System and method for enhancing the accuracy of a location estimate
First Claim
1. A method for estimating the geo-location of a wireless transmitter emitting a signal that is received by a plurality of sensors in a geo-location system which further includes a geo-location estimation device which provides an overdetermined geo-location solution for the wireless transmitter, comprising the steps of:
- (a) at the sensors;
(i) measuring an attribute of the emitted signal to thereby create a sensor signal; and
(ii) sending the sensor signal to the geo-location estimation device;
(b) at the geo-location estimation device;
(i) receiving the plural sensor signals;
(ii) associating with each sensor signal a separate initial predetermined weight value to thereby provide a plurality of initial estimation signals;
(iii) determining an initial estimate of the geo-location of the wireless transmitter from the initial estimation signals;
(iv) modifying the weight value associated with the dominant sensor signals relative to the weight value associated with the non-dominant sensor signals to thereby provide a plurality of refined estimation signals;
(v) determining a refined estimate of the geo-location of the wireless transmitter from the refined estimation signals;
(vi) repeating steps (b)(iv) through (b)(v) a predetermined number of times to thereby estimate the geo-location of the wireless transmitter.
16 Assignments
0 Petitions
Accused Products
Abstract
A method for enabling a system to enhance the accuracy of a location estimate modifies weights in a weight matrix associated with receiver station measurements in parallel with successive refinements of the location estimate. In a typical location estimation scenario, several receiving stations simultaneously derive measurements of a signal from the emitter. Any one of these measurements is in general some function of the emitter location and the receiving station location. The aggregate of these measurements is often in excess of the minimum number of measurements required to provide an estimate of the emitter location. Where such an excess exists, the method proceeds by modifying the weights associated with the measurements in parallel with successive refinements of the location estimate. The method can be implemented over various cellular protocols with a consistent and significant enhancement in the accuracy of location estimates.
-
Citations
51 Claims
-
1. A method for estimating the geo-location of a wireless transmitter emitting a signal that is received by a plurality of sensors in a geo-location system which further includes a geo-location estimation device which provides an overdetermined geo-location solution for the wireless transmitter, comprising the steps of:
-
(a) at the sensors; (i) measuring an attribute of the emitted signal to thereby create a sensor signal; and (ii) sending the sensor signal to the geo-location estimation device; (b) at the geo-location estimation device; (i) receiving the plural sensor signals; (ii) associating with each sensor signal a separate initial predetermined weight value to thereby provide a plurality of initial estimation signals; (iii) determining an initial estimate of the geo-location of the wireless transmitter from the initial estimation signals; (iv) modifying the weight value associated with the dominant sensor signals relative to the weight value associated with the non-dominant sensor signals to thereby provide a plurality of refined estimation signals; (v) determining a refined estimate of the geo-location of the wireless transmitter from the refined estimation signals; (vi) repeating steps (b)(iv) through (b)(v) a predetermined number of times to thereby estimate the geo-location of the wireless transmitter. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 51)
-
-
11. A method for estimating the geo-location of a wireless transmitter emitting a signal that is received by a plurality of sensors in a geo-location system which further includes a geo-location estimation device which provides an overdetermined geo-location solution for the wireless transmitter, comprising the steps of:
-
(a) providing a sensor signal for each of the plurality of sensors as a function of an attribute of the received signal at the respective sensor; (b) providing an initial weight value for each sensor signal; (c) estimating the initial geo-location of the wireless transmitter as a function of the sensor signals and the respective initial weight values; (d) determining the offset of each sensor signal from the estimated initial geo-location; (e) updating the weight value for at least one of the sensor signals as a function of the offset for the respective sensor signal; (f) estimating the updated geo-location of the wireless transmitter as a function of the sensor signals and the respective updated weight values; (g) determining the offset of each sensor signal from the updated geo-location; (h) repeating steps (e) through (g) a predetermined number of times to thereby estimate the geo-location of the wireless transmitter. - View Dependent Claims (12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 50)
-
-
24. A method for estimating the geo-location of a wireless transmitter emitting a signal that is received by a plurality of sensors in a geo-location system which further includes a geo-location estimation device which provides an overdetermined geo-location solution for the wireless transmitter as a function of sensor signals determined from an attribute of the received signal at the plurality of sensors, comprising the steps of:
-
(a) assigning a weight value for each sensor signal; (b) estimating the geo-location of the wireless transmitter as a function of the sensor signals and the weight values assigned to the sensor signals; (c) determining the offset of each received signal from the estimated geo-location; (d) updating the weight value for at least one of the sensor signals as a function of the. offset for the respective sensor signal; (e) repeating steps (b) through (d) a predetermined number of times to thereby estimate the geo-location of the wireless transmitter. - View Dependent Claims (25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36)
-
-
37. A system for estimating the geo-location of a wireless transmitter emitting a signal that is received by a plurality of sensors in a geo-location system which further includes a geo-location estimation device which provides an overdetermined geo-location solution for the wireless transmitter as a function of sensor signals determined from an attribute of the received signal at the plurality of sensors, comprising:
-
(a) means for assigning a weight value for each sensor signal; (b) means for estimating the geo-location of the wireless transmitter as a function of the sensor signals and the weight values assigned to the sensor signals; (c) means for determining the offset of each received signal from the estimated geo-location; (d) means for updating the weight value for at least one of the sensor signals as a function of the offset for the respective sensor signal; (e) means for repeating steps (b) through (d) a predetermined number of times to thereby estimate the geo-location of the wireless transmitter. - View Dependent Claims (38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49)
-
Specification