Balloon with Pressure Mechanism to Passively Steer Antenna

Patent metadata

Field	Value
Publication number	US-2016149301-A1
Application number	US-201615003760-A
Country	US
Kind code	A1
Filing date	Jan 21, 2016
Priority date	Apr 16, 2013
Publication date	May 26, 2016
Grant date	—

Abstract

Methods and apparatus are disclosed for passively steering an antenna disposed on a balloon in a balloon network. An example balloon involves: (a) an antenna and (b) a pressure-sensitive mechanism in mechanical communication with the antenna such that a change in the balloon's altitude causes at least an element of the antenna to rotate upward or downward, a separation distance between two or more radiating elements to increase or decrease, or a separation distance between the two or more radiating elements and a reflector to increase or decrease.

First claim

What is claimed is:

1 . A balloon, comprising:
an antenna; and a pressure-sensitive mechanism in mechanical communication with the antenna such that a change in the balloon's altitude causes at least an element of the antenna to rotate upward or downward, a separation distance between two or more radiating elements to increase or decrease, or a separation distance between the two or more radiating elements and a reflector to increase or decrease.

2 . The balloon of claim 1 , wherein the pressure-sensitive mechanism comprises an aneroid or a Bourdon tube.

3 . The balloon of claim 1 , wherein the pressure-sensitive mechanism comprises an aneroid, wherein the aneroid defines an enclosed chamber with a first surface, a second surface and at least one collapsible sidewall disposed between the first surface and the second surface, wherein the chamber contains a partial vacuum, wherein the first surface is fixedly mounted and the second surface is movable relative to the first surface, and wherein contraction of the aneroid causes an element of the antenna to rotate upward and expansion of the aneroid causes an element of the antenna to rotate downward.

4 . The balloon of claim 1 , further comprising a calibration system comprising a zero-power-hold actuator and a processor, wherein the zero-power-hold actuator is in mechanical communication with the antenna.

5 . The balloon of claim 4 , wherein the zero-power-hold actuator comprises one of a piezoelectric motor, a servomotor, or a solenoid.

6 . The balloon of claim 4 , wherein the calibration system further includes a movable support, wherein the zero-power-hold actuator acts upon the movable support.

7 . The balloon of claim 6 , wherein the pressure-sensitive mechanism comprises an aneroid and wherein a first surface of the aneroid is coupled to the movable support.

8 . The balloon of claim 7 , wherein a base end of the antenna is statically mounted to a second surface of the aneroid.

9 . The balloon of claim 6 , wherein the calibration system further includes an adjustment element that acts as an interface between the zero-power-hold actuator and the movable support.

10 . The balloon of claim 9 , wherein the adjustment element comprises a set screw or a magnet.

11 . The balloon of claim 6 , wherein the calibration system further includes a tension spring with a first end and a second end, wherein the first end of the tension spring is coupled either directly or indirectly to the antenna, wherein the second end of the tension spring is coupled to the movable support.

12 . The balloon of claim 3 , further comprising a counterweight in the form of a biasing spring, wherein the biasing spring has a first end that is fixedly mounted and a second end that is coupled to the movable second surface of the aneroid.

13 . The balloon of claim 3 , wherein the second surface of the aneroid is arranged relative to the first surface of the aneroid such that the second surface moves along a shared axis with the first surface.

14 . The balloon of claim 3 , wherein the second surface of the aneroid is arranged to pivot relative to the first surface of the aneroid.

15 . The balloon of claim 1 , wherein the pressure-sensitive mechanism comprises an aneroid, wherein the aneroid defines an enclosed chamber with a flexible surface that expands and contracts, and wherein a contraction of the aneroid causes an element of the antenna to rotate upward and an expansion of the aneroid causes an element of the antenna to rotate downward.

16 . The balloon of claim 1 , wherein the pressure-sensitive mechanism comprises a Bourdon tube, wherein a contraction of the Bourdon tube causes an element of the antenna to rotate upward and an expansion of the Bourdon tube causes an element of the antenna to rotate downward.

17 . The balloon of claim 4 , wherein the calibration system further includes memory accessible by the processor and machine-language instructions stored in the memory that when executed by the processor causes the balloon to carry out functions including:
receiving an indication of at least one of a change in altitude, a change in latitude, a change in the distance to a second balloon in the network or a change in antenna signal beam width from at least one of a ground station, a second balloon, or an altimeter; determining whether a positioning threshold has been exceeded; and in response to a determination that the positioning threshold has been exceeded, actuating the zero-power-hold actuator.

18 . A method comprising:
operating a first balloon at a first altitude, wherein the balloon comprises an antenna, and a pressure-sensitive mechanism in mechanical communication with the antenna; initiating an altitude change to move the balloon to a second altitude that is different from the first altitude; and in response to the altitude change, adjusting the position of the antenna, wherein adjusting the position of the antenna comprises: if the second altitude is higher than the first altitude, expanding a component of the pressure-sensitive mechanism and rotating the antenna beam pattern downward; and if the second altitude is lower than the first altitude, contracting the component of the pressure-sensitive mechanism and rotating the antenna beam pattern upward.

19 . The method of claim 18 , further comprising:
receiving an indication of at least one of a change in altitude, a change in latitude, a change in the distance to a second balloon in a network or a change in antenna signal beam width from at least one of a ground station, a second balloon, or an altimeter determining whether a positioning threshold has been exceeded; and in response to a determination that the positioning threshold has been exceeded, actuating a zero-power-hold actuator.

20 . The method of claim 19 , wherein the positioning threshold is a function of at least one of an altitude of the first balloon, an altitude of the second balloon, the distance from the first balloon to the second balloon, the antenna signal beam width of the first balloon or the antenna signal beam width of the second balloon.

Assignees

• Google Inc

Inventors

• Behroozi Cyrus
• Teller Eric
• Devaul Richard W

Classifications

• H01Q3/06

  over a restricted angle · CPC title

• H01Q3/08 Primary

  for varying two co-ordinates of the orientation · CPC title

• H01Q1/082

  Balloon antennas · CPC title

• H01Q15/14

  Reflecting surfaces; Equivalent structures {(electromagnetic shields H01Q1/526)} · CPC title

• H01Q1/28

  Adaptation for use in or on aircraft, missiles, satellites, or balloons · CPC title