TETHERED AIRBORNE COMMUNICATIONS AND INFORMATION TRANSFER SYSTEM

• US 3,742,358 A
• Filed: 12/30/1970
• Issued: 06/26/1973
• Est. Priority Date: 12/30/1970
• Status: Expired due to Term

• Current Assignee: Richard S. Cesaro
• Original Assignee: Richard S. Cesaro
• Inventors: Cesaro, Richard S.
• Primary Examiner(s): Mayer, Albert J.
• Application Number:
  US05/102,597
• Time in Patent Office: 909 Days
• Field of Search: 325/4,118,115,113,185,3,5,15 343/756.5,758,705
• US Class Current: 455/9
• CPC Class Codes: H04B 7/185 Space-based or airborne stations; Stations for satellite systemsH04B7/204 takes precedence
• CPC Class Codes: H04B 7/18504 Aircraft used as relay or high altitude atmospheric platform

Abstract

A tethered balloon including means for controlling the height thereof is utilized as an airborne platform for transmitting and receiving apparatus including a multiple antenna assembly. The antenna assembly is suspended from a gimbal or ball joint configuration attached to the balloon so that it is gravity stabilized in the vertical plane. The antenna assembly itself is comprised of a plurality of independently rotatable coaxial shafts having respective antenna means coupled thereto. The shafts are hung from a pendulum arm member which is freely moveable within a vertical cone angle limit of 45* and maintains vertical orientation to within + OR - 2*. The rotation of each of the coaxial shafts is independently controlled from a ground station by means of a control signal to selectively point each antenna means in a predetermined compass direction. Additionally, each coaxial shaft couples respective transmitter-receiver means to its antenna means in order to provide selective signal transfer between the ground station and/or other similar airborne systems.

Claims

1. A system for receiving and transmitting electromagnetic radiation including various types of radio signals, TV signals as well as other types of information and/or data communication signals, comprising, in combination:

airborne apparatus for providing a mounting platform for electronic transmitting and receiving apparatus;

a gravity stabilized antenna assembly suspended from said airborne apparatus, said antenna assembly being comprised of (a) a mounting base attached to the underside of said airborne apparatus including a ball-joint housing depending therefrom, said housing having a downwardly depending side portion and a lower end portion having a circular opening therein, said side portion also including an inwardly projecting ball bearing mount intermediate its length and a tapered race type ball bearing assembly having a concave bearing surface affixed thereto, a spherical member of predetermined diameter resting on said concave bearing surface, said diameter being of such a magnitude that the center of the sphere is located above the uppermost contact point between the spherical member and the ball bearing assembly, said opening additionally having an inwardly angulated circular damper member affixed thereto the outer surface of which defines a hypothetical cone having an apex at the center of said spherical member, (b) a pendulum arm member attached to one extremity to said spherical member and projecting through said damper member and being suspended therefrom in substantially vertical alignment, (c) a support member attached to the other extremity of said arm member, and (d) a plurality of coaxial cylindrical shafts which are independently rotatable about the central longitudinal axis thereof mounted on said support member and wherein selected shafts of said plurality of shafts each additionally includes separate electrical signal transmission line means carried by the respective shaft side wall for coupling electrical signals from one end of the respective shaft to substantially the opposite end thereof;

respective antenna means mounted at said one end of said selected coaxial shafts and being coupled to said respective transmission line means;

a ground station for controlling said airborne apparatus;

antenna directional control means coupled to said selected coaxial shafts for properly pointing the respective antenna means in a predetermined compass heading in a substantially horizontal plane, said control means including a telemetry control radio link with said ground station whereby each antenna means is independently oriented in response to a compass heading signal transmitted to said control means from said ground station;

respective electrical signal transmitter-receiver apparatus located on said airborne apparatus and coupled to said antenna means and additionally including respective electrical slip ring assemblies integral with said selected shafts, coupled to the opposite end of said respective transmission line means; and

electrical signal command and control apparatus, located on said airborne apparatus, coupled to each of said signal transmitterreceiver apparatus for selectively controlling the operation of the respective signal transmitter-receiver apparatus to provide, (1) an '"'"''"'"''"'"''"'"'up-down'"'"''"'"''"'"''"'"' communication link with said ground station including the transfer of command and control signals therefrom as well as the transfer of communications signals on one or more communications channels to said airborne apparatus including said signal transmitter-receiver apparatus by means of at least one of said antenna means, (2) a transmitting and receiving link for a local ground area coverage by at least one other of said antenna means, and (3) a communication air-to-air relay link along a substantially horizontal direction by at least one of yet another of said antenna means.

2. The invention as defined by claim 1 wherein said airborne apparatus comprises a lighter than air vehicle.

3. The invention as defined by claim 2 wherein said lighter than air vehicle comprises a balloon.

4. The invention as defined by claim 1 wherein said directional control means includes a flux gate transmitter at said ground station for providing a compass heading signal for each of said antenna means via said '"'"''"'"''"'"''"'"'up-down'"'"''"'"''"'"''"'"' link and wherein each of said selected coaxial shafts is coupled to a flux gate compass system and additionally including means responsive to the output of said compass system to rotate said shaft in a predetermined direction in accordance with said compass heading signal.

5. The invention as defined by claim 4 wherein said last-recited means comprises an electrical drive motor and an electrical servo system coupled between said flux gate compass system and said drive motor for controlling the operation of said drive motor.

6. The invention as defined by claim 1 wherein said signal transmitter-receiver apparatus includes means for multi-channel electrical signal communications.

7. In an electromagnetic signal communication system, a plurality of tethered aircraft disposed at predetermined heights above the surface of the earth in order to provide respective free space antenna platforms for electronic signal receiving and transmitting apparatus;

a ground based receiving and transmitting station located beneath each of said aircraft and including means for controlling the aircraft and means for transmitting and receiving a plurality of electrical signals to and from the respective aircrafT and means for transmitting at least a first and a second control signal thereto;

each of said aircraft additionally including a multiple antenna structure comprising a pendulum type gravity stabilized antenna mount comprised of (a) a mounting base attached to the underside of said airborne apparatus including a ball-joint housing depending therefrom, said housing having a downwardly depending side portion and a lower end portion having a circular opening therein, said side portion also including an inwardly projecting ball bearing mount intermediate its length and a tapered race type ball bearing assembly having a concave bearing surface affixed thereto, a spherical member of predetermined diameter resting on said concave bearing surface, said diameter being of such a magnitude that the center of the sphere is located above the uppermost contact point between the spherical member and the ball bearing assembly, said opening additionally having an inwardly angulated circular damper member affixed thereto the outer surface of which defines a hypothetical cone having an apex at the center of said spherical member, (b) a pendulum arm member attached at one extremity to said spherical member and projecting through said damper member and being suspended therefrom in substantially vertical alignment, (c) a support member attached to the other extremity of said arm member, and (d) a plurality of coaxial shafts attached to and suspended from said antenna mount in a substantially vertical direction and including electrically controlled means for independently rotating a selected number of said shafts about the center longitudinal axis thereof, said selected number of said coaxial shafts each additionally including separate transmission line means mounted within the respective shaft side wall and extending substantially between each end thereof, antenna means attached to the lower extremity of said selected number of coaxial shafts and coupled to the respective transmission line means, independent transmitter-receiver means and slip ring coupling means integral with said selected shafts coupled to the respective transmission line means at the other end of the respective shaft for receiving or transmitting signals to the respective antenna means;

means coupled to said selected number of coaxial shafts for rotating each shaft independently to the predetermined azimuth direction in accordance with a compass setting transmitted from said ground station via said first control signal transmitted from said ground station whereby at least one antenna means is directed toward said ground station, at least one other antenna means directed toward a predetermined local area under the respective aircraft as determined by the subtended radiation pattern of the antenna means, and at least one still another antenna means is directed toward another tethered aircraft of said plurality of aircraft; and

circuit means located on each said aircraft, being responsive to said second control signal transmitted from said ground station to selectively operate each said transmitter-receiver means to relay communication signals between adjacent tethered aircraft and to provide communication signal transfer between the respective ground stations and aircraft.

8. The invention as defined by claim 7 wherein said plurality of aircraft are comprised of lighter than air balloons and wherein said ground station additionally includes means for controlling the height of the respective balloons as well as means for monitoring the condition thereof.

9. The invention as defined by claim 8 wherein said first recited means comprises a tether cable and wherein said tether cable includes means for coupling electrical power from said ground station to said antenna platform.

10. The invention as defined by claim 7 wherein said at least one of said antenna means comprises a first type antenna, said at least one other antenna means comprises a second type antenna, and said at least one yet another antennA means comprises a third type antenna.

11. The invention as defined by claim 10 wherein said first type antenna comprises a spiral antenna, said second type antenna comprises a dish type antenna, and said third type antenna comprises a parabolic cylindrical type antenna.

12. The invention as defined by claim 7 wherein said means for transmitting and receiving a plurality of electrical signals comprises a multi-channel transmitter and a multichannel receiver of microwave signals.

13. The invention as defined by claim 12 and additionally including a frequency synthesizer coupled to said transmitter and said receiver for respectively coupling at least one local oscillator signal thereto for generating an IF signal.