JPH08278360A - Position measuring system - Google Patents

Abstract

PURPOSE: To attain an accurate correcting processing by converting a correction data extracted from a multidata into an RTCM1 type correction data in correspondance with a satellite orbit information extracted from a satellite signal and correcting a measuring information based on the correction data. CONSTITUTION: An orbit data IODE of a receiving satellite received by a D GPS receiver 43 is extracted by a GPS.IOD extracting part 40 in a DARC to RTCM convertor 34 and the result is given to a differential correction computation part 39. In addition, a psuedo distance correction value PRC and distance change rate correction value RRC are sent to the part 39 through a differential data extracting part 35, PRC extracting part 36 and RRC extracting part 37. The part 39 calculated a differential correction value with an RTCM1 type format based on them and gives the result to a differential data CPU 46 so as to correct the measured position of a position measuring CPU 45. Thus an accurate correction can be made at all times.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention determines the position of a moving body such as an automobile, a ship or an aircraft based on a signal received directly from a plurality of satellites and a correction signal received from a fixed reference station. The present invention relates to a positioning method using a differential GPS (Global Positioning System) that measures and outputs with high accuracy.

[0002]

2. Description of the Related Art Conventionally, in a moving body such as an automobile, a ship, and an aircraft, a GPS has been put into practical use which measures and outputs the position of the moving body based on signals directly received from a plurality of satellites.

That is, the GPS calculates pseudo distances from the respective satellites based on signals received from a plurality of satellites, and the moving position (latitude, longitude) of the moving body on the earth.
Thus, for example, in a car navigation device using GPS, the moving position of the vehicle is displayed on a road map.

However, in the GPS, the signal received from each satellite may include, for example, an ionospheric delay error or a troposphere delay error that changes the signal arrival time.
Since various error factors are included, errors will inevitably occur in the moving position measured based on the satellite signal including these error factors.

Therefore, in a fixed reference station whose exact position on the earth is known beforehand, the position of the reference station is measured by the GPS, and a correction signal is created according to the difference between the measured position and the position of the previously mentioned reference station. , For example, by transmitting as FM multiplex broadcasting, the mobile unit receives a plurality of satellite signals and measures their moving positions, and the measured moving positions are multiplexed and received as the FM broadcasting. A differential-type GPS, that is, D-GPS, has been considered in which a moving position of a moving body is obtained with extremely high accuracy by performing correction according to a correction signal.

FIG. 4 is a diagram showing the overall configuration of a differential GPS using FM multiplex broadcasting.

First, in the D / GPS fixed reference station 11 whose exact position on the earth is known in advance, a plurality of GPS satellites 1
The signals from 2a, 12b, ... Are received, the reference station position is measured based on the satellite signals, and correction value data is created according to the difference between the reference station position measured by this GPS satellite and a known accurate reference station position. To do.

The correction value data created by the D / GPS fixed reference station 11 is the FM multiplex DARC data control unit 1.
In 3, the DARC "trademark" (Data Radio Channel)
It is formatted according to the transmission format of the system.

FIG. 5 is a diagram showing the structure of a DARC transmission frame multiplexed in FM broadcasting.

This DARC transmission frame has 272 blocks of packets transmitted at 5 (SEC) per frame, of which two data packets are assigned as transmission packets.

FIG. 6 is a diagram showing the contents of D / GPS data assigned to the two packets of the DARC transmission frame.

The D / GPS data assigned to the two packets of the DARC transmission frame includes, for example, eight GPS satellites 12 after the data identification number ID.
A correction data set corresponding to each satellite obtained based on the received signals from a, 12b, ... And communication data indicating normality / abnormality of each satellite are given.

FIG. 7 is a view showing the contents of the correction data set of each satellite given as the D / GPS data.

That is, for example, as a correction data set corresponding to each of the satellite 1 to the satellite 8, the scale factor (S) of the pseudo range correction value (PRC) is set.
F), user differential distance error index (User
Differential Range Error: UDER, Satellite ID: St. ID, Pseudorange Correction: PRC, Range Change Correction: RRC, Satellite Orbit Data Issue number (Issue Of Data: IO
DE) is given.

In this way, in the FM multiplex DARC data control unit 13, the correction data corresponding to each of the eight GPS satellites 12a, 12b, ... In the FM voice (music) signal is multiplexed and modulated by frequency division, and is transmitted from the transmitter 15 of the FM station via the transmitting antenna 16 to the FM multiplex DAR.
It is transmitted as a C system broadcast signal.

On the other hand, in the D / GPS receiver 18 mounted on the moving body 17 such as an automobile, the plurality of GPS satellites 1
2a, 12b, ... Receives signals from each satellite 12a,
.., and the moving position of the moving body 17 is measured based on the calculated pseudo distances to the satellites 12a, 12b ,.

Further, the FM multiplex receiver 19 mounted on the mobile unit 17 receives the broadcast signal of the FM multiplex DARC system and the DA multiplexed with the broadcast signal.
The correction value data in the RC format is extracted and converted into a data format standardized by RTCM (Marine Radio Technical Committee), and the D / GPS receiver 1 is used.
Supply to 8.

As a result, the D / GPS receiver 18
Then, based on the correction value data obtained in the RTCM standardized format, the moving position of the moving body 17 measured by the D / GPS receiver 18 is corrected, and highly accurate position measurement can be achieved.

FIG. 8 shows a D / GPS receiver 18 and an FM multiplex receiver 19 mounted on a conventional D / GPS mobile unit.
FIG. 3 is a block diagram showing the configuration of FIG.

In the moving body 17, the transmitting antenna 1
The FM multiplex DARC system broadcast signal transmitted from
When it is received by the FM tuner 22 via the FM antenna 21, the FM multiplex signal received by the FM tuner 22 is separated by the FM multiplex decoder 23 into an FM voice (music) signal and DARC format data, and the D
The ARC format data is given to the DARC → RTCM converter 24.

FIG. 9 is a diagram showing a conversion state of correction value data (PRC, RRC) by the DARC → RTCM converter 24 of the FM multiplex receiver 19 mounted on the conventional D / GPS mobile unit.

In this case, in FIG. 9, the pseudo range correction value (PRC) and the range change rate correction value (RRC) for a certain GPS satellite are received and demodulated as DARC format data for every fixed time (5 seconds). , Sequentially corresponding R
An example of conversion into TCM format data is shown.

Further, (100) and (10 in FIG.
1) indicates satellite orbit data (IODE), for example, P
RC1 (100) and RRC1 (100) indicate the pseudo range correction value (PRC) and the range change rate correction value (RRC) at time "1" in satellite orbit "100", respectively.

Here, in the correction value data in the DARC format, when the satellite orbit (IODE) is updated, the correction value data based on the new satellite orbit and the correction value data based on the old satellite orbit are shown in FIG. FM multiple DA shown in
The RC data control unit 13 alternately exchanges the data for several minutes (5 to 6 minutes) and sends the data.

That is, for example, D and G in FIG.
GPS satellites 12 received by the PS fixed reference station 11
When the trajectory of a is updated between time (3) and time (4), it is received and demodulated by the FM multiplex receiver 19 of the mobile unit 17 and given to the DARC → RTCM converter 24.
The pseudo distance correction value (PRC) and the distance change rate correction value (RRC) of the C format data are PRC1 (100) and RRC1 (100) until the time (3) before the trajectory update.
→ PRC2 (100), RRC2 (100) → PRC3
(100), RRC3 (100), and PRC4 (101), R after the time (4) after the orbit update.
RC4 (101) → PRC5 (100), RRC5 (1
00) → PRC6 (101), RRC6 (101) and old and new are exchanged and given.

In this case, in the DARC → RTCM converter 24, in the RTCM type 1 format, the correction values (PRC, RRC) of the DARC format are PRC3 (100), RRC from time (3) to time (4).
3 (100) to PRC4 (101), RRC4 (10
After the change to 1), after the same time (4),
The RTCM differential correction values PRC (101) and RRC (10 corresponding to the updated orbit data “101”
1) is sequentially generated and the GPS of the D / GPS receiver 18 is generated.
Given to the tuner 26.

That is, when the orbit data (IODE) in the DARC format is updated according to the orbit update of the receiving satellite in the fixed reference station 11, the DARC → RTCM converter 24 to D of the FM multiplex receiver 19 mounted on the mobile unit 17 is updated.・ GPS tuner 18 of GPS receiver 18
The differential correction value in the RTCM format given to the above is also switched to the correction value after the trajectory update.

However, the fixed reference station 11 is GP
In the installation environment suitable for receiving signals from the S satellites 12a, 12b, ...
In comparison with the above, since there is a very unfavorable moving environment for receiving signals from the GPS satellites 12a, 12b, ... There is a case where the orbits of the receiving satellites in the fixed reference station 11 are updated to new orbits, but the orbits of the receiving satellites in the mobile unit 17 are still in the old orbits.

In this case, the GPS tuner 2 of the mobile unit 17
6, the moving position is measured based on the satellite signal of the old orbit received by the GPS antenna 25, but the RTCM differential correction value received, demodulated, and converted via the FM multiplex receiver 19 is the new orbit. Since the correction value is changed to the correction value based on the satellite signal, correct correction processing of the mobile body measurement position in the GPS tuner 26 cannot be performed.

Therefore, the DARC → RTCM converter 2 is used.
In No. 4, when the satellite orbit (IODE) obtained from the DARC format changes, the differential correction value according to the RTCM type 1 format is added to the delta value according to the RTCM type 2 format as follows.
GPS tuner 2 with additional differential correction value
6 is given.

That is, the RTCM type 2 format is a differential correction value corresponding to the old orbit (old IODE) of the receiving satellite and a new orbit (new IOD).
E) is calculated by calculating the difference from the differential correction value, that is, in FIG. 9, the new orbit at the time (4) when the orbit information (IODE) obtained from the DARC format changes to the new orbit. Corresponding RTCM
Type 1 differential correction value PRC4 (101),
Along with RRC4 (101), the RTCM2 type delta differential correction value ΔPRC4 (= PRC3 (100) −
PRC4 (101)), ΔRRC4 (= RRC3 (100) -RRC
4 (101)) is added and given to the GPS tuner 26.

As a result, in the GPS tuner 26, even before the orbit of the receiving satellite is updated, the RTC
A differential correction value corresponding to the old trajectory can be obtained based on the differential correction value of the M1 type format and the delta differential correction value of the type 2 format, and correct correction processing of the moving body measurement position can be performed.

[0033]

However, the above-mentioned F
In the DARC → RTCM converter 24 of the M multiplex receiver 19, the RTCM1 type differential correction value corresponding to the new orbit correction value corresponding to the update of the orbit information (IODE) obtained as the DARC format and the correction value between the old and new orbits. Even in the differential GPS in which the RTCM2 type delta differential correction value corresponding to the difference between the two is applied to the GPS tuner 26, for example, immediately after the orbit of the receiving satellite in the fixed reference station 11 is updated, D / GP mounted on 17
When the S receiver 18 and the FM multiplex receiver 19 are activated, the correction value of the DARC format received and demodulated by the DARC → RTCM converter 24 of the FM multiplex receiver 19 is already given to the correction value (PRC) corresponding to the new orbit. (new
IODE), RRC (new IODE)) and the correction value (P
Since RC (old IODE) and RRC (old IODE)) are in the alternate switching state, it is determined whether the correction value is old or new only from the change in the orbit information (IODE) (for example, "100" and "101"). However, there is a problem that the differential correction value cannot be converted into the RTCM format.

This means that, for example, when the moving body 17 passes through a place where FM reception is impossible and moves again to a place where FM reception is possible, the correction value obtained by the DARC format is already switched alternately after the trajectory update. The same applies when in the state.

That is, the conventional differential GP
At S, the orbit information in the DARC format (IO
FM in the moving body 17 during the update process of (DE)
When the reception is activated or becomes receivable, it is not possible to determine the old or new of the above-mentioned orbit information (IODE), and therefore RT
There is a problem that the differential correction value in the CM format cannot be generated and the differential correction processing of the moving measurement position cannot be performed.

The present invention has been made in view of the above problems, and for example, DAR transmitted as FM multiplex broadcasting.
Even if the FM reception is activated on the mobile side or the FM reception becomes possible while the C system D / GPS correction value data is in the process of updating the satellite orbit, the RTCM is immediately released.
It is an object of the present invention to provide a positioning method capable of generating a differential correction value of a method and performing a correct differential correction process.

[0037]

That is, in the positioning system according to the present invention, the positioning information measured based on the signals received from a plurality of satellites is extracted from the multiplexed data multiplexed into the FM signal. Correction is performed based on correction data. Orbit extraction means for extracting orbit information of the receiving satellite from the received satellite signal and satellite orbit information extracted by the orbit extraction means are used for the multiplexing. It is provided with a conversion unit that converts the correction data extracted from the data into RTCM1 type correction data, and a positioning correction unit that corrects the positioning information according to the RTCM1 type correction data converted by the conversion unit. And

[0038]

That is, in the positioning system according to the present invention, the orbit information of the receiving satellite is extracted from the satellite signal received by the GPS receiver, and the DARC data is obtained in correspondence with the orbit information of the GPS receiving satellite. GPS extracted from
Correction data is converted to RTCM1 type correction data, and the positioning information measured by the GPS receiver is corrected according to the converted RTCM1 type correction data. Therefore, even when FM reception is started, Immediately, the RTCM differential correction value corresponding to the receiving satellite orbit in the GPS receiver is generated and corrected.

[0039]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of electronic circuits of an FM multiplex receiver and a D / GPS receiver mounted on a mobile body in a differential GPS implementing the positioning system of the present invention.

The FM multiplex DARC system broadcast signal transmitted from the transmitting antenna 16 (see FIG. 4) is received by the FM tuner 32 of the FM multiplex receiver via the FM antenna 31 attached to the mobile unit, and FM multiplex. Decoder 33
Is supplied to.

This FM multiplex decoder 33 is an FM multiplex DARC that is received and supplied by the FM tuner 32.
The system broadcast signal is demodulated and separated into the FM voice (music) signal and the data of the DARC system format.
The DARC format data demodulated and separated by the M multiplex decoder 33 is output to the differential data extraction unit 35 of the DARC → RTCM converter 34.

This differential data extraction unit 35
Is the D. GPS assigned to two data packets from the DARC format data (see FIG. 5) demodulated and separated by the FM multiplex decoder 33 and output.
Data (see FIG. 6) for extraction, and the D / GP extracted by the differential data extraction unit 35.
The S data includes the PRC extraction unit 36, the RRC extraction unit 37,
It is output to the IODE extraction unit 38.

The PRC extractor 36 receives a fixed reference station (see FIG. 4) from the D / GPS data extracted by the differential data extractor 35.
For example, the pseudo-range correction value PRC corresponding to each of the eight GPS satellites is extracted.
Pseudorange correction value PRC for each satellite extracted by
Is output to the differential correction value calculation unit 39.

The RRC extraction unit 37 receives the D / GPS data extracted by the differential data extraction unit 35 at a fixed reference station (see FIG. 4).
The RRC extraction unit 37 extracts the distance change rate correction value RRC corresponding to each of the eight GPS satellites.
Distance change rate correction value RRC of each satellite extracted by
Is output to the differential correction value calculation unit 39.

The IODE extraction unit 38 corresponds to each of the eight GPS satellites received by the fixed reference station (see FIG. 4) from the D / GPS data extracted by the differential data extraction unit 35. The orbit data IODE is extracted, and this IODE extraction unit 3
Orbital data IODE of each satellite extracted by 8
Is output to the differential correction value calculation unit 39.

Further, the signals from the eight GPS satellites, which are received by the GPS sensor 44 of the D / GPS receiver 43 via the GPS antenna 42 attached to the moving body, are supplied to the positioning CPU 45.

The positioning CPU 45 calculates the pseudo distance to each individual satellite based on the received signal from each satellite, and the calculated pseudo distance to each individual satellite is given by the differential data CPU 46. Correction value PRC and distance change rate correction value RRC corresponding to the satellites of, and the moving position (latitude, longitude, altitude) of the moving body on the earth based on the corrected pseudo distances with the respective satellites. ) Is measured, and the moving position of the moving body measured by the positioning CPU 45 is output to and displayed on the monitor 47.

Further, in the positioning CPU 45, the orbital data IODE of each satellite indicated in the position measuring satellite signal received and supplied from the GPS sensor 44 is the FM.
It is output to the GPS / IODE extraction unit 40 provided in the DARC → RTCM converter 34 of the multiplex receiver, extracted, and output to the differential correction value calculation unit 39.

The differential correction value calculation unit 39
With respect to the orbit data IODE of the position-measuring receiving satellite extracted from the GPS receiver 43 by the GPS / IODE extracting unit 40, the DA data is extracted by the IODE extracting unit 38.
The satellite orbit data IODE extracted from the RC format D / GPS data is judged to be the same, and the same orbit data I as the position measurement receiving satellite orbit data IODE is determined.
Computation and generation of differential correction values PRC and RRC in the RTCM1 format based on the pseudo distance correction value PRC and the distance change rate correction value RRC extracted and output from the PRC extraction unit 36 and the RRC extraction unit 37 corresponding to ODE. Then, this differential correction value calculation unit 3
The differential correction values PRC and RRC in the RTCM1 type format corresponding to the reception satellite orbit data IODE in the D / GPS receiver 43 calculated and generated in 9 are:
The data is formatted via the data formatter 41 and output to the differential data CPU 46 of the D / GPS receiver 43.

That is, as the satellite orbit received by the fixed reference station 11 (see FIG. 4) is updated, the pseudo distance correction value PRC and the distance change rate in the DARC format which are received, demodulated and separated by the FM multiplex receiver. The correction values RRC are the correction values PRC (old IODE) and RR corresponding to the old trajectory, respectively.
C (old IODE) and the correction value PRC (newIODE) corresponding to the new orbit
DE), RRC (new IODE), when the satellite orbit of the GPS satellite for position measurement received by the D / GPS receiver 43 remains in the old orbit in a state of being alternately switched and given, In the GPS / IODE extraction unit 40, D.
Old orbit data from the positioning CPU 45 of the GPS receiver 43
Since (old IODE) is extracted, in the differential correction value calculation unit 39, the IODE extraction unit 38 causes the DARC
The DRC format correction values PRC (old IODE) and RRC (old IODE) at the time when the old orbit data (old IODE) of the D / GPS data in the format are extracted are PRC.
The RTC is extracted from the extraction unit 36 and the RRC extraction unit 37.
It is generated as a differential correction value in the M1 format.

In the same manner as described above, the fixed reference station 11 (see FIG.
(Refer to), the pseudo-range correction value PRC and the distance change rate correction value RR in the DARC format that are received, demodulated and separated by the FM multiplex receiver with the update of the satellite orbit.
C is the correction value PRC (old IOD
E), RRC (old IODE) and correction value PR corresponding to the new orbit
When the satellite orbits of the position measurement GPS satellites received by the D / GPS receiver 43 are in new orbits while being alternately switched between C (new IODE) and RRC (new IODE). In the GPS / IODE extracting section 40, the new orbit data (new IODE) is extracted from the positioning CPU 45 of the D / GPS receiver 43. Therefore, in the differential correction value calculating section 39, the IODE extracting section 38 in the DARC format is used. DARC format correction values PRC (new IODE) and RRC (new IODE) at the time when new orbit data (new IODE) of D / GPS data was extracted
Are extracted from the PRC extraction unit 36 and the RRC extraction unit 37, and are generated as differential correction values in the RTCM1 format.

That is, even when the satellite orbit of the receiving satellite in the fixed reference station 11 is updated and the orbit of the D / GPS data given in the DARC format is being updated, the differential correction value calculation unit 39 outputs D
-Corresponding to the current satellite orbit of the position measurement receiving satellite in the GPS receiver 43, the correction value of either the new or old orbit being updated in the DARC format is selected,
Since it is generated as a differential correction value in the RTCM1 type format, the differential data CPU 46 of the D / GPS receiver 43 has a positioning CPU 45.
The differential correction value of the RTCM1 type format, which always coincides with the satellite orbit of the receiving satellite used for the position measurement processing in step 1, is given.

As a result, the D / GPS receiver 43
In the positioning CPU 45, the pseudo distance with each satellite, which is calculated based on the received signal from each satellite, is always accurately and differentially corrected, and the fixed reference station 11 and D / GPS receiver 43 Timing deviation of receiving satellite orbit update and FM in mobile
Highly accurate moving position measurement processing is performed regardless of the reception start timing and the like.

FIG. 2 shows the DARC of the FM multiplex receiver mounted on the mobile body in the differential GPS.
7 is a flowchart showing a differential correction value generation process in the RTCM converter 34.

FIG. 3 shows the DARC → RTCM converter 34.
FIG. 7 is a diagram showing differential correction values of the RTCM1 type format generated in accordance with the differential correction value generation processing of FIG.

That is, the DARC → RTCM converter 34
In the differential correction value calculation unit 39 of
-GPS I from the positioning CPU 45 of the GPS receiver 43
The orbit data IODE of the receiving satellite in the GPS receiver 43 is read via the ODE extracting section 40 (step S1).

Further, from the FM multiplex decoder 33 to the differential data extraction unit 35 and the PRC extraction unit 36, R.
Via the RC extraction unit 37 and the IODE extraction unit 38, the pseudo distance correction value PRC, the distance change rate correction value RRC, and the satellite orbit data IODE in the DARC data received as FM multiplex broadcasting are taken in (step S2). .

Then, the satellite orbit data IODE (DARC) in the DARC data fetched in step S2.
And it is determined whether or not the received satellite orbit data IODE (GPS tuner) in the GPS receiver 43 read in step S1 matches (step S3).

Here, for example, the pseudo distance correction value PRC and the distance change rate correction value RR in the DARC data are accompanied with the update of the satellite orbit received by the fixed reference station 11 (see FIG. 4).
C is the correction value PRC (10
0), RRC (100) and the correction value P corresponding to the new orbit
In the state in which RC (101) and RRC (101) are alternately switched over and taken in, the receiving satellite orbit in the GPS receiver 43 remains the old orbit "100", and the DAR
Correction value PRC (10
0) and RRC (100) are taken in, the IOD
When it is determined that E (DARC) and the IODE (GPS tuner) match, the DARC format correction values PRC (100), R corresponding to the old orbit data "100".
RC (100) is directly converted to the differential correction value of the RTCM1 type format, and as shown in FIG. 3, PRC1 (100), RRC1 (100)
As a result, it is given to the differential data CPU 46 of the GPS receiver 34 (step S3 → S).
4).

Thereafter, in the same manner as described above, the DAR is updated as the satellite orbit received by the fixed reference station 11 (see FIG. 4) is updated.
The pseudo distance correction value PRC and the distance change rate correction value RRC in the C data respectively correspond to the correction value PRC (1
00), RRC (100) and the correction values PRC (101), RRC (101) corresponding to the new orbit, the receiving satellite orbit at the GPS receiver 43 is switched to the old orbit in a state of being alternately switched. With 100 ”, the DA
Correction value PRC (10 corresponding to the new orbit in RC data
1), when the RRC (101) is taken in, the IOD
If it is determined that E (DARC) and IODE (GPS tuner) do not match, the correction value PR corresponding to the old orbital data “100” acquired as the previous DARC data.
A differential correction value in the RTCM1 type format is generated from C (100), RRC (100). For example, as shown in FIG. 3, PRC2 (100), RRC2
As (100), it is given to the differential data CPU 46 of the GPS receiver 34 (steps S3 → S5, S4).

Further, in the same manner as described above, with the update of the satellite orbit received by the fixed reference station 11 (see FIG. 4), the DAR
The pseudo distance correction value PRC and the distance change rate correction value RRC in the C data respectively correspond to the correction value PRC (1
00), RRC (100) and the correction values PRC (101), RRC (101) corresponding to the new orbit, the satellite orbit received by the GPS receiver 43 is changed to the new orbit in a state of being captured alternately. 101 ", and the DAR
Correction value PRC (10
1), when the RRC (101) is taken in, the IOD
If it is determined that E (DARC) and the IODE (GPS tuner) match, the DARC format correction values PRC (101), R corresponding to the new orbit data "101".
RC (101) is directly converted to the differential correction value of the RTCM1 type format, and as shown in FIG. 3, for example, PRC4 (101), RRC4 (101)
As a result, it is given to the differential data CPU 46 of the GPS receiver 34 (step S3 → S).
4).

Therefore, according to the differential GPS having the above-described configuration, the orbit data IODE (GPS tuner) of the receiving satellite in the D / GPS receiver 43 is provided in the DARC → RTCM converter 34 of the FM receiver.
The PS / IODE extraction unit 40 extracts and supplies it to the differential correction value calculation unit 39.
Then, DARC that is multiplexed with FM broadcast and received and demodulated
From the D / GPS data in the data, the GPS / IO
D / GPS receiver 4 extracted by the DE extraction unit 40
Pseudo range correction value PRC and range change rate correction value RRC corresponding to satellite orbit data IODE (GPS tuner) in 3
Then, the differential correction value of the RTCM1 type format is generated and given to the differential data CPU 46 of the D / GPS receiver 43, and the positioning CPU 45
Since the differential correction of the measurement position at is performed, even when the D / GPS receiver and the FM multiplex receiver are activated or the FM reception is moved to a possible place while updating the orbit data in the DARC format. , RT-CM of orbital data that matches the satellite orbital data received by the D / GPS receiver 43
The differential correction value of the type 1 format is immediately given, and the correct differential correction processing can always be performed.

Then, the differential G having the above structure
In PS, only the differential correction value of RTCM1 format is generated and D.
Since it is sufficient to send it to the GPS receiver 43, in such a case, it is added to the differential correction value of the RTCM1 type format to generate the delta differential correction value of the RTCM2 type format, and compared with the conventional differential GPS which is sent to the GPS tuner. And then F
RTC from M multiplex receiver to D / GPS receiver
Generation of M data and communication time can be significantly shortened, and in particular, position measurement accuracy during satellite orbit update can be improved.

[0065]

As described above, according to the present invention, for example, G
A differential GPS that corrects positioning information measured based on signals received from a plurality of satellites in a PS receiver based on GPS correction data extracted from DRAC data multiplexed into an FM signal, Orbit information of the receiving satellite is extracted from the satellite signal received by the GPS receiver, and the GPS correction data extracted from the DARC data is RTCM1 type correction corresponding to the orbit information of the GPS receiving satellite. Converted to data,
Since the positioning information measured by the GPS receiver is corrected according to the converted RTCM1 type correction data, even when the FM reception is started, the RTCM system corresponding to the receiving satellite orbit in the GPS receiver is immediately used. The differential correction value is generated and the correction process is started.

Therefore, for example, when the DARC correction value data of the DARC system transmitted as FM multiplex broadcasting is in the process of updating the satellite orbit and the FM reception is activated on the mobile side, or the FM reception becomes possible. Even if it happens, immediately generate the RTCM differential correction value,
It becomes possible to perform correct differential correction processing.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of electronic circuits of an FM multiplex receiver and a D / GPS receiver mounted on a mobile body in a differential GPS according to an embodiment of a positioning system of the present invention.

FIG. 2 is a flowchart showing a differential correction value generation process in a DARC → RTCM converter of an FM multiplex receiver mounted on a mobile body in the differential GPS.

FIG. 3 is an RTC generated along with a differential correction value generation process in the DARC → RTCM converter.
The figure which shows the differential correction value of M1 type format.

FIG. 4 Differential G using FM multiplex broadcasting
The figure which shows the whole structure of PS.

FIG. 5 is a diagram showing a configuration of a DARC transmission frame multiplexed in FM broadcasting.

FIG. 6 is a diagram showing the contents of data for D / GPS assigned to two packets of the DARC transmission frame.

FIG. 7 is a diagram showing the contents of a correction data set of each satellite given as the D / GPS data.

FIG. 8: D / G mounted on a conventional D / GPS mobile unit
The block diagram which shows the structure of PS receiver and FM multiplex receiver.

FIG. 9: F mounted on the conventional D / GPS mobile unit
The figure which shows the conversion state of the correction value data (PRC, RRC) by the DARC-> RTCM converter of an M multiplex receiver.

[Explanation of Codes] 11 ... D GPS fixed reference station, 12a, 12b, ... GP
S satellite, 13 ... FM multiplex DARC data control unit, 14 ...
Modulator, 15 ... transmitter of FM station, 16 ... transmitting antenna,
17 ... Moving object, 31 ... FM antenna, 32 ... FM tuner, 33 ... FM multiplex decoder, 34 ... DARC → RTC
M converter, 35 ... Differential data extraction unit, 3
6 ... PRC extractor, 37 ... RRC extractor, 38 ... IOD
E extraction unit, 39 ... Differential correction value calculation unit, 4
0 ... GPS / IODE extraction unit, 41 ... Data formatter, 42 ... GPS antenna, 43 ... GPS receiver, 4
4 ... GPS sensor, 45 ... Positioning CPU, 46 ... Differential data CPU, 47 ... Monitor.

Claims (1)

[Claims] 1. A positioning method, wherein positioning information measured based on signals received from a plurality of satellites is corrected based on correction data extracted from multiplexed data multiplexed on an FM signal. Orbit extraction means for extracting orbit information of the receiving satellite from the satellite signal, and correction data extracted from the multiplex data corresponding to the satellite orbit information extracted by the orbit extraction means, R
A positioning method, comprising: a conversion unit that converts into TCM1 type correction data; and a positioning correction unit that corrects the positioning information according to the RTCM1 type correction data converted by the conversion unit.