Spatial diversity for relative position tracking
Vehicles and methods of navigating vehicles comprise at least three receiver antennae configured to receive radio frequency (RF) signals from one or more RF-transmitting antennae coupled to an object, receiver circuitry coupled to the receiver antennae to acquire the RF signals and to determine timing information from the acquired RF signals, memory storing information related to fixed distances between each receiver antenna and each other receiver antenna, a processor configured to determine a relative position of the vehicle with respect to the one or more RF-transmitting antennae based on the stored information related to the fixed distances between each receiver antenna and each other receiver antenna and on the timing information determined by the receiver circuitry, and a control system configured to control operation of the vehicle in response to the relative position of the vehicle with respect to the one or more RF-transmitting antennae determined by the processor.
1. A vehicle comprising:
at least three spatially separated receiver antennae configured to receive radio frequency (RF) signals from one or more RF-transmitting antennae coupled to an object;
receiver circuitry coupled to the at least three spatially separated receiver antennae to acquire the RF signals received by the at least three spatially separated receiver antennae and to determine timing information from the acquired RF signals;
memory storing information related to fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae;
a processor coupled to 1) the memory to access the stored information related to the fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae, and 2) the receiver circuitry to receive the timing information determined from the RF signals received by the at least three spatially separated receiver antennae, the processor being configured to determine a relative position of the vehicle with respect to the one or more RF-transmitting antennae based on the stored information related to the fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae and on the timing information determined by the receiver circuitry; and
a control system configured to control operation of the vehicle in response to the relative position of the vehicle with respect to the one or more RF-transmitting antennae determined by the processor.
2. The vehicle of claim 1 , wherein the RF signals received by the at least three receiver antennae include an absolute global position of the object and the processor determines an absolute global position of the vehicle based on the determined relative position of the vehicle with respect to the one or more RF-transmitting antennae and the absolute global position of the object.
3. The vehicle of claim 1 , wherein the receiver circuitry comprises a time of arrival module for each of the at least three receiver antennae and the timing information comprises time of arrival information.
4. The vehicle of claim 1 , wherein the receiver circuitry comprises a receiver channel that determines phase differences among the RF signals received by the at least three receiver antennae and the timing information comprises these phase differences.
5. The vehicle of claim 1 , wherein the object to which the one or more RF-transmitting antennae are coupled is a moving object.
6. The vehicle of claim 1 , wherein the object to which the one or more RF-transmitting antennae are coupled is a stationary object.
7. The vehicle of claim 1 , wherein the control system is in communication with a navigation system of the vehicle.
8. The vehicle of claim 1 , wherein the control system includes the processor.
9. The vehicle of claim 1 , wherein the receiver circuitry is configured to receive the RF signals across a wide band of frequencies and to detect a frequency at which the one or more RF-transmitting antennae are transmitting, and is communication with the processor to identify this frequency.
10. The vehicle of claim 9 , wherein the processor directs the RF transmitter to transmit RF signals at this frequency.
11. The vehicle of claim 1 , wherein the RF signals received by each of the at least three receiver antennae include at least two different frequencies.
12. The vehicle of claim 1 , further comprising:
at least one RF-transmitting antenna; and
a global positioning system (GPS) device configured to obtain an absolute position of the RF-transmitting antenna.
13. The vehicle of claim 12 , wherein the processor is configured to direct the RF-transmitting antenna to include the absolute position of the vehicle in RF signals transmitted by the RF transmitter.
14. The vehicle of claim 1 , wherein the vehicle is an unmanned, autonomously driven vehicle.
15. The vehicle of claim 1 , wherein the vehicle is a drone.
16. The vehicle of claim 1 , wherein the vehicle is a robot.
17. The vehicle of claim 1 , wherein the vehicle and the object are automobiles.
18. A network comprising:
at least one object coupled to one or more radio frequency (RF) transmitting antennae;
a plurality of vehicles, each vehicle comprising:
at least one RF-transmitting antenna that transmits RF signals;
at least three spatially separated receiver antennae configured to receive RF signals transmitted by the one or more RF-transmitting antennae coupled to the at least one object and by the at least one RF-transmitting antenna of one or more other vehicles of the plurality of vehicles;
receiver circuitry coupled to the at least three spatially separated receiver antennae to acquire the RF signals received by the at least three spatially separated receiver antennae and to determine timing information from the acquired RF signals;
memory storing information related to fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae;
a processor coupled to 1) the memory to access the stored information related to the fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae, and 2) the receiver circuitry to receive the timing information determined from the RF signals received by the at least three spatially separated receiver antennae, the processor being configured to determine a relative position of the vehicle with respect to each RF-transmitting antenna from which RF signals are received based on the stored information related to the fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae and on the timing information determined by the receiver circuitry; and
a control system configured to control operation of the vehicle in response to the relative position of the vehicle, determined by the processor, with respect to each RF-transmitting antenna from which RF signals are received.
19. A method of controlling a vehicle comprising:
receiving, by at least three spatially separated receiver antennae coupled to the vehicle, radio frequency (RF) signals from one or more RF-transmitting antennae coupled to an object;
determining timing information from the received RF signals;
storing information related to fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae;
determining a relative position of the vehicle with respect to the one or more RF-transmitting antennae based on the stored information related to the fixed distances between each receiver antenna and each other receiver antenna of the at least three spatially separated receiver antennae and on the determined timing information determined; and
controlling operation of the vehicle in response to the determined relative position of the vehicle with respect to the one or more RF-transmitting antennae.