Abstract: A method includes transmitting a Domain Name Service (DNS) query from a user terminal; receiving the DNS query with at least one satellite in earth orbit; and applying the DNS query to a DNS server that is on-board the at least one satellite to obtain a corresponding Internet Protocol (IP) address. The method further operates, in the event the DNS server is unable to obtain the corresponding IP address, to transmit the DNS query to another DNS server, which may be located in another satellite, such as a higher altitude satellite, or to a terrestrial DNS server, such as one at a gateway or one reachable through the Internet. The method further operates to update the DNS server database that is on-board the satellite with information received from a terrestrial DNS server and/or from a space-based DNS server.

Abstract: A method is disclosed for operating a satellite telecommunications system, including transmitting a message from a user terminal, the message comprising a Uniform Resource Locator (URL); receiving the message with a satellite, selecting a gateway to receive the message based on the URL, and forwarding the message to the selected gateway; at the selected gateway, performing a Domain Name Service (DNS) query in response to the URL received in the message to obtain an Internet protocol (IP) address of a destination server identified by the URL; and replacing the URL with the IP address and sending the message from the gateway to the destination server having the IP address. The gateway is selected in response to a portion of the URL that identifies a country where the destination server identified by the URL is located, and the message is forwarded to the gateway that serves the identified country.

Abstract: Methods are provided for operating a mobile satellite telecommunications system, as is a system that operates in accordance with the methods. A first method has steps of providing at least one user terminal, at least one satellite in earth orbit and at least one gateway bidirectionally coupled to a data communications network and, responsive to applications, selecting with the user terminal individual ones of a plurality of Quality of Service (QoS) modes for servicing different application requirements. The method further includes communicating a request for a selected one of the QoS modes at least to the gateway. Another method operates in response to stored satellite ephemeris information for selecting a path through the satellite constellation to a destination gateway for routing a communication to or from the data communication network and the user terminal, and for transmitting a description of the selected path from the user terminal to at least one of the constellation of satellites.

Abstract: A method in accordance with this invention for operating a satellite communications system of a type that has a plurality of earth orbiting satellites, at least one terrestrial user terminal, and at least one terrestrial gateway, includes steps of determining a location and an azimuthal orientation of the user terminal; determining locations of one or more satellites co-visible to the user terminal and to the gateway; determining a signal quality of paths to each satellite co-visible with the gateway; displaying a representation to an operator of the user terminal, the representation depicting at least the orientation of the user terminal, the determined locations of the one or more satellites, and the determined signal qualities for satellites that are in use and those that are not in use; and changing the location of the user terminal in response to the displayed representation.

Abstract: A communications system (10) includes at least one satellite (105), at least one terrestrial gateway (103) capable of being bidirectionally coupled to the at least one satellite, at least one terrestrial paging system (109), and at least one user unit (106) capable of being wirelessly coupled to the terrestrial gateway, through the at least one satellite, or to the terrestrial paging system. The gateway includes a paging system (300) for receiving a page message for the user unit, for storing the received page message, and for selectively delivering the received page message to the user unit through the satellite system or through the terrestrial paging system. The gateway is bidirectionally coupled to the terrestrial paging system through the at least one satellite, a virtual gateway (107), and a pager interface unit (108).

Abstract: A method includes steps of establishing a wireless connection with a user terminal through a forward link and a return link; determining, during the connection, if an averaged transmitted power density associated with an antenna of the user terminal will equal or exceed, relative to a user of the terminal, at least one of a predetermined threshold level, within a specified unit of time, and an absolute threshold level; and taking action to reduce or eliminate the transmitted power at a time prior to or when the averaged transmitted power density level equals or exceeds the threshold level. The step of determining includes a step of considering the operation of the user terminal in a satellite communications system as well as in a terrestrial communications system.

Abstract: A method for operating a communication system includes providing a satellite communication system segment and a terrestrial communication segment, initiating a call from one user terminal to another user terminal, setting up the call using a ground station that is part of the satellite communication system segment and assigning satellite system resources to one of the user terminals that is designated a call manager for the call. The satellite communication system segment includes at least one satellite system ground station that is bidirectionally coupled to at least one satellite and the terrestrial communication segment includes a plurality of satellite user terminals located within a service region of the ground station.

Abstract: A satellite communication system (10) includes at least one satellite communication signal repeater (12); at least one ground station (18) for transmitting a feeder link comprised of a plurality of communication signals to the at least one satellite communication signal repeater; and a plurality of user terminals (13) each receiving one of the communication signals over a user link from the at least one satellite communication signal repeater. A method includes steps of measuring a quality of at least one reference signal received by the user terminal, via the satellite; transmitting the measured quality of the reference signal received by the user terminal to the ground station; comparing the measured quality with a predetermined reference; and adjusting a transmit power of the ground station in response to a difference between the predetermined reference and measured quality.

Abstract: A communications system includes a satellite communications component having at least one satellite and at least one terrestrial gateway, and also a wireless terrestrial communications component having at least one-repeater and at least one mobile switching center. The at least one gateway and the at least one mobile switching center are coupled together by a first mobile applications part (MAP) network, such as an IS-41 or GSM MAP network. The at least one gateway and the at least one mobile switching center are further coupled to a terrestrial communications network (PSTN).

Abstract: A communications system includes at least one low earth orbit first satellite (10), at least one second satellite (11) in other than a low earth orbit, and a ground segment (12) that includes a plurality of user transceivers (78, 80, 82, 84) and at least one gateway (76) coupled to a publicly-accessible terrestrial communications system, such as a PSTN and/or a fiber optic network. The first satellite includes a first transceiver for communication with the at least one gateway, a second transceiver for communication with at least one user transceiver, and a third transceiver for communication with the at least one second satellite. The first, second and third transceivers are switchably coupled together on-board the first satellite by on-board processors, and a switching matrix for relaying a user communication between the at least one gateway and the at least one user transceiver via the at least one second satellite.

Abstract: A method and system wherein a system gateway (18) determines, from closed loop power control information, a power density at an antenna (13a) of a user terminal 13. The gateway also maintains a record of a duration of time that the power density exceeds a specified threshold. The gateway determines if an averaged transmitted power density associated with the antenna of the user terminal will equal or exceed at least one of a predetermined threshold level, within a specified period of time, or an absolute threshold level. If the gateway determines that a threshold will probably be exceeded if the call connection is maintained, the gateway terminates the connection prior to a time that the user terminal averaged transmitted power density level equals or exceeds the predetermined or absolute threshold level. A tone or a visual indicator may be employed to warn the user that a current connection or call will be terminated. Provisions are made for allowing predetermined types of calls (e.g.

Abstract: A communications system (10) includes at least one satellite (105), at least one terrestrial gateway (103) capable of being bidirectionally coupled to the at least one satellite, at least one terrestrial paging system (109), and at least one user unit (106) capable of being wirelessly coupled to the terrestrial gateway, through the at least one satellite, or to the terrestrial paging system. The gateway includes a paging system (300) for receiving a page message for the user unit, for storing the received page message, and for selectively delivering the received page message to the user unit through the satellite system or through the terrestrial paging system. The gateway is bidirectionally coupled to the terrestrial paging system through the at least one satellite, a virtual gateway (107), and a pager interface unit (108).

Abstract: A method is for defining a radio frequency map to be used to isolate negative effects of undesirable radio frequency emitters on radio device communications, handheld and stationary. The method includes the steps of measuring C-band power corresponding to an L-band beam as part of an L-band footprint of a communication satellite, calculating various identifiable interference errors associated with the signal transmission path, and subtracting the interference errors from the original C-band power measurement resulting in a power value corresponding to undesirable radio frequency emitter interference at the location of the L-band beam. The resultant radio frequency map can then be used to reallocate frequency channels of operation used by radio devices, mobile phones for example, resulting in power savings in the radio device while maintaining a suitable signal-to-noise ratio.

Abstract: A satellite communication system (10) includes at least one satellite communication signal repeater (12); at least one ground station (18) for transmitting a feeder link comprised of a plurality of communication signals to the at least one satellite communication signal repeater; and a plurality of user terminals (13) each receiving one of the communication signals over a user link from the at least one satellite communication signal repeater. The satellite communication system further includes a closed loop power control system (80) having a plurality of inner loops (84), individual ones of which operate to compensate one of the user links for communication signal impairments occurring at least between the user terminal and the at least one satellite communication repeater, and an outer loop (82) which operates to compensate all of the user links for feeder link impairments occurring between the at least one ground station and the at least one satellite communication signal repeater.

Abstract: A system and method for controlling the transmission power of a user terminal in a satellite communications system of a type that includes a ground segment, comprised of at least one user terminal and at least one terrestrial gateway, and a space segment, comprised of a plurality of satellites in a non-geosynchronous earth orbit. The method includes the steps of (a) transmitting an uplink signal from the user terminal simultaneously to at least two satellites of the space segment and (b) receiving the uplink signal with each of the at least two satellites.

Abstract: A communications system includes a satellite communications component having at least one satellite and at least one terrestrial gateway, and also a wireless terrestrial communications component having at least one repeater and at least one mobile switching center. The at least one gateway and the at least one mobile switching center are coupled together by a first mobile applications part (MAP) network, such as an IS-41 or GSM MAP network. The at least one gateway and the at least one mobile switching center are further coupled to a terrestrial communications network (PSTN).

Abstract: A satellite communications system (10) includes at least one satellite (12); a system controller (38); a plurality of gateways (18); and at least one user terminal (13) operable for bidirectionally communicating with at least one of the gateways through the at least one satellite. Individual ones of the plurality of gateways are bidirectionally coupled to at least one terrestrial communications system (4) and act to couple the user terminal to the terrestrial communication system through at least one satellite. In accordance with an aspect of this invention, individual ones of the plurality of gateways are operable for receiving an access request from the user terminal, through at least one satellite, and are further operable for notifying the requesting user terminal, through at least one satellite, that the user terminal is one of accepted by the gateway for establishing a communication link and not accepted by the gateway for establishing the communication link.

Abstract: A method for operating a satellite communications terminal (10) that transmits one of digital voice or data signals during a frame period. The terminal includes a transmitter and a receiver, the transmitter including an RF power amplifier.

Abstract: A method is disclosed for operating a first satellite communications system of a type that operates co-frequency with at least one second transmission system, such as a second satellite communications system. The method includes steps, executed during the operation of the first satellite communications system, of measuring at a plurality of locations within a coverage area of the first system an amount of interference resulting at least in part from the at least one second transmission system, the amount of interference being measured over a band of frequencies allocated to the first system; (b) transmitting an indication of the measured interference from each location to a central site; and (c) in accordance with the transmitted indications, assigning at least one user terminal to a sub-band of frequencies within the band of frequencies so as to reduce an amount of interference experienced by the user terminal.

Abstract: A method and system for accurately accounting for an amount of satellite communications system resources that are allotted to and utilized by a user terminal on a per call or connection basis. The method accumulates data at periodic intervals during a connection, the data indicating what portion of the overall system resources are utilized on both a forward link (gateway to satellite(s) to user terminal) and on a reverse link (user terminal to satellite(s) to gateway). The usage data can include power levels, data rates, user terminal location, and user terminal type. A Gateway (18) that is assigned to handling the call for the user terminal (13) accumulates the data and subsequently transfers the data over a terrestrial data network (39) to a Ground Operations Control Center (38). The center uses the data to determine an amount to be billed to a service provider associated with a service area that includes the gateway.