2, FV1, FV2) associated with at least one contiguous cell (CR1, CR2, CB1, CB2, CV1, CV2) to the said faulty cell is likewise associated with a part of the said faulty cell so that the area (CPJ?) of said faulty cell is reduced.

Abstract: Information content is nonidentically mapped between service link carriers and feeder link carriers at a cellular satellite. A reduced number of satellite feeder link carriers compared to the number of satellite service link carriers and/or a reduced total bandwidth of the satellite feeder link carriers compared to the satellite service link carriers thereby may be obtained.

Abstract: Techniques and systems for designing a network providing communication and location identification services are described. A solution point comprising parameters for each of a plurality of base stations is generated. A coverage and locatability performance value for the solution point is computed, as well as derivatives of the performance value. The coverage and locatability performance value and its derivatives are used to indicate favorable directions for searching for subsequent solution points, and subsequent solution points are generated and compared against previous solution points until an optimum solution point is found. The coverage and locatability performance value is a weighted sum of coverage and locatability values for each point in the service area of the network, with coverage values representing forward and reverse link quality and locatability values representing the probability that a point will experience an acceptable power level from at least four base stations.

Abstract: A wireless communication device receives CDMA signals and communicates with remote base stations in site selection diversity transmit (SSDT) mode. During communications with a primary base station, communication state parameters, such as signal to interference ratio (SIR) target values and carrier frequency estimates, are maintained for other base stations of an active set of base stations. The state parameters for communications with a selected base station are available for use after selection of a new base station. In one embodiment, the communication state parameters are used for the selection of a base from the active set.

Abstract: A communication system has a plurality of ground stations and a plurality of satellites located in a first orbit with respect to the earth. The satellites generate a plurality of beams corresponding to a respective plurality of cell. The plurality of beams has widths that vary relative to position in the orbit to maintain a cell size of the plurality of cells. A plurality of user terminals within the cells receives communication signals from the satellite.

Abstract: A method for re-selecting control channels in a mobile station reduces the use of resources by limiting an evaluation of candidate control channels to those channels which satisfy certain criteria and are deemed to be eligible control channels. As a consequence, resources are not spent on attempting to re-select a control channel that is not compatible with the mobile station.

Abstract: A power gated variable hop cycle beam laydown (700) manifests itself as first cells (C, D) supported by a first hop cycle, second cells (G, H) supported by a second hop cycle, and transition cells (E, F) supported by a transition hop cycle. The transition hop cycle uses power gating to transition the laydown (700) from cells (C, D) operating at the first hop cycle to cells (G, H) operating at the second hop cycle. To this end, the transition hop cycle power gates its downlink beam for a portion of time needed to reduce interference between nearby (e.g., adjacent) cells.

Abstract: Systems and methods are disclosed for feeder link configurations to layered modulation. One feeder link system employs feeder link spot beam to antennas in distinct coverage areas to enable frequency reuse. Another system employs narrow beam width feeder link antenna to illuminate individual satellites also enabling frequency reuse. Yet another system uses layered modulation in the feeder link. Another feeder link system employs a higher order synchronous modulation for the satellite feeder link than is used in the layered modulation downlink signals.

Abstract: A communication system has a high altitude communication device that has an antenna for directing beams to a fixed cell pattern with a polarity of cells. A specific pattern of cells having the same communication resource is provided. Preferably, cells having the same resource are separated. The antenna is shaped to suppress interference with locations having the same resource. The areas not having the same resource are not suppressed to allow the system to have maximum capacity and allow a smaller antenna aperture.

Abstract: A radio signal relay device such as satellite is used to cover several relatively small geographical regions with relatively narrow beams as well as a relatively large geographical region with a single beam. This relatively wide beam permits legacy equipment to be used. A transmitting device in a beam transmits a signal to the relay device, which in turn retransmits the signal to a receiving device. The transmitting devices, relay device, and receiving devices synchronize communication by using a particular mode of communication which includes a band of carrier frequencies and a protocol. In addition to communicating like mode signals from a transmitter to a receiver, the relay device may be used in a dual mode communication system to translate signals from the one mode to another. A translator may direct a transmitter to modulate a signal on a different carrier frequency, convert one protocol into another protocol, or both.

Abstract: The invention relates to a method and a system for harmonising an operational area for a mobile device on a cell-by-cell-basis in a cellular radio network, like a GSM network, wherein, in idle mode, the mobile device compares field strength levels of different base stations with each other in order to set up a power budget, and selects the most appropriate base station in accordance with said power budget, wherein for prioritizing a predetermined base station an individual additional offset term is applied in the power budget. The invention is characterized in that in connection mode, the mobile device compares the power received from different base stations with each other in order to set up a power budget, and selects the most appropriate base station in accordance with said power budget, wherein for prioritizing a predetermined base station an individual additional offset term is applied in the power budget, and both offset terms are set so as to be similar to each other or the same.

Abstract: A communication system has a stratospheric platform with a payload controller and a phased array antenna having a plurality of main array elements for generating a plurality of communication beams and a plurality of auxiliary elements for canceling interference between the communication beam. A gateway station communicates with the stratospheric platform. The gateway station scales the plurality of elements to form a reconfigurable plurality of beams. The gateway station communicates an embedded control signal to the stratospheric platform to communicate a scaling of elements to form the communication beams and the auxiliary element output. The auxiliary element output is used to provide interference canceling.

Abstract: A system and method is described here for discovering capabilities of nearby telephones using a secondary communication channel. The secondary communication channel can use various media that can include infrared, Bluetooth, Wi-Fi 802.11 a/b/g, or any other medium that is not used for the purpose of primary telephone communication. Usage of the secondary channel isolates this feature from the state of the art system and at the same time provides for a common method of interoperability for various telephones. Infrared communication for the secondary channel is preferred, due to its cost, and easy of usage.

Abstract: A mobile station (4) in a satellite mobile telephone system predicts when it will move into another cell on the basis of one set of broadcast information thereby reducing the overall processing burden. The mobile station (4) can predict with a useful degree of certainty which broadcast control channel (BCCH) frequencies it should listen on when it wakes up on the basis of a stored map of the relative positions of cells. The broadcast information includes information about the current cell's (40) shape (V1, V2, V3, V4, V5, V6) and translational (T) and rotational (R) motion.

Abstract: A method and apparatus for redistributing power radiated by an antenna comprised of a plurality of antenna elements. An antenna directivity estimator function is performed to screen out inappropriate antenna directivity profiles from a plurality of antenna directivity profiles, thereby determining one or more remaining, appropriate antenna directivity profiles. An optimizer function is performed on the remaining, appropriate antenna element directivities to determine a phase distribution for the antenna elements based on a desired power distribution for the antenna.

Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.

Abstract: A mobile wireless communications system including a plurality of individual transponding nodes of various types, all in communication with a central processing hub. A local user signal is processed by the central processing hub and radiated through multiple paths to a plurality of the plurality of individual transponding platforms simultaneously. The signal is then re-radiated by each of the plurality of the plurality of individual transponding platforms to a mobile terminal that receives the re-radiated signal from the plurality of the plurality of individual transponding platforms coherently and in phase. The number of transponders and codes used to transmit each user signal can be readily adapted to user requirements. Additionally, each user is assigned a profit value by the central processing hub depending upon certain user characteristics. The assigned user profit value allows the total system utility/profitability to be maximized.

Abstract: A communications system includes an antenna that produces a series of beams which divide a service region into a plurality of contiguous cells, and dynamically modifies cell boundaries so that the system's allocated communication spectrum is efficiently utilized.

Abstract: A communication system has a plurality of ground stations for communicating communication signal to a plurality of satellites located in an inclined elliptical sub-geosynchronous orbit with respect to the earth. The plurality of satellites operate in a service area in a synchronized manner to provide continuous coverage to the service area. The satellites generate a plurality of beams with variable beamwidths to obtain a substantially uniform cell size covering the service area. A user terminal within the service area receives communication signals from the satellite.

Abstract: A wireless communication system includes multiple wireless communication platforms carrying reflectors for providing spot beams. By using multiple platforms, the payload can be split. Each platform carries only a part of the reflectors needed to provide coverage for a certain geographic area. That allows the reflectors to be of larger size providing smaller spot beams. The multiple platforms of the wireless communication system are designed to be interchangeable. Therefore, only one standby platform is necessary for backup. By further providing an closed-loop pointing control method it is possible to keep multiple platforms pointed accurately relative to each other and relative to the user coverage area.

Abstract: A mobile satellite telecommunications system is disclosed comprising at least a user terminal and a satellite which is in earth orbit and at least a gateway bidirectionally coupled to a data communications network. The user terminal comprises a controller responsive to at least one criterion having been met for activating an indicator to inform a user of a potential for reduced user terminal performance.

Abstract: A method and system is for automatically updating a home-zone list in a subscriber database as the configuration of a cell changes in a cellular mobile telecommunication system mounted with a home-zone service center. Specifically, the method includes the steps of deciding at least one base station having a base station system parameter according to a change in the cell configuration because of expansion, moving or dismantlement of a base station, selecting at least one subscriber who is under the influence of changes in the base station, generating a home-zone list including at least one home-zone base station that can provide a home-zone service to every selected subscriber, and updating a database of the subscriber based on the generated home-zone list.

Abstract: A dual-band multiple beam antenna system for a communications satellite sharing a set of reflector antennas for the transmit and receive frequencies. One set of reflectors is common to both the downlink and uplink frequencies. The feed horns are diplexed and exhibit frequency-dependent radiation patterns that separate the phase centers over the downlink and uplink frequency bands to obtain dual-band performance. The focal point of the reflector is in close proximity to the phase center corresponding to the downlink frequency band. The phase center for the uplink frequency band is spaced a predetermined distance from the phase center of the downlink frequency band. According to the present invention, the uplink frequencies are defocused and the downlink frequencies are focused thereby creating identical radiation patterns at both frequency bands and over the coverage region of the communications satellite.

Abstract: Techniques and systems for designing a network providing communication and location identification services are described. A solution point comprising parameters for each of a plurality of base stations is generated. A coverage and locatability performance value for the solution point is computed, as well as derivatives of the performance value. The coverage and locatability performance value and its derivatives are used to indicate favorable directions for searching for subsequent solution points, and subsequent solution points are generated and compared against previous solution points until an optimum solution point is found. The coverage and locatability performance value is a weighted sum of coverage and locatability values for each point in the service area of the network, with coverage values representing forward and reverse link quality and locatability values representing the probability that a point will experience an acceptable power level from at least four base stations.

Abstract: A method and apparatus for transmitting data to a plurality of users, each individual user disposed in one of a plurality of cells is disclosed. One embodiment of the method comprises the steps of defining a first set of receivers from at least a portion of the plurality of receivers according to a first desired power level range, defining a first group of receivers from the first set of receivers according to a first spatial isolation constraint, defining a second set of receivers from a remaining plurality of receivers not a member of the first set of receivers according to a second desired power level range, defining a second groups of receivers from the second set according to a second spatial isolation constraint, and assigning a first transmission channel to the first group and a second transmission channel to the second group.

Abstract: A state transition diagram is presented for a user's access terminal for a satellite telecommunication system, showing the state of the access terminal's mobility management software layer, in response to various stimuli and conditions as the user enters into and out of various modes of operations, including deactivation, activation and illumination of a dark beam of a spot beam that is a shared resource.

Abstract: A telecommunications network simplifies data flow and signaling by having a second control node (262) of a radio access network transmit cell information to a first control node (261) only when the cell information is not already known by the first control node. The invention is facilitated by a cell configuration generation index (CCGI). The cell configuration generation index (CCGI) represents a set of cell information parameters deemed current for a specified cell by a control node. In one example embodiment, the cell configuration generation index (CCGI)is a counter whose value is changed when configuration data of the specified cell is changed. In one example scenario, a cell identifier for the specified cell and the first control node's CCGI for the specified cell are included in a request message sent from the first control node to the second control node.

Abstract: A cellular network configuration tool is described that performs frequency assignments for use in a cellular network. The channels are assigned in accordance with input configuration data such as a channel separation matrix, geographic data, and requested channel assignments for each sector included in the cellular network being configured. The configuration is performed in accordance with predetermined constraints and criteria and quality of service input. The tool uses frequency assignment techniques to perform the channel assignments in accordance with varying constraints and criteria.

Abstract: An object of the invention is to make improvement in the configuration of location registration areas. When a base station 13P is newly installed in a location registration area 30A, the base station 13P recognizes a location of its own with GPS or the like and performs communication with a plurality of surrounding base stations 13Q to select a location registration area 30A to which it should belong, based on the belonging status of the surrounding base stations 13Q and the location of its own.

Abstract: A satellite-based communications system operating at high data rates includes a plurality of satellites each having uplink and downlink antennas for transmitting and receiving a plurality of signals utilizing a plurality of spot beams to and from a plurality of coverage areas at a predetermined range of frequencies. The system can include, or be combined with, other systems to enable increased capacity over high population areas and ubiquitous coverage over lower population areas. A portable antenna assembly can be coupled to a user's portable or mobile electronic device for coupling the electronic device directly to a satellite. A routing switch provides routing and switching on-board the satellite and routes signals according to their desired destination.

Abstract: This disclosure describes a method to generate large numbers of spot beams for multiple-beam satellite systems using smaller apertures. This is done by dividing the basic spot beam that has 3 to 4 dB of gain drop within the beam into a number of smaller 1-dB sub-beams. This has the effect of reducing the required peak gain for the antenna by 2–3 dB, thus reducing its size by as much as 50%. The frequency band allocated to the basic beam will be divided among the sub-beams. However, the frequency re-use among the basic beams can be maintained. Frequency allocations have to be coordinated among all beams. This concept is especially applicable to phased arrays using digital beam formers. The DBF complexity is a function of the number of array elements, and is less dependent on the number of beams. Reducing the array size, and consequently reducing the number of elements helps in reducing the complexity, power and mass of the DBF.

Abstract: A space-based network for a satellite radiotelephone system includes at least one receive-only satellite and at least one transmit satellite. The transmit satellite can be a transmit-only satellite or a transmit and receive satellite. The receive-only satellite(s) are configured to receive wireless communications from a radiotelephone at a location over a satellite frequency band. The transmit satellite(s) are configured to transmit wireless communications to the radiotelephone at the location over the satellite frequency band. By providing at least one receive-only satellite and at least one transmit satellite, space-based networks can offer a significant link margin, without the need to undesirably burden the radiotelephones themselves to achieve this link margin.

Abstract: A self-configuring wireless system and a method are disclosed. The method derives re-use criteria and neighbor lists to enable the assignment of channels to cells in a wireless communications system, based entirely on measurements made by the system during normal operation. The disclosed method can be implemented with conventional cellular equipment and functionality provided by current air interface standards, and requires no human participation. The disclosed method also applies to the derivation of neighbor lists.

Abstract: A method and apparatus are provided for supporting the transmission of communications data in a satellite communications network 10 between user terminals 15–18 and a ground station 14 via a satellite 12. At least one carrier signal is generated in a beam spot and conveys communications data over at least one downlink 22–25 to the user terminals 15–18. The carrier signal is modulated simultaneously with independent communications data streams EDP15 and EDP 18 over modulation channels 802 and 804, respectively, of a multi-dimensional modulator 400. By passing independent data streams over each dimension of an n-dimension modulation technique, different encoding schemes may be assigned to user terminals 15–18 based upon the strength of the signal received by the user terminal 15–18.

Abstract: A multi-beam satellite comprises an input section receiving a plurality of first spot beams and an output section transmitting a plurality of second spot beams. A payload architecture is coupled between the input section and output section. It flexibly and selectively switches and filters the first plurality of spot beams received by the input section and provides signals to the output section to be transmitted as the second plurality of spot beams.

Abstract: A mobile communication system has a plurality of satellites and mobile stations. A mobile station is capable of communicating with more than one satellite. A satellite transmits a set of neighboring cell data to one of the mobile stations. The data set comprises first and second portions related to communication with a first and a second satellite of the plurality of satellites, respectively. When the data set is received the first time by the mobile station, it decodes both first and second data portions to establish a neighboring cell list, which is stored within the mobile station. When the mobile station receives subsequent transmissions of neighboring cell data, it need only decode either the first data portion or the second data portion based on the presence or absence of an alert message.

Abstract: This disclosure provides a communications system using a span-loaded flying wing, traveling at relatively slow speeds, that can remain airborne for long periods of time. The communications system uses the airplane as a long term high altitude platform that can serve at lest one of a number of potential functions. One function is to link to a ground station using radio wave signals and a satellite using optical signals. Another function is to serve as a relay station between ground communication nodes and individual end-users. Because the aircraft can tightly hold a station, the end-user's antennas do not need to be continuously adjustable. For such a system, a large number of aircraft can be used, with the end-user antennas being configured for a narrow beamwidth so as to allow frequency reuse for different communication links.

Abstract: Information content is nonidentically mapped between service link carriers and feeder link carriers at a cellular satellite. A reduced number of satellite feeder link carriers compared to the number of satellite service link carriers and/or a reduced total bandwidth of the satellite feeder link carriers compared to the satellite service link carriers thereby may be obtained.

Abstract: A method, system, and computer program product for dynamically adjusting the encryption level based on the geographic location of a software program are disclosed. The method includes an initial step of determining a geographic location associated with the software program. An encryption level is selected based upon the determined geographic location. The software program is then executed utilizing the selected encryption level. In one embodiment, determining the geographic location is achieved by determining the geographic location of a computer system on which the software program will be executed, preferably through the use of a Global Positioning System. The Global Positioning System may comprise an I/O device of the computer system on which the software executes. In one embodiment, the selected encryption level may be overridden by a Smart Card or other secure device connected to the computer system. In one embodiment, the available encryption levels include, at a minimum, a U.S.

Abstract: A system has a stratospheric platform with a payload controller and a phased array antenna having a plurality of elements. A gateway station communicates with the stratospheric platform. The gateway station scales the plurality of elements to form a reconfigurable plurality of beams. The gateway station communicates a control signal to the stratospheric platform to communicate a scaling of the elements. The stratospheric platform configures the elements of the phased array antenna according to the scaling using adaptive interference rejection. The gateway station has an adaptive beam processor coupled to user position files. The adaptive beam processor with the user position data can adaptively cancel interference from other beams.

Abstract: A system and method of operation for efficiently reusing and/or sharing at least a portion of the frequency spectrum between a first satellite spot beam and a second satellite spot beam, and/or an underlay terrestrial network associated with a second satellite spot beam. The spectrum is efficiently reused and/or shared between respective spot beams and/or associated underlay terrestrial systems in a manner minimizes interference between the respective satellite and terrestrial systems.