Location detection method, location detection system and location detection program
First Claim
1. A positioning method of calculating a position of a receiver according to propagation delay time of signals from a plurality of wireless transmitters, comprising:
- a first step of detecting a signal from each of the wireless transmitters, obtaining a position of each of the wireless transmitters from which the signal is detected, measuring propagation delay time of the signal from each of the wireless transmitters, and calculating a position of the receiver and a standard deviation about measuring distance error associated with the measurement of the propagation delay time;
a second step of calculating a positioning error of the receiver according to the position of each of the wireless transmitters and the position of the receiver and the standard deviation calculated in said first step;
a third step of determining, according to the positioning error of the receiver calculated in said second step, wireless transmitters in directions nearer to a direction in which the positioning error is large; and
a fourth step of re-detecting signals from the wireless transmitters in directions nearer to a direction in which the positioning error is large determined in said third step and thereby re-calculating the position of the receiver.
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Accused Products
Abstract
A positioning method, which is related to a technique to measure a correct position of a terminal by preventing time required for the position measurement, of calculating a position of a receiver according to signals from a plurality of wireless transmitters includes a first step of measuring propagation delay time of the signal from each of the wireless transmitters and calculating a position of the receiver and a standard deviation about measuring distance error, a second step of calculating a positioning error of the receiver a third step of determining, according to the positioning error calculated by the second step, wireless transmitters in directions nearer to a direction in which the positioning error is large, and a fourth step of re-detecting signals from the wireless transmitters determined by the third step and thereby re-calculating the position of the receiver.
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Citations
13 Claims
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1. A positioning method of calculating a position of a receiver according to propagation delay time of signals from a plurality of wireless transmitters, comprising:
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a first step of detecting a signal from each of the wireless transmitters, obtaining a position of each of the wireless transmitters from which the signal is detected, measuring propagation delay time of the signal from each of the wireless transmitters, and calculating a position of the receiver and a standard deviation about measuring distance error associated with the measurement of the propagation delay time;
a second step of calculating a positioning error of the receiver according to the position of each of the wireless transmitters and the position of the receiver and the standard deviation calculated in said first step;
a third step of determining, according to the positioning error of the receiver calculated in said second step, wireless transmitters in directions nearer to a direction in which the positioning error is large; and
a fourth step of re-detecting signals from the wireless transmitters in directions nearer to a direction in which the positioning error is large determined in said third step and thereby re-calculating the position of the receiver. - View Dependent Claims (2, 3)
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4. A positioning method of calculating a position of a receiver according to propagation delay time of signals from a plurality of wireless transmitters, comprising:
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a first step of detecting a signal from each wireless transmitter, obtaining a position of each wireless transmitter from which the signal is detected, measuring propagation delay time of the signal from said each wireless transmitter, and calculating a position of the receiver and a standard deviation about measuring distance error associated with the measurement of the propagation delay time;
a second step of calculating a positioning error of the receiver according to the position of each wireless transmitter and the position of the receiver and the standard deviation calculated in said first step;
a third step of determining, according to the positioning error of the receiver calculated in said second step, wireless transmitters in directions nearer to a direction in which the positioning error is large; and
a step of calculating a positioning error of the receiver at re-detection of a signal from each of the wireless transmitters in directions nearer to a direction in which the positioning error is large determined in said third step and thereby calculating a required number of re-detection to re-detect signals from each of the wireless transmitters in directions nearer to a direction in which the positioning error is large; and
re-calculating the position of the receiver according to each propagation delay time measured by re-detecting a signal from each of the wireless transmitters as many times as indicated by the required number of re-detection, each standard deviation about measuring distance error associated with the measurement of the propagation delay time, the propagation delay time of each said wireless terminal measured before the re-detection, the standard deviation calculated before the re-detection, and the position of each said wireless transmitter. - View Dependent Claims (5)
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6. A positioning system for calculating a position of a receiver according to propagation delay time of signals from a plurality of wireless transmitters, comprising:
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a receiver unit for receiving a signal from each of said wireless transmitters;
a delay profile generator for generating a delay profile of a signal from said each wireless transmitter and for outputting the delay profile;
a propagation time measurement unit for analyzing the delay profile and for thereby measuring propagation delay time of the signal;
a storage unit for storing data required to calculate a position of the positioning system; and
a processing unit for controlling said receiver unit, said delay profile generator, said propagation time measurement unit, and said storage unit for processing various data used to calculate the position and for thereby conducting a positioning operation, wherein said processing unit comprises;
position calculating means for obtaining a position of said positioning system according to the propagation delay time measured by said propagation time measurement unit;
standard deviation calculating means for calculating a standard deviation about measuring distance error associated with the measurement of the propagation delay time; and
error calculating means for calculating a positioning error of said positioning system according to the position of each of said wireless transmitters, the position of said positioning system calculated by said position calculating means, and the standard deviation calculated by said standard deviation calculating means. - View Dependent Claims (7, 8, 9, 10)
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11. A position information supplying method for use with a position information supplying system comprising a handset including a positioning unit for calculating a position according to propagation delay time of signals from a plurality of wireless transmitters and a position information recognizing unit for supplying the position calculated by the positioning unit, in a format recognizable by a user, wherein:
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the positioning unit determines wireless transmitters in directions nearer to a direction in which the positioning error is large, re-detecting signals from the wireless transmitters in directions nearer to a direction in which the positioning error is large, re-calculating the position of the handset, and outputting information of the position to a communication network; and
the position information recognizing unit receives a result of the positioning operation received from the positioning unit via the communication network, generating information recognizable by a user by combining the result of the positioning operation with map information corresponding thereto, and outputting the information. - View Dependent Claims (12, 13)
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Specification