Stanford Telecommunications, Inc.

Itt Manufacturing Enterprises, Inc.

Exelis Inc.

Other

Ronald C Bruno

Leonard Schuchman

Lloyd Engelbrecht

Aaron Weinberg

Charles Moses

Boris Veytsman

Edward J Zakrzewski

Steve Greenberg

John Kefaliotis

Robert McCarthy

Kenneth D Cunningham

Robert Rennard

Christian Ramsey

Lawrence W Krebs

Hatch Graham, Iii

John E Miller

Robert J Sims

David Schuchman

Christopher Jason Berger

G Daniel Urban

Ronald H Pawlikowski, Jr

James Mathew Keller

A registration authority (RA) server registers unmanned aerial vehicles (UAVs) and their owners/operators (O/O). A UAV is maintained in a flight lock state until a flight plan request from the O/O is approved by the RA, which sends an key-signed approval to unlock the UAV's flight lock. The RA server evaluates a UAV's proposed flight plan based on the attributes of the O/O and UAV, the location and time of the requested flight plan, and a set of flight rules and exclusion zones that are developed in view of privacy assurance, security assurance, flight safety assurance, and ground safety assurance. The flight plan key-signed approval supplied to the UAV by the RA server specifies an inclusion zone that corresponds to a flight plan trajectory to be followed. Once in flight, the UAV maintains real-time knowledge of its position and time to ensure its flight remains within the approved inclusion zone.

Process and system to register and regulate unmanned aerial vehicle operations

System and methods for reducing redundant messages broadcast in an Automatic Dependent Surveillance-Broadcast (ADS-B) system. For a given target, a controller determines the relevant customers that should receive information about the target, identifies all of the ground stations that can be satisfactorily heard by the relevant customers, and then identifies a smaller subset of ground stations by selecting only those ground stations that are needed to reach all of the relevant customers. ADS-B messages are then broadcast to the relevant customers using only the smaller subset of ground stations.

Transmission scheduling for ADS-B ground systems

Shortcomings in conventional Very High Frequency (VHF) Digital Link Mode 3 (VDL-3) communication techniques for implementing air/ground (A/G) diversity site group (DSG) communication are identified and resolved. Beacon schedules are used to coordinate the use of VDL-3 TDMA management slots. Limited autonomy local address management techniques are used to distribute blocks of unique addresses to the ground stations (GS's) of a DSG from a common base of local addresses maintained at a control site, thus assuring that the respective ground stations assign a unique local identifier to each aircraft supported by the DSG. Aircraft supported by a DSG are polled to obtain time of arrival (TOA) and signal quality information used to: intelligently select the transmit ground station and the receive ground station used for communication between an specific aircraft and the control site; and, intelligently manage contiguous communication handoffs of aircraft from one ground station to another ground station of the DSG.

Method for diversity site group operations in air/ground communications

A remote communications terminal accesses a terrestrial network or information source via a SATCOM link with an earth station hub linked to the network or information source. Information throughput adaptation (ITA) is employed on the SATCOM link to maximize information throughput over the SATCOM link while ensuring acceptable signal quality under varying rain fading conditions. Sufficient power margin is built into the SATCOM link such that, under severe rain fading conditions, the lowest system throughput rate still provides acceptable signal quality. Under lesser rain fading conditions, the data throughput rate is increased via more bandwidth efficient modulation and coding schemes permitted by the higher signal quality which results from greater power margin. The earth station hub and remote terminals monitor the signal quality and communicate to adaptively adjust the modulation and coding used on the forward and return links to maximize information throughput under varying rain fading conditions.

Methods and apparatus for mitigating rain fading over SATCOM links via information throughput adaptation

Positioning system for locating a mobile body comprising a plurality of earth based spread spectrum (SS) broadcasting stations arranged geographically in a cellular pattern. Each SS broadcasting station include a modulator providing a channel signal structure which is substantially orthogonal with respect to adjacent stations in the cellular pattern, each channel signal including navigation beacon data including a unique beacon identification, station latitude and longitude, time_slot and phase characterizations and selected parameters of adjacent stations. In one embodiment, each modulator provides a chirped SS signal in which the navigation beacon is a frequency tone that is repeatedly swept over a selected frequency band for each station. In a further embodiment, each modulator provides a GPS like direct sequence SS signal in which the navigation beacon is a PN coded broadcast. A receiver on the mobile body receives the SS signals from at least three of the SS broadcasting stations and determines the location thereof. A fourth SS broadcasting station provides altitude CPS satellite signals can be used for timing control.

Cellular positioning system (CPS)

A cellular telephone system having three or more cell sites with each cell site having a source of cellular communication signals and an RF transmitter and antenna for broadcasting the cellular communication signals. A direct sequence spread spectrum waveform carrying navigation signals is embedded in the cellular communication signals, including controlling the signal strength of the navigation signals so that the combined energy of the navigation signals from all cell sites at any location is at least a predetermined energy level below the energy level of the cellular communication signals. Each cell site includes timing for timing the operation of a GPS receiver. An RF signpost system comprising a plurality of low powered RF broadcast stations, one each at a plurality of scattered geographic locations, each low powered RF broadcast station broadcasting a direct sequence spread spectrum digital RF waveform and means to modulate the digital RF waveform with location information identifying the geographic locations, respectively.

Position enhanced communication system including system for embedding CDMA navigation beacons under the communications signals of a wireless communication system

A mobile unit includes a network receiver, such as a GSM telephone, for communication with a wireless network, and a navigation receiver, such as a global positioning system (GPS) receiver for receiving navigation signals. The navigation receiver includes a vector delay lock loop (VDLL) that receives information concerning the navigation sources, such as satellite data messages, transmitted over a common broadcast channel of the wireless network, and receives navigation signals from the navigation receiver. The VDLL uses the navigation signals received from navigation sources that are not obscured and uses satellite data messages broadcast over the wireless network to track a navigation signal that is received only intermittently due, for example, to the navigation source being obscured from view of the mobile unit.

Hybrid system for position determination by a mobile communications terminal

An accessory device for portable telephones which provides simultaneous functionality of a hands-free accessory device and a data-in-voice modem enabling a portable telephone to be used in a vehicle such that the driver can be engaged in a hands-free conversation at the same time as data (such as GPS position information) is being sent over the same cellular voice channel.

System for providing a simultaneous data and voice channel within a single channel of a portable cellular telephone to provide position-enhanced cellular services (PECS)

A method of avoiding near-far interference problems in a cellular ray of navigation signal beacons having selected CDMA or GPS-like navigation signals. The navigation signals from adjacent navigation signal beacons are pulsed so that adjacent navigation signal beacons do not broadcast navigation signals simultaneously and the multiple frequencies are coordinated in a time divisional multiplex manner. In another aspect, the near-far interference problem is avoided by using multiple frequencies in time division multiplexing and coordinating the use of the multiple frequencies and the time division multiplexing to assure avoidance of the near-far interference problem.

Method of avoiding near-far interference problems in an array of

Positioning system for locating a mobile body comprising a plurality of earth based spread spectrum (SS) broadcasting stations arranged geographically in a cellular pattern. Each SS broadcasting station include a modulator providing a channel signal structure which is substantially orthogonal with respect to adjacent stations in the cellular pattern, each channel signal including navigation beacon data including a unique beacon identification, station latitude and longitude, time.sub.-- slot and phase characterizations and selected parameters of adjacent stations. In one embodiment, each modulator provides a chirped SS signal in which the navigation beacon is a frequency tone that is repeatedly swept over a selected frequency band for each station. In a further embodiment, each modulator provides a GPS like direct sequence SS signal in which the navigation beacon is a PN coded broadcast. A receiver on the mobile body receives the SS signals from at least three of the SS broadcasting stations and determines the location thereof. A fourth SS broadcasting station provides altitude. CPS satellite signals can be used for timing control.

A multiple access RF communication system in which a plurality of mobile user transceivers communicate with a central hub transceiver through an earth orbiting satellite, and wherein groups of mobile user transceivers in close proximity with each other share a common multi-access inbound (to hub) frequency F.sub.l and a common outbound channel (from hub) frequency F.sub.o. Each said mobile user transceiver includes a continuously listening receiver for the outbound channel and a half-duplex transceiver on the inbound channel, determining the busy or idle status of the common inbound frequency F.sub.1, and a device to indicate the status of the carrier outbound channel, which controls the ability to transmit on the inbound channel.

Multi-access CS-P/CD-E system and protocols on satellite channels

A digital broadcast system, comprising a master radio broadcast station located at a main predetermined location for formatting and broadcasting a plurality of channels of digitized program data in a spread spectrum, time and frequency hopping waveform to remote mobile and stationary receivers. A plurality of relatively low power range extension radio broadcast stations are provided, each said range extension station being located in selected areas and, each range extension station being adapted to receive and store one or more channels of program information from the master station. A separate program distribution system coupling the received and store of each range extension radio broadcast station with the master radio broadcast station, said separate distribution system, including, for each range extension station at least one path selected form satellite, microwave, fiber-optic, coaxial cable and telephone paths, for coupling one or more channels of program information to each range extension station. The channels of digital data re-broadcast from each of the range extension radio broadcast stations is synchronized with broadcasts from the master radio broadcast station such that a mobile receiver traveling between edges of reception of two or more low power range extension radio broadcast stations does not evidence interference therebetween.

Digital broadcast system

Air traffic surveillance and communication system

A GPS system has a plurality of satellites transmitting time and location data over radio frequency signals which enable a mobile GPS receiver on the ground to determine its position, includes a source of satellite data message block containing the ephemeris and time modes of the GPS satellites which is independent of the satellites, and an independent cellular telephone channel having a voice channel, a data-in-voice modem including a notch filtering circuit in the voice channel (transmits and receive) and circuits for inserting and retrieving data in and from the notch for accessing said satellite data message block and controller means connecting said satellite message data block to said mobile GPS receiver.

Growing community of inventors

Arlington, VA, United States of America

Ronald C Bruno