Ground-to-air telephone calling system and related method

• US 5,278,891 A
• Filed: 09/16/1991
• Issued: 01/11/1994
• Est. Priority Date: 04/29/1988
• Status: Expired due to Term

• Current Assignee: MCI LLC (Verizon Communications Inc.)
• Original Assignee: Mobile Telecommunications Technologies, LLC (Mobitex Technology AB)
• Inventors: Oswalt, Ernest A., Hays, William D., Bhagat, Jai P.
• Primary Examiner(s): Ng, Jin F.
• Assistant Examiner(s): Cumming, William D.
• Application Number:
  US07/759,626
• Time in Patent Office: 848 Days
• Field of Search: 340/825.04, 370/95, 375/116, 379/58, 379/60, 379/61, 379/63, 380/9, 455/12, 455/13, 455/56
• US Class Current: 455/431
• CPC Class Codes: H04B 7/18508 with satellite system used as relay, i.e. aeronautical mobile satellite service

Abstract

A ground-to-air telephone calling system is provided including a computer for receiving an airborne telephone number and a call-back number from a calling party and forming the telephone numbers into a data signal comporting with existing protocol filed in the FCC, an uplink unit for uplinking the data signal to a satellite and a plurality of downlink stations for receiving the data signal from the satellite; a plurality of ground stations corresponding to each of the downlink units for receiving the data signals and passing a call signal identifying the airborne telephone and particular ground station to a corresponding transmit/receive unit for subsequent transmission to the aircraft; a call being initiated from the ground station to the calling party over the public switched telephone network if the aircraft responds to the call signal.

Claims

1. A system for establishing a communication link between a ground based caller and a telephone unit aboard an airborne aircraft, comprising:

means for generating a first signal in response to a telephone call from said ground based caller, said first signal including a telephone number of said ground based caller;

means for transmitting said first signal to each of a plurality of ground units, each of said plurality of ground units comprising;

means for receiving said first signal;

means for storing said telephone number of said ground based caller;

means for generating a second signal in response to said first signal, said second signal not including said telephone number of said ground based caller; and

means for transmitting said second signal throughout a corresponding region;

wherein said telephone unit is capable of responding to said second signal from a ground unit corresponding to a region in which said aircraft is located and of transmitting a third signal to said ground unit corresponding to the region in which said aircraft is located, said third signal not including said telephone number of said ground based caller;

each of said plurality of ground units further comprising;

means for receiving said third signal from said telephone in said aircraft when said aircraft is located in the corresponding region; and

means for establishing a telephone connection between the ground unit and said ground based caller in response to said third signal using said stored telephone number of said ground base caller.

2. A system according to claim 1, wherein said second signal includes data identifying said telephone unit.

3. A system according to claim 1, wherein each of said plurality of ground units further includes delay means for delaying transmission of said second signals by a predetermined time period when the ground unit is busy.

4. A system according to claim 1, further comprising means for selectively activating only predetermined ones of said plurality of ground units.

5. A method of establishing a communication link between a ground based caller and a telephone unit aboard an airborne aircraft, comprising the steps of:

generating a first signal in response to a telephone call from said ground based caller, said first signal including a telephone number of said ground based caller;

transmitting said first signal to a plurality of ground stations;

receiving said first signal at each of said plurality of ground stations;

storing said telephone number of said ground based caller at each of said plurality of ground stations;

generating a second signal at each of said plurality of ground stations in response to said first signal, said second signal not including said telephone number of said ground based caller;

transmitting said second signal throughout regions corresponding to each of the ground stations;

receiving one of said second signals at said telephone unit in said airborne aircraft;

generating a third signal at said telephone unit in response to said one of said second signals, said third signal not including said telephone number of said ground based caller;

transmitting said third signal to a ground station which transmitted said one of said second signals; and

calling said ground based caller from said ground station which transmitted said one of said second signals in response to said third signal using said stored telephone number of said ground based caller.

6. A method according to claim 5, wherein said second signal includes data identifying said telephone unit.

7. A method according to claim 5, further comprising the step of delaying transmission of said second signals by a predetermined time period when a corresponding ground station is busy.

8. A method according to claim 5, further comprising the step of selectively activating only predetermined ones of said plurality of ground stations.