JPH02247591A - position measurement system - Google Patents

Abstract

PURPOSE:To narrow the band of a signal and to take a measurement with high accuracy by measuring the position of a mobile station with the phase delay quantity of a master station and the phase delay quantities of slave stations which are sent from 1st and 2nd slave stations. CONSTITUTION:The master station 4 and 1st and 2nd slave stations 2 and 3 receive sent signals to measure the phase delay quantities and the phase delay quantities which are measured by the slave stations 2 and 3 are sent to the master station 4. The master station 4 calculates the positions of the slave stations 2 and 3 from the phase delay quantity that the master station itself calculates and the phase delay quantities sent from the slave stations 2 and 3 and the slave station positions are displayed with position data which are the calculation results. A track Ia is calculated from the phase difference between the master station 4 and slave station 2, a track Ib is calculated from the phase difference between the master station 4 and slave station 3, and the intersection of the tracks Ia and Ib is determines as the position of the mobile station 1. Thus, the mobile station 1 sends a sine wave measurement signal, so the band of the signal may be narrow. Further, the slave stations 2 and 3 and master station 4 multiply their received signals respectively to improve the measurement accuracy, so the measurement accuracy of the mobile station 1 can be improved.

Description

[Detailed Description of the Invention] (Requires 11) Regarding a position measurement system for measuring the position of a mobile station, the purpose is to narrow the signal band and have a high degree of W!W!, and to measure the burst shape of a sine wave. A mobile station transmits a signal, and a measurement signal from the mobile station is received and multiplied to a plurality of different frequencies, and each of the obtained plurality of multiplied signals is divided into !!i quasi(1 and A plurality of slave stations that compare and measure the amount of phase delay of the slave stations, and a plurality of slave stations that receive measurement signals from the mobile station and multiply them to a plurality of different frequencies, each of which has the same frequency. a parent station that measures the phase delay amount of the master station in comparison with a reference signal of the parent station, and measures the position of the mobile station based on the phase delay amount of the master station and the phase delay amount of the slave stations transmitted from the plurality of slave stations. Contains and configures.

[Industrial application field]

The present invention relates to a location system for determining the location of a mobile station.

Conventionally, N1 is used to measure the position of mobile stations such as self-am, people, etc.
There is a fixed system. Such a system is required to be small in scale and to have high positional accuracy.

[Conventional technology]

Conventional position measurement systems include: 0) GPS (global positioning) for moving objects;
A method of measuring the position using the position information signals of at least three GPSlfi stars by providing a GPS receiver that receives position information signals from Si using A method of receiving pulse signals from two fixed stations using direction finders and measuring the position at the intersection of the directions of the moving object from these two fixed stations. There is a method of measuring the position by hyperbolic navigation, which receives the signals from each station and determines the distance to each station by the phase difference between each station's pulse signal @ darkness.

(Problems to be Solved by the Invention) The conventional method requires a plurality of satellites, resulting in a large scale of the entire system and a problem in that the cost is extremely high.

Method (1) is based on the fact that the position accuracy deteriorates as the distance between the moving object and the fixed station increases due to the accuracy of the direction finder11.
There are 9 INs.

Method (2) has a problem in that in order to increase the degree of position, the edge of the pulse must be steep, and the position accuracy is limited by the bandwidth of the transmitted pulse.

The present invention has been made in view of the above points, and an object of the present invention is to provide a position measuring system in which the signal band can be narrowed and the position 1fJtff is high.

(Means for solving problems) FIG. 1 shows the original coral diagram of the system of the present invention.

In the figure, the moving jS1 transmits a sinusoidal burst measurement signal.

w41. Each of the second slave stations 2 and 3 receives the measurement signal from the mobile station 1, transmits it to a plurality of different frequencies, and compares each of the obtained multiplied signals with a reference signal having the same frequency. and measure the amount of phase delay of the slave station.

The master station 4 receives the measurement signal from the mobile station 1, multiplies it to a plurality of mutually different frequencies, compares each of the obtained multiplied signals with a reference signal having the same frequency, and calculates the phase of the master station. The amount of delay is measured, and the amount of phase delay of the master station and the first. The position of the mobile station 1 is measured based on the phase delay amount of the slave station transmitted from the second slave station 2.3.

(Function) In the present invention, since the mobile station 2 transmits a sine wave measurement signal, the band of the transmission signal can be narrow.

In addition, each of the 1st and 2nd slave stations 2.3 and t1 station 4 sequentially measures the phase MK amount using a multiplied signal obtained by multiplying the received measurement signal to a plurality of frequencies.
2. The positional accuracy of item 2 is improved.

(Embodiment) Figure 2 shows a block diagram of a mobile station. In the figure, oscillation!
A highly stable reference signal having a frequency of -IMHz outputted from the substation 120 is supplied to the branching unit 21 and the AM transformer A 22.

The splitter splits the reference signal to obtain a split signal (sine wave) of, for example, 10 KHz, and supplies it to the control section 23 . &1111
The aB23 extracts the above-mentioned frequency-divided signal in a burst form from the terminal 27 in response to the measurement start signal from the master station, and performs amplitude modulation (AMI
control) unit 22.

The AM modulator 22 performs AM modulation on the reference signal using a burst-like frequency-divided signal, that is, a measurement signal to obtain a high frequency signal in the UHF or VHF band. This high frequency signal has unnecessary frequency components removed by a bandpass filter 24, is amplified by an amplifier 25, and is transmitted from an antenna 26.

FIG. 3 shows a block diagram of the slave station. In the figure, antenna 3
A high frequency signal output from a mobile station is received at 0, band limited by a bandpass filter 31, and amplified by an amplifier 32.
The signal is supplied to the M demodulator 33.

The AIVLtl:l device 33 demodulates the measurement signal from the received high frequency signal. This demodulated signal (burst sine wave) is supplied to each of the multipliers 34, 35, and 36, and the multiplier 34 is
The frequency is multiplied by i to, for example, 30 KHz, and the multiplier 35 is multiplied by m2 to set the frequency to, for example, 300 KHz.
6 is third multiplied to, for example, a frequency of 3 MHz, and the respective multiplied signals are supplied to phase delay measuring devices 37, 38, and 39.

The stable reference signal (sine wave) with a frequency of several tens of MHz output from the oscillator 41 is measured by a phase delay measuring device 37, 38, and 39, respectively.
supplied to The oscillator 41 connects the terminal 42 with l1l from the m station.
Synchronization 1I1 is performed by the synchronization control unit 43 supplied with the tl signal.
1111 is performed and synchronized with the reference signal at the master station, and the measurement start 8I bar is set based on the measurement n start signal from the master station.

Each of the phase delay measuring devices 37, 38, and 39 measures the phase delay l of each multiplied signal and outputs the measured signal from the interface 44 to the terminal 45.
It is transmitted to the master station via.

FIG. 4 shows a 70 block diagram of the master station. In the figure, antenna 5
A high frequency signal output from the mobile station 0 is received, band limited by a bandpass filter 51, amplified by an amplifier 52, and supplied to an AM repeater 53. .

The AMv111 device 53 receives the measurement signal from the received high frequency signal.
II. This demodulated signal (burst sine wave) is supplied to each of the multipliers 53, 54, and 55, and the multiplier 53
The multiplier 54 multiplies the frequency to, for example, 30 KHz, and the multiplier 54 multiplies the frequency to, for example, 300 KHz.
is third-multiplied to, for example, a frequency of 3 MHz, and the respective multiplied signals are supplied to phase delay measuring devices 57, 58, and 59.

Highly stable reference signals with a frequency of 1 MH2 outputted from the oscillation 161 are supplied to phase delay measuring devices 57.58.59, respectively. The oscillator 61 is synchronized by a synchronization section 63. Further, the synchronization unit 611111 63 supplies a synchronization signal and a measurement start signal to the slave station from the terminal 62, and supplies a measurement start signal to the mobile station.

Each of the phase delay measuring devices 57, 58, and 59 measures the phase delay l of each multiplied signal and calculates the position l! 164. At this point, a phase delay device is supplied to the ffi calculation unit 64 from the slave station via a terminal 65, and the position data of the mobile station calculated by the position calculation unit 64 is displayed on the display 66.

FIG. 5 shows a flowchart of the position determination process of the system of the present invention.

In the figure, in step 71, the master station sends a message a to the mobile station and slave station.
The start of m-setting is instructed. As a result, the mobile station and the slave station perform the measuring device 6 (step 72), and the mobile station starts transmitting (step 73).

The master station and the slave station receive the transmitted signal and measure the phase delay (step 74), and the phase delay measured by the slave station is transmitted to the master station (step 75). The master station calculates the position of the slave station from the amount of phase delay it has measured and the phase delay black transmitted from the slave station (step 76). The slave station position is displayed using the position data that is the calculation result (
Step 77).

If the angular frequencies of the measurement signals of the mobile stations are ω, then the master station and the first . The demodulated signals of each of the second slave stations are as shown in 1.

l1 station Sin ((c)1 t+n+ X+θ1+δ
) First slave station 5iJ1 ((lc>+ j-1nz
π ten θ2] δ) second subordinate 74 Sin (ωIj+n
37E+θ3+δ) Here, n views π→・θ1. n2π”-
θ2°n3π+03 is the phase difference caused by the distance from the mobile station to each station, and δ is the phase difference up to the AMI tuning of the receiver, which is assumed to be the same for each js.

When the demodulated signal is multiplied by ml, 2nd, and 3rd, respectively, it is expressed as follows.

@74 Sin (m+ Q)It+m+ (n
+ π + θ + δ)) Sin (mz ωI t-1-mz (n+ 7t
+θ1 +δ) ) Sin (ms (t)+ t-tml (n+
π+θ1+δ)) First slave fj4 Sin (ml (J)+j(m
I (nz 1C+θ2+δ)) Sin (mz (t)I t-1m2 (nz
π+θ2 +δ) ) Sin (mz (t)r j+m!(nz 7C
+02 +δ)) Second minor 8 sin (m+ U)+ t-Im+
(n3π+θ3 +δ) ) Sin (mz (t)+t(ml (nz 7
t+θ3 +δ) ) Sin (ms (t)Ij(・mz (n3
π+θ3+δ〉) For convenience, FIG. 6(A) shows a multiplied signal obtained by multiplying the tllil signals of the master station, the first slave station, and the second slave station by m1 times.

Expressed as a square wave as shown in (D) and (E), mz/m+ =
2. Assuming ms/mz-2, mlM times that of the master station,
The multiplied signal multiplied by ml is shown in the same figure (B).

The signal of the first slave station multiplied by mz and ms becomes as shown in (E) and (F) of the same figure, and the signal of the second slave station multiplied by ml1Ii and multiplied by ms becomes ( H), (1)
The result will be as shown below.

The phase delay in simultaneous opening of each of the above waveforms is determined.

Now, the phase difference between the reference signals of each station is set to γ1. When γ2°γ3, the phase delay amount is expressed as follows.

Ij8 m+ (n+ 7E101+δ)-71
m2 (n, π+θ1+δ)-7+ ml (n, π+θ1+δ)-γ1 Slave station 1m+(n2π→・θ2→~6)-γ2m, (n2
π+θ2+6)-12 ms (n2π+θ2+6)-γ2 Slave station 2 ml (ng M+03+δ)-13m2
(n3π+θ34δ)−γ3 ms (nsπ103+δ)−18 Assuming that the phase difference S between the four rotations and the first slave station and the fixed time tas are the same, the frequency of mxω is as follows.

(nl -nz) 7rml + (01-02)J
+(γ1-γ2) If the frequency to be multiplied is selected so that the wavelength of the signal multiplied by m is greater than the distance to be measured, the following equation holds true.

(n+ -nz >7rm+ =O If the phase difference between the ^ stable reference signals of I18 and the first slave 8Iil is known or the 8-cycle period for each is set, γ1°T2 becomes a known quantity, and (θ1-θz) /m+ can be obtained.In order to obtain the accuracy of θ1 and θ2, the multiplication frequency is increased and the measurement is performed.

If the measurement accuracy of the phase difference is π15 (36 degrees), the accuracy at a distance of 1000 m can be obtained at a frequency of 30 KHz, and at a frequency of 3
At 00 KHz, an accuracy of distance 100711 is obtained, and at a frequency of 3 MHz, an accuracy of distance 11110 m is obtained.

Therefore, the position calculation unit 64 measures the approximate phase difference at the frequency of mtω-, and sequentially measures the phase difference at the frequency of m2ω1 and m3ω1 to improve measurement accuracy.

In this way, the phase difference between the master station and the first slave station (phase difference ψ1 shown in Fig. 6) is determined, and the trajectory ■
a is calculated.

In the same way, the phase difference between the master station and the second slave station (phase difference ψ2 shown in FIG. 6) is determined, and the trajectory Ib shown by the dashed line in FIG. 1 is excluded. The intersection point is determined to be the location of the mobile station.

In this way, since the mobile station transmits a sinusoidal measurement signal, the band of the transmission signal can be narrow.

Also, 1st. Each of the second slave station and the master station sequentially measures the amount of phase delay using a multiplied signal obtained by multiplying the received measurement signal to a plurality of frequencies to improve measurement accuracy, thereby improving the positioning accuracy of the mobile station.

Also,! The system can be configured on a relatively small scale, consisting of a g station, a mobile station, and at least two slave stations, and the cost does not increase.

Note that instead of the high frequency signal obtained by AM modulation from the mobile station, the carrier signal itself is sent in a burst as a measurement signal (HL), and this may be received by the slave station and the master station, and is not limited to the above embodiment. .

〔Effect of the invention〕

As described above, according to the position measuring system of the present invention, the band of the signal to be transmitted can be narrow, the position accuracy can be increased, and the system scale can be small, making it extremely useful in practice.

[Brief explanation of drawings]

Fig. 1 is an original diagram of the present invention, Fig. 2 is a block diagram of a mobile station, Fig. 3 is a block diagram of a slave station, Fig. 4 is a 10-step diagram of a master station, and Fig. 5 is a position of the system of the present invention. Flowchart of the measurement system. Figure 6 is a timing chart of the multiplied signals of each station. 20.41.61 is an oscillator, 23 is an AM modulator, 33.53 is an AM receiver II, 34.~36.54~56 is a multiplier, 37~39.57~59 is a phase delay measuring device, 44 is a An interface section, 64 indicates an output section. Patent applicant: Fujitsu Co., Ltd. Agent: Tadahiko Ito In Figure 8, 1 is a mobile station, and 2.3 is a slave station. 4 is the master station, Figure 1 is the station numbered 7'o-/2, Figure 2 is the next station's b-72, Figure 3 is the south cup of the cup, 10-y2Yj8, Figure 4, Figure 5.

Claims (1)

[Claims] A mobile station (1 mobile station) that transmits a sinusoidal burst measurement signal.
), the measurement signal from the mobile station (1) is received and multiplied to a plurality of different frequencies, and each of the obtained multiplied signals is compared with a reference signal having the same frequency to determine the phase of the slave station. A plurality of slave stations (2, 3) that measure the amount of delay and a measurement signal from the mobile station (1) are received and multiplied to a plurality of mutually different frequencies, and each of the obtained plurality of multiplied signals is multiplied by a frequency. The phase delay amount of the master station is measured by comparing it with the same reference signal as the reference signal, and the phase delay amount of the master station and the plurality of slave stations (2
, 3) and a master station (4) that measures the position of the mobile station (1) based on the amount of phase delay of the slave station transmitted from the master station (4).