JPH0527005A - Position detecting method - Google Patents

Abstract

PURPOSE:To obtain correct positional information on a receiver side by calculating the data to indicate the error between the known positional information and the measured positional information, and broadcasting the error data. CONSTITUTION:A GPS receiver 101 provided in a broadcasting station obtains the respective positional data 102,103,104 in terms of the latitude, the longitude and the altitude. These data include errors caused by the tracking errors, the effects of the ionized layer or the like, or the intentional errors. Thus, the errors are calculated in an error calculating part 105 by using these data and the correct position, and the error data 106, 107, 108 corresponding to the respective data are obtained. Then, these data are for example, packeted at a packeting part 110 together with measuring time data 109. The packeted error data are received by an FM multiplexing device 112 together with other data 111 for the FM multiflexed broadcasting use, and broadcasted. Other GPS receivers located in other positions realize correction of the positional data by using the error data transmitted by the broadcasting station.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to GPS (Global Position
ionization system) to measure the current position on the earth.

More specifically, the present invention can be applied to GPS receivers, FM multiplex receivers, and data broadcast receivers.
The present invention relates to a position detection method. The present invention also relates to a position detecting method applicable to a car navigation system or a portable position measuring receiver.

[0003]

SUMMARY OF THE INVENTION The present invention is a GPS (Global Positioning)
When measuring the position using the (System), if there are orbital errors, measurement errors caused by the effects of the ionosphere, or intentionally sending incorrect data, etc. By receiving and calculating the signal and providing the correction information to the receiver by data broadcasting such as FM multiplex broadcasting, an accurate position can be measured.

[0004]

2. Description of the Related Art Conventionally, there is a GPS receiver as a receiver for measuring the position on the earth. However, an error of several tens to several hundreds of meters occurs due to an orbital error and the influence of the ionosphere. In addition, it is possible to intentionally make data erroneous for various reasons to transmit a signal from a GPS satellite.

As another position detecting method, there is a position detecting system using a pilot signal of FM broadcasting. This is to receive three or more FM stations and obtain the position from the phase difference of the pilot signals. In this system, terrestrial broadcast waves are used and signals outside the service area are also used originally, so errors of several hundred meters to several kilometers occur due to multipath distortion.

[0006]

As described above, in the conventionally known position detecting method, a certain amount of error is always included in the position measurement.

Therefore, an object of the present invention is to send error information by data broadcasting such as FM multiplex broadcasting in order to reduce such measurement error and correct the result obtained by the conventional method at the receiver side. It is to provide a position detection method capable of obtaining accurate position information.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a position detecting method for detecting a position on the earth by receiving a radio wave from a satellite, by a radio wave received from the satellite at a receiving station having known position information. It is characterized in that measurement position information is obtained, error data representing an error between the known position information and the measurement position information is calculated, and the error data is broadcast.

Further, according to the present invention, when receiving a radio wave from a satellite to measure the current position, an error included in the position measurement data by the satellite is received by a predetermined data broadcast and measured at the measurement point. The present position is corrected by the calculated position data and the error amount.

[0010]

In the present invention, the GPS (Global Positioning System)
tem) to measure the position using the orbit error, the measurement error caused by the influence of the ionosphere, or when intentionally sending incorrect data, etc. Receives the signal, calculates it,
The correction information is provided to the receiver by data broadcasting such as FM multiplex broadcasting.

[0011]

EXAMPLES Examples of the present invention will be described in detail below.

FIG. 1 shows the configuration of the transmission side of a position error transmission system according to an embodiment of the present invention. Here 101 is the existing G
It is a PS receiver and can measure latitude and longitude by receiving three GPS satellites, and can measure latitude, longitude and altitude by receiving four or more GPS satellites.

Reference numerals 102, 103, and 104 are position data when the receiver 101 is installed in a broadcasting station. This data is tens to hundreds of meters due to orbital errors and the influence of the ionosphere.
There is an error of. In some cases, the data error is intentionally increased.

The error calculation unit 105 calculates an error from the data including the error and the accurate position of the broadcasting station, and the error data 106, 107 of latitude, longitude, and altitude,
108 is obtained, and is packetized together with the measured time data 109 in the packetizing unit 110.

The example of FIG. 1 is a case where FM multiplex broadcasting suitable for mobile reception is used as data broadcasting.

The error data packetized by the packetizing unit 110 is input to the FM multiplexer 112 together with other data 111 for FM multiplex broadcasting, and is broadcast. Of course,
It may be sent without packetization.

FIG. 2 shows a position detection receiver according to an embodiment of the present invention. Here, the GPS receiver 201 is an existing G
It is a PS receiver. Reference numeral 202 denotes an FM multiplex receiver, and the data separation unit 209 separates only the error data 208.

Reference numerals 203, 204, and 205 are each data of latitude, longitude, and altitude, but have errors as described above. These data are corrected in the error correction unit 207 by the error data sent from the broadcasting station (see FIG. 1).

The error in the GPS receiver 201 is due to the orbital error and the ionosphere, and can be considered to be almost constant in the FM broadcast service area. The output data 211, 212, 213 of the error correction unit 207 is quite accurate. It becomes high position information.

In the above-mentioned embodiments, FM multiplexing has been described as an example, but it is needless to say that the same effect as the present invention can be exhibited by using other data broadcasting.

[0021]

In the conventional GPS receiver, the number of satellites to be received is increased in order to increase the accuracy of position measurement, but the error still remains. It is also possible that the data is intentionally transmitted with an error.

Therefore, by using the present invention, it is possible to measure the position with extremely high accuracy if only the required minimum number of satellites can be received.

On the other hand, the FM multiplex receiver is low in cost because data can be obtained by taking out a frequency-multiplexed signal for FM broadcasting.

Since an automobile equipped with a GPS receiver is equipped with an FM receiver, the cost for implementing the present invention is small.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a transmission side of a position error transmission system according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a position detection receiver according to an embodiment of the present invention.

[Explanation of symbols]

101 GPS receiver 105 Error calculator 110 Packetization unit 112 FM multiplexer 113 FM multiple modulator 115 FM broadcaster 201 GPS receiver 202 FM multiplex receiver 207 Error correction unit 209 Data separation unit

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shigeki Moriyama             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Sending Association Broadcasting Technology Research Institute (72) Inventor Tomohiro Saito             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Sending Association Broadcasting Technology Research Institute (72) Inventor, Yamada             1-10-11 Kinuta, Setagaya-ku, Tokyo, Japan             Sending Association Broadcasting Technology Research Institute

Claims (3)

[Claims] 1. A position detecting method for receiving a radio wave from a satellite to detect a position on the earth, wherein a receiving station having known position information obtains measurement position information by a radio wave received from the satellite, A position detection method characterized by calculating error data representing an error between the position information and the measured position information, and broadcasting the error data. 2. The error data according to claim 1, wherein
Position detection method characterized by broadcasting by M multiplex broadcasting. 3. A position measured at a measurement point by receiving an error component included in position measurement data by the satellite when receiving a radio wave from the satellite and measuring the current position by a predetermined data broadcast. A position detection method characterized in that the current position is corrected based on the data and the error.