Vehicle with a radio frequency device and associated methods
A vehicle may comprise a frame, a propulsion arrangement configured to orient the frame, and an antenna carried by the frame. The antenna may include a housing, a base carried by the housing, a pair of spaced apart antenna elements carried by the base, and a phase shifter coupled to the pair of antenna elements to define an antenna pattern having a pair of opposing nulls. An RF receiver is coupled to the antenna. A controller may control the propulsion arrangement to orient the frame to steer the antenna pattern based upon the RF receiver.
1 . A vehicle comprising:
a frame;
a propulsion arrangement configured to orient the frame;
an antenna carried by the frame and comprising
a housing,
a base carried by the housing,
a pair of spaced apart antenna elements arranged in a linear array, each antenna element comprising an elongate omni-directional antenna element having a proximal end coupled to the base and a distal end extending outwardly from the base, and
a phase shifter coupled to the pair of antenna elements to define an antenna pattern having a pair of opposing nulls;
an RF receiver coupled to the antenna; and
a controller configured to control the propulsion arrangement to orient the frame to steer the antenna pattern based upon the RF receiver, and configured to selectively operate a first one of the pair of spaced apart antenna elements while selectively switching out a second one of the pair of spaced apart antenna elements based upon a received signal strength being above a threshold.
2 . The vehicle of claim 1 wherein the pair of opposing nulls in the antenna pattern are 180 degrees apart.
3 . The vehicle of claim 1 wherein the RF receiver operates over a frequency range, and the pair of opposing nulls are aligned over the frequency range.
4 . The vehicle of claim 1 wherein the controller orients the frame to steer the antenna pattern so that one of the nulls is directed toward an RF interference source.
5 . The vehicle of claim 1 wherein the phase shifter comprises at least one discrete component.
6 . The vehicle of claim 1 wherein the phase shifter comprises a pair of feeds coupled to respective antenna elements in a reverse polarity configuration.
7 . The vehicle of claim 1 wherein the controller orients the frame to steer the antenna pattern based upon received signal strength.
8 . The vehicle of claim 1 wherein a spacing between the pair of antenna elements is in a range of 0.1-0.7 wavelength of an operating frequency of the RF receiver.
9 . The vehicle of claim 1 wherein each elongate, omni-directional antenna element comprises a dipole antenna element.
10 . The vehicle of claim 1 wherein the RF receiver comprises at least one of a frequency-hopping spread spectrum (FHSS) receiver, a direct sequence spread spectrum (DSSS) receiver, and an orthogonal frequency-division multiplexing (OFDM) receiver.
11 . The vehicle of claim 1 wherein the vehicle is unmanned.
12 . A vehicle comprising:
a frame;
a propulsion arrangement configured to orient the frame;
an antenna carried by the frame and comprising
a housing,
a base carried by the housing,
a pair of spaced apart elongate, dipole antenna elements arranged in a linear array, each elongate, dipole antenna element having a proximal end coupled to the base and a distal end extending outwardly from the base, and
a phase shifter coupled to the pair of antenna elements to define an antenna pattern having a pair of opposing nulls;
an RF receiver coupled to the antenna; and
a controller coupled to the RF receiver and configured
to control the propulsion arrangement to orient the frame to rotate the antenna pattern while determining received signal strengths of received RF signals, configured to stop rotation of the antenna pattern at a desired received signal strength, and configured to selectively operate a first one of the pair of spaced apart elongate, dipole antenna elements while selectively switching out a second one of the pair of spaced apart elongate, dipole antenna elements based upon a received signal strength being above a threshold.
13 . The vehicle of claim 12 wherein the pair of opposing nulls in the antenna pattern are 180 degrees apart.
14 . The vehicle of claim 12 wherein the RF receiver operates over a frequency range, and the pair of opposing nulls are aligned over the frequency range.
15 . The vehicle of claim 12 wherein the controller orients the frame to steer the antenna pattern so that one of the nulls is directed toward an RF interference source.
16 . The vehicle of claim 12 wherein a spacing between the pair of antenna elements is in a range of 0.1-0.7 wavelength of an operating frequency of the RF receiver.
17 . The vehicle of claim 12 wherein the RF receiver comprises at least one of a frequency-hopping spread spectrum (FHSS) receiver, a direct sequence spread spectrum (DSSS) receiver, and an orthogonal frequency-division multiplexing (OFDM) receiver.
18 . The vehicle of claim 12 wherein the vehicle is unmanned.
19 . A method for operating a vehicle with a radio frequency (RF) device, the RF device comprising an antenna comprising a housing, a base carried by the housing, a pair of spaced apart antenna elements arranged in a linear array, each antenna element comprising an elongate omni-directional antenna element having a proximal end coupled to the base and a distal end extending outwardly from the base, and a phase shifter coupled to the pair of antenna elements to define an antenna pattern having a pair of opposing nulls, the method comprising:
operating an RF receiver coupled to the antenna;
operating a controller to control the propulsion arrangement to orient the frame to steer the antenna pattern based upon the RF receiver, and to selectively operate a first one of the pair of spaced apart antenna elements while selectively switching out a second one of the pair of spaced apart antenna elements based upon a received signal strength being above a threshold.
20 . The method of claim 19 wherein the pair of opposing nulls in the antenna pattern are 180 degrees apart.
21 . The method of claim 19 wherein the RF receiver operates over a frequency range, and the pair of opposing nulls are aligned over the frequency range.
22 . The method of claim 19 wherein the controller orients the frame to steer the antenna pattern so that one of the nulls is directed toward an RF interference source.
23 . The method of claim 19 wherein the controller orients the frame to steer the antenna pattern based upon received signal strength.
24 . The method of claim 19 wherein a spacing between the pair of antenna elements is in a range of 0.1-0.7 wavelength of an operating frequency of the RF receiver.
25 . The method of claim 19 wherein each elongate, omni-directional antenna element comprises a dipole antenna element.
26 . The method of claim 19 wherein the RF receiver comprises a frequency-hopping spread spectrum (FHSS) receiver.
27 . The method of claim 19 wherein the vehicle is unmanned.