JPS5824873A - Measuring apparatus for radio wave receiving position - Google Patents

Abstract

PURPOSE:To enable accurate determination of receiving position by solving proper equation derived from an observation equation in the number equal to that of unknown values therein. CONSTITUTION:Radio waves are received from a wireless navigation aid system adapted to emit radio waves synchronized in a fixed relationship. The received phase of the radio waves is measured with respect to an appropriate reference signal. Based on a plurality of measured data and the reception positions, an observation equation is set up to connect the true direction of the station corresponding to the data, a deviation between an estimated receiving position and the actual receiving position and the phase of the reference signal. Then, from this observation equation, proper equations are derived in the number equal to that of unknown values therein. Then, the equations thus obtained are solved to find the correct receiving position. This enables the expansion of the service area free from error due to possible drift of the reference signal without causing difficulty in measuring the position. A higher stability of the measured values can be obtained in a short time.

Description

DETAILED DESCRIPTION OF THE INVENTION For example, the data measured by a hyperbolic navigation receiver using the Loran-C System 1M, a radio navigation aid system operated by the US Coast Guard, is as follows.

This is the relative arrival time difference between the radio waves emitted by the slave station and the radio waves emitted by the master station at the receiving point. Let this data be TD.

5bz where (sr, +cD) 1: Launch delay time τ of slave station [
E: Radio wave propagation time from the slave station to the receiving point T□E: General time for radio wave propagation from the master station to the receiving point.

From this data, consider knowing the geodetic coordinates (q)i)c) of the receiving point.

Given the estimated receiving position of the receiving point, and from this and the position of the radio wave emitting station given in advance as a system constant, calculate the geodesic length between the transmitting and receiving points and find the radio wave propagation time τlt.
In addition, calculate the true bearing of each station z1゜2, ...Zj as seen from the estimated receiving position.

The known numbers ΔTi, , Zi obtained from these calculations and the latitude and longitude deviation Δ between the estimated reception position and the actual reception position, which are unknown numbers, are entered.

The observation equation that connects △ψ and the reception phase of the main station's radio waves is:

It is.

The known constants of this observation equation are calculated using the method of least squares, and a number of normal equations equal to the number of unknowns are derived (,
(For that, 0osZ+, 5inZH, T in equation (3))
The corollary number 1゜ΔJ of c is aL +bf tOjs, respectively
When dL, U at atl [bt aL]
, [0tail, [di 'J] + [:bl
1)+:], [O+tl+].

[d) Calculate tli, [C+O+, [dHc;]. From this calculated value, we can find the most probable value of the unknown. Once we have reached this point, we can find the solution to the unknown completely mechanically from the determinant of the system. , all unknowns have been determined. The reception position to be determined has been described above as the positioning principle of the present invention, but the features of the positioning apparatus that performs such data processing compared to the conventional system will be listed here.

(+) (3)I Since (4) is solved with Tχ as an unknown, the reference signal that is the standard for measurement is not the receiving phase of the main station's radio waves as in this example, but the distance navigation (f'
(also called P-navigation), exactly the same solution can be obtained even on a measurement day or evening for an appropriate reference signal at the receiving point.

Moreover, this was a drawback of conventional distance navigation. It is not affected by the L difference caused by the drift of the reference signal.

(2) Receive radio waves from three stations and obtain two hyperbolic data. In hyperbolic navigation, positioning is difficult near the extension line of the baseline connecting the master and slave stations, but with this method, radio waves from three stations are received,
Three pieces of data can be obtained via the reference signal, and regardless of the geometrical quantity system between the transmitting and receiving points, as long as the three pieces of data can be obtained, the problem of >111 will not occur and the service area will be widened.

(3) If the system is composed of 5 stations, a maximum of 5 pieces of data can be acquired, and all of them can be incorporated into positioning calculations, which improves the short-term stability of way-dumpling positioning values when positioning one data. can be expected to improve.

(4) In this method, when there is a large amount of received data, the quality of the data can be evaluated by subtracting the T value obtained by calculating the final positioning value from the individual measurement data △T. Yes, I can.

This Vl is usually called a residual, and has the property of being zero if there is no error in the measurement data. (5) vl
is at a known point, then V at this time.

Claims (1)

[Claims] "Radio waves from a radio navigation aid system that emits radio waves synchronized in a certain relationship are received, and the reception phase of these radio waves is measured with respect to an appropriate reference signal. A plurality of measurement data and reception positions. An observation equation is created that connects the true direction of the station corresponding to the data, the longitude and latitude deviation between the estimated reception position and a certain reception position, and the phase of the reference signal, and from this observation equation, a number equal to the number of unknowns is calculated. A radio wave receiving side positioning device that derives the normal equation of and determines the receiving position by solving this equation.