Systems and methods for using doppler measurements to estimate a position of a receiver
Estimating the position of a receiver using positioning signals and Doppler frequency measurements. Approaches for estimating the position of a receiver using positioning signals and Doppler frequency shift measurements determine an initial estimate of a receiver's position using ranging signals from a first system, generate Doppler frequency shift measurements using the Doppler positioning signals from a second system, and refine the initial estimate using the Doppler frequency shift measurements.
1. A method for estimating a position of a receiver, the method comprising:
receiving, at the receiver, first positioning signals from transmitters of a first network;
receiving, at the receiver, second signals from transmitters of a second network;
generating Doppler frequency shift measurements using the second signals; and
determining an estimated position of the receiver using the first positioning signals and the Doppler frequency shift measurements by:
(i) initializing a Particle Filter;
(ii) generating a plurality of particles and respective weights, wherein each particle represents a hypothesis of the position of the receiver, and wherein each respective weight represents a probability that the hypothesis of the respective particle is closest to the position of the receiver;
(iii) updating each of the respective weights using the first positioning signals;
(iv) generating, for each of the plurality of particles, a likelihood value that represents a probability that the hypothesis of the particle is closest to the position of the receiver given the Doppler frequency shift measurements; and
(v) updating each respective weight using the likelihood value generated for its respective particle.
2. The method of claim 1 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km.
3. The method of claim 1 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more non-orbiting aerial vehicles.
4. The method of claim 1 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more low earth orbit (LEO) satellites.
5. The method of claim 1 , wherein the transmitters of the first network include Global Positioning System (GPS) satellites, and wherein the transmitters of the second network include one or more non-GPS satellites.
6. The method of claim 1 , wherein the receiver receives the first positioning signals from the transmitters of the first network when the receiver is in a first region, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network when the receiver is in a second region;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
7. The method of claim 1 , wherein the receiver receives the first positioning signals from the transmitters of the first network during a first time period, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network during a second time period;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
8. A method for estimating a position of a receiver, the method comprising:
receiving, at the receiver, first positioning signals from transmitters of a first network;
receiving, at the receiver, second signals from transmitters of a second network;
generating Doppler frequency shift measurements using the second signals; and
determining an estimated position of the receiver using the first positioning signals and the Doppler frequency shift measurements by:
(i) generating, using the first positioning signals, a first error surface that represents a search space for the receiver;
(ii) generating, for each point on the first error surface, a likelihood value corresponding to the probability of that point comprising the true position of the receiver given the Doppler frequency shift measurements;
(iii) generating a second error surface by modifying the value at each point of the first error surface using the generated likelihood value for that point; and
(iv) determining the estimated position of the receiver using the second error surface.
9. The method of claim 8 , wherein the estimated position of the receiver is determined by finding a region of minimum value on the second error surface and determining the estimated position of the receiver using the region of minimum value.
10. The method of claim 8 , wherein the second error surface is generated by multiplying the value at each point of the first error surface by the likelihood value for that point.
11. The method of claim 8 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km.
12. The method of claim 8 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more non-orbiting aerial vehicles.
13. The method of claim 8 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more low earth orbit (LEO) satellites.
14. The method of claim 8 , wherein the transmitters of the first network include Global Positioning System (GPS) satellites, and wherein the transmitters of the second network include one or more non-GPS satellites.
15. The method of claim 8 , wherein the receiver receives the first positioning signals from the transmitters of the first network when the receiver is in a first region, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network when the receiver is in a second region;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
16. The method of claim 8 , wherein the receiver receives the first positioning signals from the transmitters of the first network during a first time period, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network during a second time period;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
17. One or more non-transitory machine-readable media embodying program instructions that, when executed by one or more machines, cause the one or more machines to perform a method for estimating a position of a receiver, the method comprising:
receiving, at the receiver, first positioning signals from transmitters of a first network;
receiving, at the receiver, second signals from transmitters of a second network;
generating Doppler frequency shift measurements using the second signals; and
determining an estimated position of the receiver using the first positioning signals and the Doppler frequency shift measurements by:
(i) initializing a Particle Filter;
(ii) generating a plurality of particles and respective weights, wherein each particle represents a hypothesis of the position of the receiver, and wherein each respective weight represents a probability that the hypothesis of the respective particle is closest to the position of the receiver;
(iii) updating each of the respective weights using the first positioning signals;
(iv) generating, for each of the plurality of particles, a likelihood value that represents a probability that the hypothesis of the particle is closest to the position of the receiver given the Doppler frequency shift measurements; and
(v) updating each respective weight using the likelihood value generated for its respective particle.
18. The one or more non-transitory machine-readable media of claim 17 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km.
19. The one or more non-transitory machine-readable media of claim 17 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more non-orbiting aerial vehicles.
20. The one or more non-transitory machine-readable media of claim 17 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more low earth orbit (LEO) satellites.
21. The one or more non-transitory machine-readable media of claim 17 , wherein the transmitters of the first network include Global Positioning System (GPS) satellites, and wherein the transmitters of the second network include one or more non-GPS satellites.
22. The one or more non-transitory machine-readable media of claim 17 , wherein the receiver receives the first positioning signals from the transmitters of the first network when the receiver is in a first region, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network when the receiver is in a second region;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
23. The one or more non-transitory machine-readable media of claim 17 , wherein the receiver receives the first positioning signals from the transmitters of the first network during a first time period, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network during a second time period;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
24. One or more non-transitory machine-readable media embodying program instructions that, when executed by one or more machines, cause the one or more machines to perform a method for estimating a position of a receiver, the method comprising:
receiving, at the receiver, first positioning signals from transmitters of a first network;
receiving, at the receiver, second signals from transmitters of a second network;
generating Doppler frequency shift measurements using the second signals; and
determining an estimated position of the receiver using the first positioning signals and the Doppler frequency shift measurements by:
(i) generating, using the first positioning signals, a first error surface that represents a search space for the receiver;
(ii) generating, for each point on the first error surface, a likelihood value corresponding to the probability of that point comprising the true position of the receiver given the Doppler frequency shift measurements;
(iii) generating a second error surface by modifying the value at each point of the first error surface using the generated likelihood value for that point; and
(iv) determining the estimated position of the receiver using the second error surface.
25. The one or more non-transitory machine-readable media of claim 24 , wherein the estimated position of the receiver is determined by finding a region of minimum value on the second error surface and determining the estimated position of the receiver using the region of minimum value.
26. The one or more non-transitory machine-readable media of claim 24 , wherein the second error surface is generated by multiplying the value at each point of the first error surface by the likelihood value for that point.
27. The one or more non-transitory machine-readable media of claim 24 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km.
28. The one or more non-transitory machine-readable media of claim 24 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more non-orbiting aerial vehicles.
29. The one or more non-transitory machine-readable media of claim 24 , wherein the transmitters of the first network are included in one or more of a Global Navigation Satellite System (GNSS), a terrestrial navigation system, a wireless cellular network, or a network of wireless access points, and wherein the transmitters of the second network include one or more low earth orbit (LEO) satellites.
30. The one or more non-transitory machine-readable media of claim 24 , wherein the transmitters of the first network include Global Positioning System (GPS) satellites, and wherein the transmitters of the second network include one or more non-GPS satellites.
31. The one or more non-transitory machine-readable media of claim 24 , wherein the receiver receives the first positioning signals from the transmitters of the first network when the receiver is in a first region, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network when the receiver is in a second region;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.
32. The one or more non-transitory machine-readable media of claim 24 , wherein the receiver receives the first positioning signals from the transmitters of the first network during a first time period, the method further comprising:
receiving, at the receiver, third positioning signals from transmitters of a third network during a second time period;
receiving, at the receiver, additional signals from the transmitters of the second network;
generating additional Doppler frequency shift measurements using the additional signals; and
determining another estimated position of the receiver using the third positioning signals and the additional Doppler frequency shift measurements,
wherein the transmitters of the second network include one or more orbiting satellite vehicles with an orbital height of less than 15,000 km, one or more low earth orbit (LEO) satellites, or one or more non-orbiting aerial vehicles, and
wherein (a) the first network is a terrestrial navigation system and the third network is a Global Navigation Satellite System (GNSS), (b) the first network is the terrestrial navigation system and the third network is a wireless cellular network, or (c) the first network is the wireless cellular network and the third network is the GNSS.