Abstract: An air to ground communication system provides internet access to aircraft from ground based stations. The air to ground system shares spectrum with uplink portions of a satellite communication spectrum. Interference mitigation techniques are employed to avoid interference between the ground based communications and satellite communications. Fade mitigation techniques are employed to provide communication to aircraft at low angles of elevation in the presence of rain.

Abstract: A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.

Abstract: A method for air to ground communication interference mitigation within an aircraft equipped with a multi-beam array antenna includes adjusting a modulation symbol interleaving and/or forward error correction of an aircraft receiver interface in response to detected interference from an interferer. The method further includes reducing a data rate of the aircraft receiver interface when the adjusting of the modulation symbol interleaving and/or forward error correction does not mitigate the detected interference. Another method for interference mitigation may include performing antenna beam-steering away from a geographic (GEO) arc during an aircraft turn. This method further includes reducing an aircraft transmitter transmit power when a signal quality of a forward link is within a predetermined range of a signal quality threshold.

Abstract: A method for real-time calibration of an air to ground two-way communication system. The method includes calibrating a ground base station antenna array according to forward link calibration coefficients received from an aircraft as part of a communication signaling protocol during operation of the air to ground two-way communication system. The method may also includes communicating between the ground base station antenna array and the aircraft over a narrow beam.

Abstract: Aspects describe utilizing the Internet capability in mobile devices/networks to deliver broadcast multimedia to a device. The broadcast can be video, audio, and so forth. Initially the broadcast multimedia is transmitted at high data rates (and in unicast mode) in order for a buffer associated with mobile device to be built to a very long buffer length. When the long buffer length is reached, the multimedia can be delivered at real-time rates. The multimedia delivered at real times rates can be unicast mode or in multicast mode. If the buffer is depleted, a mobile device that is part of a multicast group can autonomously disassociated from the group until the buffer length is restored.

Abstract: A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.

Abstract: A satellite communication system for providing communications between user terminals and gateways constituted with m primary satellites. In one embodiment, n back up satellites are also provided. Further, each satellite, primary or back-up, is equipped to project N/m beams onto and across an area in a loosely-packed array manner. M of the m primary and n back-up satellites collectively create N beam spots to cover the area. Moreover, each sub-area is covered by a beam spot separated from another sub-area covered by another beam spot by one beam width. Each satellite is also equipped to facilitate communication over 1 of m band of frequencies on one beam. AS a result, any of the m primary satellites may be efficiently replaced on demand by a selected one of the n back-up satellites. The gateways and user terminals are configured to communicate signals through or with both or either the primary and back-up satellites.

Abstract: A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.

Abstract: A method for air to ground communication interference mitigation within an aircraft equipped with a multi-beam array antenna includes adjusting a modulation symbol interleaving and/or forward error correction of an aircraft receiver interface in response to detected interference from an interferer. The method further includes reducing a data rate of the aircraft receiver interface when the adjusting of the modulation symbol interleaving and/or forward error correction does not mitigate the detected interference. Another method for interference mitigation may include performing antenna beam-steering away from a geographic (GEO) arc during an aircraft turn. This method further includes reducing an aircraft transmitter transmit power when a signal quality of a forward link is within a predetermined range of a signal quality threshold.

Abstract: An air to ground communication system provides internet access to aircraft from ground based stations. The air to ground system shares spectrum with uplink portions of a satellite communication spectrum. Interference mitigation techniques are employed to avoid interference between the ground based communications and satellite communications. Fade mitigation techniques are employed to provide communication to aircraft at low angles of elevation in the presence of rain.

Abstract: A satellite includes a programmable facility including circuitry responsive to programmable control information. One or more filter parameters, or other forms of instructions for allocating channel capacity (i.e. bits/second/Hz), are received at the satellite in orbit to direct the programmable facility to separate particular sub-signals from an input signal. In one embodiment, the programmable facility can be programmed to change the allocation of channel capacity dedicated to the forward and return links based on the ratio forward and return traffic through a satellite. Changing the allocation of channel capacity may be achieved by changing the portions of the total allocated frequency bandwidth that are used for forward and return links. Alternatively, the changes may be made to the forward and/or return data rates, either alone or in combination with frequency bandwidth allocations.

Abstract: Synchronization of satellite and terrestrial broadcasts in a shared frequency arrangement is use in order to facilitate simultaneous reception of the broadcasts. A delay value is adjusted based on a synchronization between a first terrestrial broadcast and a satellite broadcast, and a delay value for a second terrestrial broadcast is adjusted based on a synchronization between the second terrestrial broadcast, the first terrestrial broadcast and the satellite broadcast. The adjustment of the relative delay values provides an improved reception pattern based on receipt of a shared frequency communication from multiple sources by improving a signal quality factor within at least selected regions of the coverage areas in which the relative delay values permit synchronization.

Abstract: A method for real-time calibration of an air to ground two-way communication system. The method includes calibrating a ground base station antenna array according to forward link calibration coefficients received from an aircraft as part of a communication signaling protocol during operation of the air to ground two-way communication system. The method may also includes communicating between the ground base station antenna array and the aircraft over a narrow beam.

Abstract: A ground station antenna array includes a first array of antenna elements. A second array of antenna elements are vertically aligned with the first array of antenna elements. The first array of antenna elements and the second array of antenna elements are coupled to the digital beam forming circuitry and each cover a same sector of azimuth; the first array of antenna elements only covering a first elevation; the second array of antenna elements only covering a second lower elevation. The digital beam forming circuitry directs a radiation pattern of the first array of antenna elements in a first range of elevation angles, and directs a radiation pattern of the second array of antenna elements in a second range of elevation angles. The second array of antenna elements has higher gain than the first array. A respective transceiver is coupled to respective antenna elements of the first and second arrays.

Abstract: A method for ground to air communication includes receiving a first pilot signal on a first wide beam from a first ground base station by a first antenna element covering a first range of azimuth angles from an aircraft. Data is received on a directed data beam from the first ground base station by the first antenna element. A second pilot signal is received on a second wide beam from a second ground base station by a second antenna element covering a second range of azimuth angles different than the first range of azimuth angles. A signal strength of the second pilot signal is compared with a signal strength of the first pilot signal. Data reception is switched from the first antenna element to the second antenna element if the signal strength of the second pilot signal is greater than the signal strength of the first pilot signal.

Abstract: A quality measure, such as a signal-to-noise ratio, of a signal arriving at a gateway for a return link is used to adjust a data rate for the link. The return link is transferred from a terminal to the gateway through a satellite, and shared by a number of user terminals at any given time, including the terminal for which the data rate is adjusted. The terminals sharing the link have a certain interference relationship. Adjusting a data rate for a message sent from one or more terminals through the return link in the presence of signal degradation or power loss does not appreciably change the interference relationship among the plurality of terminals.

Abstract: Communication diversity using a plurality of satellites is disclosed. The satellites can support multiple regions corresponding to multiple satellite beams. Each satellite can support all regions in the reverse direction and each satellite can be designated as a primary satellite for one of the multiple regions corresponding to one of the multiple satellite beams. Each satellite can receive from any of the regions reverse link signals broadcast by, for example, a mobile station. Each satellite can communicate the received reverse link signals to, for example, a base station or gateway where the signals can be combined to increase signal quality. A mobile station receives forward link signals from the primary satellite and monitors a signal quality from the primary satellite and from a secondary satellite. If the signal quality from the primary satellite drops below a threshold value, the communication signal is transferred to the secondary satellite.

Abstract: Methods and apparatus are disclosed to provide orthogonal multiple access communication in a return link of a satellite communication system. In one embodiment, a closed loop control of a transmit parameter associated with transmission of signals may be performed. In addition, changes in motion of a terminal are monitored such that an open loop control of the transmit parameter is performed, if the detected change meets a certain threshold. For example, an open control is performed if an abrupt or sudden motion is detected.

Abstract: A broadband terrestrial message delivery system includes a plurality of wireless communication devices (WCDs), each including a receiver and transmitter, the WCDs capable of not only receiving messages destined for a subscriber associated with a particular WCD, but further capable of acting as a relay point to move messages to and from other subscribers. Message diffusion includes relaying the messages in accordance with all earmark that specifies both the total number of times (N) a message is to be repeated, and the number of times (i) the received message has already been repeated. Methods of improving the spectral efficiency of such a message diffusion architecture include adding a propagation ring width control parameter (J) to the earmark such that a WCD acting in relay mode transmits no more than J repetitions of the message; and providing sectorization such that several sectorized message pathways in a cell may be simultaneously active.

Abstract: Aspects describe utilizing the Internet capability in mobile devices/networks to deliver broadcast multimedia to a device. The broadcast can be video, audio, and so forth. Initially the broadcast multimedia is transmitted at high data rates (and in unicast mode) in order for a buffer associated with mobile device to be built to a very long buffer length. When the long buffer length is reached, the multimedia can be delivered at real-time rates. The multimedia delivered at real times rates can be unicast mode or in multicast mode. If the buffer is depleted, a mobile device that is part of a multicast group can autonomously disassociated from the group until the buffer length is restored.