Multi-access CS-P/CD-E system and protocols on satellite channels applicable to a group of mobile users in close proximity

• US 6,049,548 A
• Filed: 04/28/1997
• Issued: 04/11/2000
• Est. Priority Date: 11/22/1996
• Status: Expired due to Term

• Current Assignee: Harris Corporation (L3Harris Technologies, Inc.)
• Original Assignee: Stanford Telecommunications, Inc. (Nokia Corporation)
• Inventors: Schuchman, Leonard, Bruno, Ronald
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): Vanderpuye, Ken
• Application Number:
  US08/846,491
• Time in Patent Office: 1,079 Days
• Field of Search: 370/445, 370/319, 370/338, 370/344, 370/276, 370/279, 370/281, 455/518, 455/519, 455/520, 455/12.1, 455/13.1, 455/528, 455/458, 342/352, 342/353, 342/456, 342/30, 342/33, 342/38, 342/39, 342/42, 342/43, 342/44, 342/45, 342/46
• US Class Current: 370/445
• CPC Class Codes: H04B 7/18539 Arrangements for managing radio, resources, i.e. for establishing or releasing a connection
• CPC Class Codes: H04B 7/2041 Spot beam multiple access

Abstract

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_l and a common outbound channel (from hub) frequency F_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 F₁, and a device to indicate the status of the carrier outbound channel, which controls the ability to transmit on the inbound channel.

Claims

1. In a multiple access RF communication system in which a plurality of mobile user transceivers communicate with a central hub transceiver over long delay channels, and wherein groups of mobile user transceivers in close proximity with each other share a common multi-access inbound channel frequency F₁ and a common outbound channel, frequency F_o, the improvement comprising:

each said mobile user transceiver including a continuously listening proximity receiver for the inbound channel and a half-duplex transceiver on the inbound channel means for determining the busy or idle status of said common inbound frequency F_l, and means to indicate the status of said carrier outbound channel and control the ability to transmit on the inbound channel.

2. The multiple access RF communication system defined in claim 1 wherein said central hub transceiver communicates through an earth orbiting satellite and said earth orbiting satellite transmits to earth a spatial beam which is divided into a plurality of proximity regions on earth, and each mobile user is adapted to use channel sense via proximity to determine the status of a said multi-access inbound channel.

3. The multiple access RF communication system defined in claim 1 wherein said mobile user transceiver includes a visual indicator of the status of said multi-access inbound channel.

4. The multi access RF communication system defined in claim 1 wherein a controlled aircraft includes a mobile user transceiver and said central hub transceiver communicates flight control information to said controlled aircraft via said mobile user transceiver.

5. The multi access RF communications system defined in claim 4 wherein each said transceiver is adapted to respond to an airport distributed cell-like communication signal using power control and said transceiver can be used for terminal voice, data and airport surveillance.

6. In 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 frequency F₁ and a common outbound channel frequency F_o, the improvement comprising a simplex receiver at the outbound channel for receiving messages from a central controller and a half-duplex transceiver at the inbound multi-access channel for transmission of messages to the hub, listening to the channel to ensure that the channel is not busy before transmitting, and listening to the channel to extract data from proximity mobiles that may be transmitting a message to the central controller.

7. In a multiple access RF communication system in which a plurality of mobile aircraft user transceivers communicate with a central hub transceiver through an earth orbiting satellite, and wherein groups of mobile aircraft user transceivers in close proximity with each other share a common multi-access inbound frequency F₁ and a common outbound channel frequency F_o, the improvement comprising means forming voice and data communication channels, said data channels used for dependent surveillance for aircraft, whereby a mobile aircraft user transceiver announces its presence to an air traffic controller when it enters a proximity region and then is regularly polled by the traffic controller, and sends its position, speed, heading and other data in response to the poll by the traffic controller.

8. In a multiple access RF communication system in which a plurality of mobile aircraft user transceivers communicate with a central hub transceiver through an earth orbiting satellite, and wherein groups of mobile aircraft user transceivers in close proximity with each other share a common multi-access (MA) inbound frequency F₁ and a common outbound channel frequency F_o, the improvement comprising a method of aircraft collision avoidance wherein use by the mobile aircraft user transceiver of said inbound data channel for air-to-air collision avoidance wherein a mobile aircraft user transceiver detects the presence of another aircraft user transceiver in the proximity region by listening in on the MA inbound channel, learning the position and vector of that proximity aircraft by demodulating and interpreting the navigation data that is sent by that mobile aircraft user transceiver, and finally by taking measures to avoid that aircraft if they are on a collision course.

9. A system for avoiding aircraft collisions in which each aircraft has an RF transceiver;

a multi-beam RF communication system comprising an orbiting satellite relay which transmits to earth on one or more satellite beams, each satellite beam transmits voice, data, surveillance report back requirements and the retransmission of inbound surveillance reports from aircraft transceivers in the beam and aircraft transceivers near the beam'"'"'s boundary so that each aircraft transceiver can demodulate and interpret the positional data transmitted via the satellite relay and determine if any aircraft is a collision threat and if so take measures to avoid the aircraft presenting a collision threat.