JPH09138269A - Position confirmation system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a position confirmation system in which an operation at an apparatus on the side of a station to be searched is not required at all, in which high-accuracy information about a search can be obtained on the side of a searching station, in which an erroneous transmission on the side of the station to be searched is prevented, in which the consumption of a battery is reduced to a minimum and by which the position of the station to be searched can be confirmed. SOLUTION: A position confirmation system is provided with a station 1, to be searched, which is carried by a side to be searched such as a victim or the like and with a searching station with which a moving body such as an airplane or the like is equipped. When the station to be searched is designated individually from the searching station, it holds a holding circuit, it starts a transmission in such a way that a positioning signal sent automatically from the searching station is superposed on response radio waves, and it returns the signal to the searching station. In the searching station, the positioning signal from the searching station is compared with the positioning signal returned from the station to be searched, the delay time which is required for a forward and backward operation is measured, and a distance between the searching station and the station to be searched is found. This measuring operation is performed in three or more different positions, and the position of the station to be searched is decided on the basis of measured results.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a position confirmation system for confirming the position of a searched station. For example, it is possible to confirm the position of a victim in sea distress, mountain distress, etc., position confirmation of cargo, etc. It can be used for position confirmation, confirmation of fishing net position on the sea, and other purposes.

[0002]

2. Description of the Related Art There are the following conventional techniques. Example-1 Method using radar transponder Example-2 Method using direction finding Example-3 Method using satellite Example-4 Method combining pager and GPS

Example-1 Method Using Radar Transponder When a radar signal from a search station is detected, a device (radar transponder) that emits a response radio wave that produces bright spots arranged at regular intervals on the display of the radar device on the search station side is installed. In preparation for the victims' side, when a distress accident occurs, the victims turn on the radar transponder and start operating as a station to be searched, and wait for the search by the radar signal of the search station.
When the searched station receives a radar radio wave from the search station, the searched station emits the response radio wave and a plurality of bright spots are lined up at a constant interval on the display of the radar device of the search station. It can be confirmed by the start position of the bright spot signal. Even if there are many reflections from radar signals, such as in rough seas, this method allows multiple luminances to be lined up on the display of the radar device at regular intervals, so the position of the searched station can be grasped compared to ordinary radar searches. Easy to do.

Example 2 Method by Direction Detection A device for transmitting a radio wave signal for searching for a victim of a predetermined frequency and a predetermined format is provided on the searched side of the victim to prepare for the accident. The side turns on the device, continuously emits a radio signal for searching for the victim, and waits for the search by the search station. The search station confirms the direction of arrival of this radio signal with a direction finder mounted on a ship, aircraft, etc. to grasp the direction in which the searched station is located, and visually finds a victim while moving along the direction line. Try to do so. Since the search can be performed while being guided by the radio signal for searching the victims, the search can be performed more efficiently than the search only by visual inspection.

Example 3 Method Using Satellite A device for transmitting a radio wave signal for searching a victim of a predetermined type at a predetermined frequency for searching for a victim is provided on the searched station side of the victim to provide a disaster accident. When the occurrence occurs, the victim side turns on the power of this device, continuously emits a radio signal for searching the victim, and waits for the search by the search station. When a satellite in orbit around the earth comes directly above the victim, the predetermined radio signal is relayed to the satellite and transmitted to the search station. The position of the victim is confirmed by the position in the orbit where the satellite captures the radio signal for searching the victim from the station to be searched.

Example-4 Method combining pager and GPS, etc. This idea was found during prior art search at the time of filing of the present application, and is disclosed in the application publication (JP-A-6-123767).
Since it was described in, I will introduce the summary. On the searched side, a receiving device (pager) for individual selection call and G
It has a PS (Global Positioning System), and when the search station is designated by the pager, the search station measures its own position by GPS and informs the search station. With this, the position of the target searched station is grasped. In addition, in this patent publication, a predetermined radio wave is emitted to a searched station designated by a pager, and this radio wave is captured by a direction finder provided on the side of the searched station to confirm the position of the searched station. The description is briefly described.

[0007]

Since the conventional position confirmation system has been configured as described above, it has the following problems.

Example-1 Method Using Radar Transponder The device mounted on the searched station side receives a radar signal and transmits a radio wave in the radar frequency band (9 GHz) according to the received signal, and has a predetermined travel width. It must be a technical product that can properly transmit ultra high frequency signals that can be swept away. Also, since this device emits a response signal when receiving ordinary radar radio waves, in handling, it should never emit unnecessary radio waves even when receiving radar radio waves in normal times, and people who do not have knowledge in an emergency This equipment must be able to be switched on and operated properly. Therefore, the device itself is complicated, and various complicated operational arrangements and structurally large auxiliary devices are required. In addition, since the power consumption of a radar transponder is relatively large, it is a serious and complicated task to manage the life of the battery so that the battery can operate reliably in an emergency. Therefore, it is a general purpose device for rescue, but it cannot be said to be maintenance-free.

Example 2 Method by Direction Detection In the search by this method, it is a task to confirm only the azimuth of the searched station and then to find the searched station by visual inspection, so the search time tends to be long. However, the search method is inferior to the radar transponder method because the search is difficult at night or in bad weather. Also,
Since the searched station side has a structure that emits radio waves when the power is turned on, it is necessary to prevent unnecessary radio waves from being emitted due to erroneous operation other than in an emergency, and to ensure that people who do not have knowledge in an emergency rarely occur. It must be able to operate. In order to meet this demand, it is necessary to complicate the configuration of equipment and equip a large battery, and it cannot be said that maintenance-free. Also, the operational agreement is complicated.

Example 3 Method of using satellite In this method, the information of the victim cannot be transmitted to the search station until the satellite is almost directly above the station to be searched, so the radio signal continues for a long time. Will need to be sent. Therefore, it is necessary to prepare a device having a large battery on the searched station side. In this type of device, the size of the battery influences the size of the device, and thus there is a problem that miniaturization becomes difficult. In addition to this, as in the method using radar transponders, direction detection, etc., the equipment is complicated for the reliable prevention of unnecessary radio wave emission and the reliable operation in an emergency, and the handling arrangement is complicated. There are problems such as.

Example 4 Method of combining pager and GPS, etc. Since this method requires mounting a considerably large device called GPS, it is essential to construct an ultra-small device such as a card size as the device to be searched. There is a problem that it is not suitable for people. Further, the direction finding method described in this patent publication is similar to the direction finding method shown in the above-mentioned Example 2 since there is no description about the fact that the positioning accuracy of the searched station is specifically devised. It is assumed that things are used. However, according to what is described in this patent publication, the search target station is made up of an ultra-compact one such as a card size, and the measurement accuracy required for efficient search activity is basically secured. There is a problem that the intellectual problem has not been solved.

The present invention has been made in view of the above problems in a search for determining the position of a search target and the like. It is an object of the present invention to provide a position confirmation system which can secure high convenience and reliability in terms of handling, maintenance, etc. and can secure a predetermined accuracy as a system.

[0013]

[Means for Solving the Problems]

Means 1 In order to achieve the above object, the position confirmation system according to the present invention includes a search station carried by a searchee such as a victim and a search station equipped on a moving body such as an aircraft. The station is equipped with an individual identification signal detection circuit, an individual identification signal receiver that receives and detects the individual identification signal sent from the search station, and a positioning signal reception circuit. A positioning signal receiving unit that receives and demodulates a signal, a response transmitting unit that includes a modulator circuit and a transmitting circuit, and that sends the positioning signal obtained by the positioning signal demodulating circuit to a search station, and the individual identification signal. A holding unit provided with a holding circuit that receives the output signal of the detection circuit and continues the holding operation for a preset time, and a holding operation that holds the holding unit The search station is provided with a signal generator for transmitting the individual identification signal and the positioning signal whose durations are set to predetermined values, and a modulation circuit and a transmission circuit for the individual identification signal and the positioning signal. It is equipped with a transmitter that transmits the transmission signal modulated by the signal to the searched station, and a demodulator circuit.The positioning signal sent from the searched station and returned to the searched station via the searched station is received and demodulated. The positioning section obtained by the receiving section is compared with the positioning signal sent from the transmitting section, and the measuring point where the search station is placed based on the comparison result. To the searched station, a self-position calculation location section that confirms the position of the searched station at each measurement point, and a distance from each of the multiple measured points to the searched station. Information and each measurement And a position deciding unit for deciding the position of the searched station based on the self-position information of the searched station, and searching from each of the measurement points obtained by measuring at a plurality of points while the searching station moves. The position of the searched station is determined based on the distance information to each station.

Means 2 In order to achieve the above object, in the position confirmation system according to the present invention, in addition to the first means, the positioning signal receiving section receives the positioning signal sent from the search station and demodulates it. In addition to the positioning signal demodulation circuit, a positioning signal detection circuit that outputs a detection signal while the positioning signal continues is provided, and in addition to the fact that the transmission activation unit is driven by the output signal of the individual identification signal detection circuit and holds for a predetermined time, this When the output signal from the positioning signal detection circuit is received during the holding period, a holding unit that continues holding while the output signal of the positioning signal detection circuit continues is provided, and the positioning signal sent back from the searched station to the searching station Made it possible to extend the duration.

Means 3 In order to achieve the above-mentioned object, the position confirmation system according to the present invention comprises, in addition to the first means, a power supply switch unit that intermittently repeats the on / off state at a fixed cycle, and holds it. While the unit is not in the holding state, the ON / OFF operation of the power switch unit causes the operation of the searched station to be intermittently received at a constant cycle.

Means 4 In order to achieve the above object, the position confirmation system according to the present invention comprises, in addition to the second means, a power supply switch unit that intermittently repeats an on / off state at a fixed cycle, and holds it. While the unit is not in the holding state, the ON / OFF operation of the power switch unit causes the operation of the searched station to be intermittently received at a constant cycle.

Means 5 In order to achieve the above object, the position confirmation system according to the present invention as set forth in claim 5 is such that the length of the off period is sequentially changed in addition to the first or second means. It has a power switch part which repeats ON / OFF state controlled intermittently, and while the holding part is not holding, the OFF period of the searched station is sequentially changed by the ON / OFF operation of this power switch part. The intermittent reception is controlled as described above.

Means 6 In order to achieve the above object, in addition to the means of the first or second aspect, the position confirmation system according to the present invention is such that the length of the off period changes in random order and intermittently turns on / off. A power switch unit that repeats the state is provided, and while the holding unit is not holding, the operation of the searched station is controlled by the ON / OFF operation of this power switch unit so that the OFF period is controlled to change in random order. I decided to do it.

Means 7 In order to achieve the above object, the position confirmation system according to the present invention employs a plurality of measurements at the search station in the first, second, third, fourth, fifth and sixth means. In the search bureau of
Moreover, all the search stations measure the distance to the searched station at at least three measuring points in total, and integrate the measured data to determine the position of the searched station.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. It should be noted that the position confirmation system according to the present invention is assumed to be activated after the object to be searched is specified.

Embodiment 1 FIG. 1 shows the configuration of a searched station 1. FIG. 5 shows the configuration of the search station 2. The searched station 1 shown in FIG. 1 and the searched station 2 shown in FIG. 5 are combined to form a position confirmation system according to the first embodiment of the present invention. In FIG. 1, 11 is a receiving antenna of the station to be searched 1, 12 is an individual identification signal receiving section having an individual identification signal detection circuit 121 for detecting an individual identification signal, and 13 is a positioning signal demodulation circuit 131. A positioning signal receiving unit, 14 is a response transmitting unit including a modulation circuit 141 and a transmitting circuit 142, and 15 is a holding unit 151A that receives and controls a signal from the individual identification signal detecting circuit 121, and this holding unit (A) 151A. A transmission activation unit including a switch circuit 152 that is controlled to turn on / off the power supply to the response transmission unit 14, 16 is a power supply unit, and 17 is a transmission antenna of the searched station 1. In FIG. 5, reference numeral 21 is a receiving antenna of the search station 2, 22 is a signal generating section including an individual identification signal generating circuit 221, a positioning signal generating circuit 222 and a combining circuit 223, and 23 is a modulating circuit 231 and a transmitting circuit 232. A transmitter provided, 24 is a receiver having a demodulation circuit 241, 25 is a distance calculator having a comparison circuit 251, 26 is a self-position locator, 27 is a position calculation determiner, 28 is a search station transmission antenna, 29 is a position data output terminal for outputting the position data based on the above measurement results, and 30 is distance data for inputting the position information of the other station and the distance data to the searched station when data is provided from the other searched station. An input terminal 31 is a distance data output terminal for outputting position information of the own station when providing data to another search station and distance data to the searched station. The distance data input terminal 30 and the distance data output 3
Example 1 is used in Example 7 of the embodiment. Since this system has a period during which reception is also performed during transmission, in order to simplify the device, the transmission frequency of the search station 2 (= reception frequency of the search station 1) and the reception frequency of the search station 2 (= search station) The transmission frequency of 1) is set separately. Further, FIG. 10 is an explanatory diagram of signals at points where symbols of respective parts are written.

Next, the operation will be described with reference to FIGS. 1, 5 and 10. A signal 101 ((a) in FIG. 10) is a search signal sent from the search station 2 to the searched station 1, and is composed of an individual identification signal 111 and a positioning signal 112. These signals are modulated by the modulation circuit 231 provided in the transmission unit 23, which is generated by the signal generation unit 22 including the individual identification signal generation circuit 221, the positioning signal generation circuit 222, and the synthesis circuit 223 of the search station 2 and then transmitted by the transmission circuit 232. And is transmitted from the transmitting antenna 28 of the search station. Individual identification signal 111
Is a signal for individually designating the searched station 1, and its duration is a predetermined value T1. Positioning signal 1
Reference numeral 12 is a signal used to obtain distance information from the search station 2 to the searched station 1, and is a signal commonly used in this position confirmation system regardless of the individual searched station. The positioning signal 112 is transmitted subsequently to the individual identification signal 111. The duration is a predetermined value T2. The individual identification signal 11 transmitted from the search station 2 in this manner
1 and the positioning signal 112 arrive at the searched station after t / 2 (where t is the round-trip time of radio wave propagation between the searched station and the searched station) has elapsed (b in FIG. 10). This signal is detected by the individual identification signal detection circuit 121 of the designated searched station 1, and the detection signal ((f) of FIG. 10 ... T1a) is stored in the holding section (A) 151A of the transmission starting section 15. When added, the holding portion (A) 151A enters the holding state. As a result, the switch circuit 152 is turned on (holding signal ((g) in FIG. 10 ... Length TH0 = T3), power is supplied from the power supply unit 16 to the response transmission unit 14, the response transmission unit 14 is activated, and the transmission state is set. The duration of the transmission activation is set to the length T3 (≧ T1 + T2) so that the transmission necessary to send back the positioning signal 112 arriving after the individual identification signal 111 can be continued.

Individual identification signal 111 transmitted from the search station 2
When arrives at the searched station 1 ((b) of FIG. 10), the positioning signal 112 is demodulated by the positioning signal demodulation circuit 131 ((c) of FIG. 10). The demodulated positioning signal is modulated by the modulation circuit 141 provided in the response transmission unit 14, amplified by the transmission circuit 142, and sent out to the search station 2 via the transmission antenna 17. This modulated positioning signal 1
12 is received by the receiver 24 of the search station 2 after t / 2 has passed after the station to be searched is transmitted, demodulated ((d) in FIG. 10), and guided to the distance calculator 25.

The distance between the search station 2 and the searched station 1 is determined by the search station 2
Positioning signal 112 (FIG. 10 (e) ... Positioning signal 112 portion in FIG. 10 (a)) transmitted from the operation target station 1
The positioning signal 112 returned to the search station 2 via the
By comparing (d) of 0, it is determined as follows by the time delay information obtained by converting the time delay information or the phase delay information.

As a method of measuring the time delay information, the positioning signal 112 (see FIG. 10) transmitted from the search station 2 is used.
(e)) and the positioning signal 11 returned by the searched station 1
2 ((d) of FIG. 10), a method of directly measuring the delay of the rise time thereof. A method of obtaining phase delay information and converting it to time delay information. There is. As shown in FIG. 10, the positioning signal 112 (shown in FIG. 10) sent from the search station 2 is transmitted.
(e)) reaches the searched station 1 after t / 2 seconds, and the searched station 1
It returns to and arrives at the search station 2 after t / 2 seconds have passed. The former is a method of directly measuring the rise time delay, and the latter is a method of calculating the phase delay between the signal transmitted from the search station and the signal returned at the searched station and converting it into a time delay.

The round trip time from the search station 2 to the searched station 1 is t
If it is second, the distance Lkm is L = 300,000 km × t / 2.

In the method of obtaining the time from the phase difference, the duration of the signal is lengthened and the measurement time is lengthened so that the noise component is averaged and the measurement accuracy can be improved. By utilizing this fact, the duration of the positioning signal 112 is lengthened and the measurement accuracy is improved when the intensity of the arrival signal from the searched station 1 to the searched station 2 is weak. (The configuration of the corresponding searched station 1 is described in the embodiment mode 2)

Next, the Loran system (Long
The self position of the search station 2 at the time of measurement is confirmed by the self position locator 26 using a position confirmation system such as a Range Navigation System) or a GPS system. Then, the searched station 1
The position of is on an arc of radius Lkm drawn centering on the position of the search station in this measurement.

Taking the measurement positions at three points A, B and C, for example, and drawing the arcs a, b and c of the radii Lakm, Lbkm and Lckm obtained from the respective measurement positions as described above, The searched station 1 is located at the cross point X. The position calculation deciding unit 27 decides the position of the searched station based on the distance data from a plurality of measurement positions and the own position data in this way.

Next, the usefulness of this method will be described with specific numerical values. Free Space Propagation Loss: Let us calculate the case where a search station 2 mounted on an aircraft is searching for a search target station 1 drifting over the sea 25 km to -50 km away. If the altitude of the aircraft is maintained at 500 m or more, the range between the search station 2 and the searched station 1 is up to a little over 80 km in terms of radio wave propagation. Therefore, the electric field strength can be calculated as free space in the range of 25 km to 50 km. If the frequency used is 150 MHz, free space propagation loss (at 25 km) -104 dB (at 50 km) -110 dB Propagation characteristics of the route from search station 1 to search station 2: poor conditions "searched station 1 to searched station 2" Compute the propagation characteristics of the "route of". The sensitivity of the receiver of the search station 2 is about 1 uV because the content of the received signal is a simple positioning signal and the duration can be sufficiently long, so the transmission power of the searched station 1 is 10 mW (-20 dBw). In case of, the calculation is as follows, and it can be understood that there is a sufficient margin. Receiving input required for the search station 2 ... 1 uV / 50 ohm = -137 dBw Received input to the search station 2 by transmission of the searched station 1 (calculated value considering only free space propagation loss) 25 km -20 dBw-104 dB = -124 dBw, 50 km -20 dBw-110 dB = -130 dBw This value has a margin of 13-7 dB with respect to the required reception input of -137 dBw. Even considering the loss due to sea surface reflection, etc., it is a sufficient value as a margin and is a value that can be put to practical use. Required battery capacity of searched station 1: Transmission power of searched station 1 10
Assuming that mW is obtained with an efficiency of 30%, the power consumption for transmission is about 30 mW. When the search station 2 calls for 30 minutes after entering the search, and if the time during which the station 1 to be searched actually emits radio waves is about 1/5 = 6 minutes, the battery capacity required for response transmission is It will be 3 mWH. Also, 3V
If it is supplied from a power source, the maximum current is 10 mA, which is extremely small. As described above, the station to be searched 1 is always in the receiving state, and the power consumption is smaller than that at the time of transmitting the positioning signal. Only when specified by the individual identification signal from the search station 2, the searched station 1 activates the response transmission section to perform transmission, so that the battery consumption is extremely small, and the power source is a solar cell, lithium battery, or button. You can use small things such as batteries. Propagation characteristics of the route from the search station 2 to the search station 1: When the transmission output of the search station is 30 W (about +15 dBW), the difference from the transmission power of the search station is 35 dB, so the reception sensitivity of the search station is Even if the reception sensitivity of the search station is lower by about 30 dB (reception sensitivity of about 30 uV), the reception level has a margin of about 5 dB compared with the route from the search target station 1 to the search target station 2. That is, it is possible to cope with a large decrease in the receiving sensitivity due to the downsizing of the searched station side device. Structure of the station to be searched 1, mounting method, etc .: As can be understood from the above description, the circuit elements can be simply configured by ASIC and the like, and the battery capacity can be very small, and the structure is extremely small. it can. Since it can be configured without the need for maintenance, it can be installed, for example, on a built-in life boat holder, a card holder on a helmet for work, or on the chest or shoulders of work clothes. The card holder can be attached with a clevis or directly attached. The above explanation is based on the assumption that the device to be searched is attached to a victim, but even when the position of the stolen vehicle or cargo is to be searched, the device to be attached can be installed so that it is not conspicuous or unobtrusive. In addition to the above requirements, it is necessary to meet the requirements for avoiding transmission of unnecessary radio waves, maintenance-free operation due to minute power consumption, etc., but as described above, the searched side device of the position confirmation system according to the present invention satisfies these requirements. You can

Embodiment 2 FIG. 2 shows the configuration of a searched station 1 according to Embodiment 2 of the present invention. The searched station 1 shown in FIG. 2 and the searched station 2 shown in FIG. 5 are combined to form a position confirmation system according to the second embodiment of the present invention. In FIG. 2, the same reference numerals as those in FIG. 1 indicate the same functions or corresponding portions. Reference numeral 11 is a receiving antenna, 12 is an individual identification receiving section including an individual identification signal detecting circuit 121, 13 is a positioning signal receiving section including a positioning signal demodulating circuit 131 and a positioning signal detecting circuit 132 for detecting a positioning signal, and 14 is a response. The transmitter 15 includes an individual identification signal detection circuit 121 and a positioning signal detection circuit 132.
Holding unit (B) 15 for receiving and holding a signal from
1B and the holding unit (B) 151B, the response transmission unit 1
Switch circuit 152 for controlling power on / off to 4
Is a transmission starting unit, 16 is a power supply unit, and 17 is a transmission antenna. The structure of the holding unit (B) 151B is shown in FIG.
The holding unit (B) 151B includes an individual identification signal detection circuit 121.
Holding circuit 1511 activated by a signal from the OR circuit, and an OR circuit 1512 that ORs the output signal of the holding circuit and the output signal from the positioning signal detection circuit 132.
It is composed of

Next, the operation will be described with reference to FIGS. 2, 5, 6, and 11.
The description will be made based on FIG. What is added to the first embodiment is that a positioning signal detection circuit 132 is added and the transmission start state is maintained by using the detection signal of the positioning signal in addition to the individual identification signal. . When the individual identification signal 111 and the positioning signal 112 arrive from the search station 2, the individual identification signal 111 is detected by the individual identification signal detection circuit 121 and the holding circuit 1 of the holding unit (B) 151B.
In addition, the holding circuit 1511 is held ((h) in FIG. 11 ... Length TH1> T1). Next, the positioning signal 11
2 is detected by the positioning signal detection circuits 131 and 132 ((i) in FIG. 11 ... Length T2a) and is added to the OR circuit 1512, and the signal output from the OR circuit 1512 continues (see FIG.
(J) ... Length TH2)) is output. In response to this, the switch circuit 152 is turned on during TH2, and the response transmission unit 1
4 is supplied with power, and the response transmission unit 14 performs transmission. In this way, the duration of the response transmission on the side of the searched station 1 for each time is automatically set according to the length of the positioning signal 112 when it is long and short when it is short. Utilizing this fact, when the response signal from the searched station 1 to the searched station 2 is weak, the duration of the positioning signal sent from the searched station 2 to the searched station 1 is set to be long, and the positioning signal is automatically detected. The position determination signal sent from the search station 1 to the search station 2 is set to be sent for a long time. As a result, the duration of the positioning signal reaching the search station 2 can be lengthened, so that the influence of noise on the reception of the search station 2 can be reduced, and the measurement accuracy can be improved as described below. Further, when the signal strength from the searched station 1 is strong, the length of the positioning signal is suppressed to the necessary minimum, and the transmission time is shortened to reduce the emission of unnecessary radio waves. By shortening, the battery consumption is reduced. Considering these points, as an example of a method for setting the actual positioning signal transmission time, since the searched station 1 is likely to be far from the searching station 2 at the beginning of the search operation, the positioning signal transmission time is high. It is conceivable that the position signal transmission time is shortened as the position is made closer to the searched station 1. About measurement accuracy How to measure the amount of time delay by comparing the rise times:
Assuming that the s / n (signal-to-noise ratio) of the positioning signal is 40 dB, the noise amplitude ratio (rms) is 1%, so the error caused by the noise of time measurement is about 1% (= 0.6 degree). . This means an error with a radius of about 100 m when measuring 10 km. If s / n is improved, the error caused by noise can be ignored. In the case of the direction detection method of Example 2 and the method additionally described in Example 4 based on the use thereof, there are the following problems. Since the measurement accuracy depends on the symmetry of the shape of the antenna beam, even if s / n is good, the azimuth measurement error appears to be 5 to 6 times as large. If the error caused by s / n is added to this, the error becomes larger. Further, in the measurement of the azimuth angle, a continuous wave is normally transmitted from the measured station and the antenna beam of the measured station is swayed to the left and right to confirm the arrival direction of the signal from the measured station. Since it is extremely difficult to measure the direction when the duration of the signal emitted from the searched station as considered in the present invention is very short, it is considered to be impractical. Method to obtain time delay information by converting from phase delay information:
When signals are continuously integrated, as is well known, signals are integrated by amplitude and noise is integrated by power.
For example, if the integration time is 100 times, the improvement coefficient is 10 (1
The square root of 00 = 10). Compared with the method of directly measuring the rise time, s / n is 20 dB, which is within the same error as in the above calculation. In the method of directly comparing the rise times, the method of integration cannot be adopted because the rising point of the signal is only once for each response transmission, whereas in the method of integrating the phase information, the integration time is calculated by one response transmission. Since the length can be set to an arbitrary length, the improvement coefficient as described above can be obtained.

Embodiment 3 FIG. 3 shows the configuration of a searched station 1 according to Embodiment 3 of the present invention. A combination of the searched station 1 shown in FIG. 3 and the searched station 2 shown in FIG. 5 constitutes a position confirmation system according to the third embodiment of the present invention. In FIG. 3, the same reference numerals as those in FIGS. 1 and 2 indicate the same functions or corresponding parts. 11 is a receiving antenna, 12 is an individual identification receiving section including an individual identification signal detecting circuit 121, 13 is a positioning signal receiving section including a positioning signal demodulating circuit 131, 14 is a response transmitting section, and 15 is an individual identification signal detecting circuit. A holding unit (A) 151A that receives and controls a signal from the 121, and a transmission starting unit that is controlled by the holding unit to turn on / off the power supply to the transmitting unit 14;
6 is a power supply unit, 17 is a transmitting antenna, and 18 is a power supply switch unit. The power switch unit 18 includes a timer circuit 181 that outputs an ON signal at a fixed cycle for a fixed time and an OR gate 1.
82 and a switch circuit 183. The output of the holding circuit (A) 151A is connected to one terminal of the OR gate. As a result, if the output of the timer circuit 181 or the holding circuit (A) 151A is the logical value "1", the switch circuit 183 is turned on and power is supplied to the searched station 1.

Next, the operation will be described. When the timer circuit 181 outputs an ON signal, it becomes a receiving state,
Individual identification signal 1 from the search station 2 when in this receiving state
When receiving 11, the response transmitting section 14 operates similarly to the case of the first embodiment to send back the positioning signal 112 to the search station 2. The position confirmation system according to the present invention transmits the response only when the designation by the individual identification signal is received, so that the power consumption is considerably reduced as compared with the case where it is always transmitted, but the timer is further provided. It performs intermittent reception by using it and thoroughly reduces battery consumption while not being searched. Since the device on the searched station 1 side is normally rarely used, I would like to install a manual power switch and turn off the power, and then switch it on when using it, but then the power switch when it is important There is a risk of human error such as not knowing how to put in or forgetting to put in. Therefore, the power supply circuit is always connected, and the power supply is intermittently turned on / off by an electronic switch to suppress power consumption. The on / off ratio of the intermittent power supply is calculated and set such that when the searched station is a search target, a signal for searching can be accepted during the ON period.
One way of thinking is described below. In this way, even if the power switch is omitted, the power consumption is suppressed to the same level as when the power switch is turned off, the physical power switch is omitted, and the structure is simplified and operated. I try to improve the sex.

From the standpoint of suppressing battery consumption, it is preferable that the off time is long, but the following problems occur. Therefore, the cycle of the intermittent reception on / off time is determined by the following way of example, as an example. The search station 2 continuously sends out the search signal 101 including the individual identification signal 111 and the positioning signal 112 when the search operation is started. On the other hand, since the searched station 1 is operating in the intermittent reception system, it can receive the search signal 101 only intermittently. When the length of the intermittent reception ON time for each time is set to a time at which the search signal 101 can be received three times repeatedly, even if the intermittent reception ON time starts in the middle of the search signal 101, a complete search is performed. The signal 101 can be received at least once without fail. Next, the search station is performing a search while flying at a speed of 200 km / H, and if the search signal 101 can be exchanged with the search target station about 5 times during the time of moving 10 km, 10 km Since the flight time corresponds to 2 minutes, the intermittent reception may be turned on five times during this period, and therefore intermittent reception may be entered once in about 36 seconds. If it is calculated that the duration of each search signal 101 is 1 second, it means that intermittent reception is on for 3 seconds (intermittent reception off 33 seconds) within 36 seconds. However, considering the following circumstances, it is not possible to lengthen the intermittent reception off time.
The reception status of the station to be searched 1 drifting over the sea with large waves changes in the peaks and valleys of the waves, and the electric field weakens in the valleys, so the line construction between the stations to be searched 1 and 2 is established. The probability that you can do it will decrease. If the time from the crest in question to the next crest is about 10 to 30 seconds, the average period of the intermittent reception OFF needs to be about the same. As a further consideration, if intermittent reception is turned on at a fixed cycle, the timing of intermittent reception on and the cycle of rising and falling of the wave will synchronize, and the timing of intermittent reception on will always be the valley of the wave. sell. In order to avoid such a situation, the average interval is set to about 15 seconds, and the timing for turning on the intermittent reception is sequentially changed. For example, if the intermittent reception off time is an integral multiple of 3 seconds and the average is 15 seconds, the longest intermittent reception off time is 30 seconds and the shortest is 3 seconds. As a method of changing the intermittent reception off time, there are a method of gradually increasing (or gradually decreasing) and a method of changing in no particular order. The former has a simple configuration, but if the intermittent reception ON timing is synchronized with the wave trough, there is a problem that it takes time until the intermittent reception is turned ON in the reception condition of the next best condition, that is, the peak of the wave. On the other hand, in the method of changing the intermittent reception off time in random order, since the intermittent reception off time of various lengths is taken on the way, it is possible to deviate from the cycle of rising and falling of the wave in a short time, that is, a good reception state, that is, a wave peak. The intermittent reception is turned on in the part of. One way to achieve this is to use a pseudo-random signal generator with periodicity. As a measure to reduce the decrease in the probability of establishing a line between the searched station 1 and the searched station 2 drifting in the sea with a large wave, the method of changing the intermittent reception OFF timing is described in Embodiment 5, Implementation. Mode 6 will be described.

Fourth Embodiment FIG. 4 shows the configuration of a searched station 1 according to a fourth embodiment of the present invention. A combination of the searched station 1 shown in FIG. 4 and the searched station 2 shown in FIG. 5 constitutes a position confirmation system according to the fourth embodiment of the present invention. In FIG. 4, the same reference numerals as those in FIGS. 1, 2 and 3 indicate corresponding parts or corresponding parts. Reference numeral 11 is a receiving antenna, 12 is an individual identification receiving section having an individual identification signal detecting circuit 121, 13 is a positioning signal demodulating circuit 131 and a positioning signal detecting section 132 for detecting a positioning signal, and 14 is a response signal. The transmitter 15 includes an individual identification signal detection circuit 121 and a positioning signal detection circuit 13.
A holding unit (B) 151 that receives and controls a signal from
B and the response transmission unit 14 controlled by this holding unit (B)
Is a power activation unit for turning on / off the power to the power source, 16 is a power source unit, 17 is a transmission antenna, and 18 is a power switch unit. The configuration of the power switch unit 18 is the holding unit (B) 151B.
FIG. 7 also shows the relationship with. The power switch unit 18 includes a timer circuit 181, an OR gate 182, and a switch circuit 183 that output an ON signal at a fixed cycle for a fixed time. The holding portion (B) 151 is provided at one terminal of the OR gate.
The output of B is connected. As a result, the output of the timer circuit 181 or the holding unit (B) 151B becomes the logical value "1".
In that case, the switch circuit 183 is turned on and power is supplied to the searched station 1. The holding unit (B) 151
The configuration of B is the same as that described in the second embodiment.

The operation of the configuration described above will be described. The same operation as that of the third embodiment is performed in that intermittent reception is performed using a timer, and battery consumption when not being searched is thoroughly reduced. However, once the search signal including the own individual identification signal is received, the response transmission time is lengthened according to the length of the positioning signal, as in the second embodiment. Different from the embodiment.

Fifth Embodiment As mentioned in the third embodiment, "When intermittent reception ON is performed at a constant cycle, the timing of intermittent reception ON is exactly synchronized with the cycle of wave up / down, and the timing of intermittent reception ON. May always be a wave trough. "Therefore, it is necessary to change the timing of intermittent reception ON. This embodiment is an embodiment relating to a solution to this problem. The power switch section 18 uses the one having the configuration of FIG. 8 instead of the timer circuit 181 of FIG. The other points are the same as those shown in FIG. 7. FIG. 8 shows an example of the change-switching type timer circuit 19 in which the switching time of the off period changes as described above. In this example, the change switching timer circuit 19 has four
A cyclic shift register 191 composed of registers (a, b, c, d,) in stages, and an intermittent time setting timer group 192 composed of timer A, timer B, timer C, and timer D
And four AND circuits 1931a, 1931b, 193
AND circuit group 1931 composed of 1c and 1931d, each stage of cyclic register 191 and intermittent time setting timer group 192
Wiring (A) 1932A for connecting each stage of the AND circuit to each AND circuit of the AND circuit group 193 as shown in the figure, and outputs a logical value "1" when any output of each AND circuit is a logical value "1". A logic circuit (A) 193A composed of an OR circuit 1933, and an on-time constant timer 194 that is driven when the output of the logic circuit (A) 193 has a logical value "1" and continuously outputs an on signal for a predetermined time. And a preset circuit 195 that presets the initial state.

FIG. 12 shows the operation of each part of the change-switching timer circuit 19 of FIG. Cyclic shift register 1
91 has one position of the seed signal (logical value “1”), and when the set signal is applied, the value on the cyclic register 191 becomes 1
It is designed to shift in steps (Ra, R in Fig. 12
(B, Rc, Rd thick lines). Each timer of the intermittent time setting timer group 192 outputs a logical value "1" after each set time when a set signal is given.
There are 4 timers here, 4 different times ta, t
Time is set to b, tc, td (TM1, TM2, TM in Fig. 12)
3, the thick line of TM4). Position of seed signal of cyclic shift register 191, and intermittent time setting timer group 19
When the output of any one of the timers 2 of 2 and the position of the logical value 1 "matches, the ON time setting timer 194 is driven through the OR circuit 1933.
When driven by the output of the R circuit 1933, the Qa terminal outputs a signal which is on for a fixed time (Tq). Along with this, the Qb terminal changes from off to on after a lapse of a certain time (signals Qa and Qb in FIG. 12). The ON signal of the Qb terminal is applied to the forward type shift register 191 and the time setting timer group 192 as a set signal. The ON signal of the Qa terminal is input to the OR circuit 182 of the power switch unit 18 to turn on the intermittent reception. In order to gradually increase the time to enter the intermittent reception ON after the pause, set the set time of each timer A, B, C, D of the intermittent time setting timer group 192 to ta, tb, tc, td, and set it gradually longer. Keep it. Assuming that the position of the seed signal of the cyclic shift register 191 is in the register a of the shift register, the logical product output “1” with the signal obtained by the time-out of the timer A drives the on-time setting timer 194 to intermittently receive the signal. turn on. At the same time, the cyclic shift register 191 and the intermittent time setting timer group 192 are reset. Since the position of the seed of the cyclic shift register is moved to the register b, the next intermittent reception is turned on when the output of the timer B which can take the logical product output “1” with the register b is “1”. . Similarly, since the position of the seed of the cyclic shift register shifts every time a clock signal is input, the timing of the intermittent reception OFF changes accordingly. Intermittent reception of the time from the first reset signal to the next reset signal (on + off)
By setting the time to, it is possible to sequentially change the time for turning off the intermittent reception. The timer circuit of FIG. 7 has a constant value for the on time and a constant value for the off time. However, in the present embodiment, the on time is changed to a constant value and the off time is sequentially changed between a minimum value and a maximum value. The difference is that As a result, it becomes possible to secure efficient reception at the peaks and valleys of the waves during the drifting over the sea described in the third embodiment.

Embodiment 6 As the power supply switch circuit 18, the one having the configuration of FIG. 9 is used in place of the timer circuit 181 of FIG. The other points are the same as those shown in FIG. 7. FIG. 6 shows a timer circuit. The difference from the case of FIG. 5 is that a logic circuit (B) 193B connecting between the cyclic shift register 191 and the intermittent time setting timer group 192 is provided in order to change the intermittent reception off time before and after in random order. It is connected as follows. The timer to be activated is specified by the seed signal of the cyclic shift register 191, so that the setting time of the timers specified sequentially is set randomly in each stage of the shift register 191 so that the set times of the timers are random. The register of the cyclic shift register 191 and the intermittent time are set by the order setting logic circuit 193B provided with the wiring 1932B in which the connection method is changed so that the AND between the respective register stages of the timer group 192 is in random order. The timers of the timer group 192 are connected. FIG. 9 shows a case where the change of time changes to ta, tc, tb, td, ta ... In this way, the timer circuit in FIG. 7 has a constant value for the on time and a constant value for the off time, but in the present embodiment, the on time is a constant value and the off time is in any order between the minimum value and the maximum value. It will change as it goes down. This makes it possible to ensure efficient reception at the peaks and valleys of the waves during drifting over the sea described in the third embodiment.

Embodiment 7 By having another search station take over a part of the measurement points and provide the measurement data, the number of measurements can be reduced and the search activity can be carried out quickly. In the configuration of the search station of FIG. 5, the distance data input terminal 30 is a terminal for inputting position information of the other search station and distance data to the searched station when using data of the other search station. When receiving from another search station the position information of the other search station at the time of measurement and the distance data to the searched station, the same method as that of each of the above embodiments is used as a part of its own measurement data. The position of the searched station can be determined by. In the configuration of the search station in FIG. 5, the distance data output terminal 31 is a terminal for outputting position information of the own station at the time of measurement when providing data to another search station and distance data to the searched station. Providing to other search stations the position information of the own station at the time of measurement of the own station and the distance data to the searched station, and using that data as a part of the measurement data of the search station of the provision destination, as in the above-described embodiments. The position of the station to be searched can be determined by the method of.

[0042]

【The invention's effect】

Effect 1 The searched station side device is configured to automatically return the positioning signal from the searched station by individual calling, so that the searched station side can obtain highly accurate information regarding the search, and the searched station side transmits Since only the positioning signal is sent back, there is no erroneous transmission on the searched station side, and the battery consumption is very small.

Effect 2 In the configuration in which the holding circuit is kept held while the positioning signal continues and the length of the response transmission can be changed to the length corresponding to the length of the positioning signal from the searching station, When the reception condition at the station is poor, the positioning signal is lengthened to reduce the influence of noise and improve the measurement accuracy.

Effect 3 In the configuration in which the intermittent reception is performed in which the holding circuit is not operating at a constant cycle, the power consumption can be reduced in the time period when the station to be searched is not searched. There is.

Effect 4 The length of the response transmission can be changed to a length according to the length of the positioning signal from the search station, and the intermittent reception in which the holding circuit is not operated is switched at a constant cycle. With the configuration configured to perform, there is an effect that the power consumption is small but the measurement accuracy can be maintained high.

Effect 5 In the structure in which the intermittent reception is performed during the time period when the holding circuit is not operating and the intermittent reception cycle is gradually changed, the power consumption reduction effect by the intermittent reception is maintained while drifting. This has the effect of making it less susceptible to the wavelength of the waves inside.

Effect 6 Since the intermittent reception is performed during the time period when the holding circuit is not operating and the intermittent reception cycle is changed in any order, the effect of reducing the power consumption by the intermittent reception is maintained while drifting. It has the effect of making it less susceptible to the wavelength of the wave.

[Effect 7] Since a part of the measurement point is taken over by another search station and the measured data is provided, the position of the searched station is calculated and confirmed, so that one specific search station is searched. It is possible to reduce the number of times of measurement of, and it is possible to carry out a search operation promptly.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration content of a searched station according to a first embodiment.

FIG. 2 is a diagram illustrating a configuration content of a searched station according to a second embodiment.

FIG. 3 is a diagram illustrating a configuration content of a searched station according to a third embodiment.

FIG. 4 is a diagram illustrating a configuration content of a searched station according to a fourth embodiment.

FIG. 5 is a diagram illustrating a configuration content of a search station.

FIG. 6 relates to the third embodiment, and includes a holding portion 15
It is a figure explaining the content of 15 of the transmission starting part which has 1B as a component.

FIG. 7 is a diagram related to the fourth embodiment and is a diagram for explaining a configuration content of a power switch unit 18 in relation to a transmission activation unit 15.

FIG. 8 is a diagram related to the fifth embodiment and is a diagram illustrating a configuration content of a sequential change type timer circuit A in relation to a transmission activation unit 15 and a power switch unit 18;

FIG. 9 is a diagram related to the sixth embodiment and is a diagram for explaining a configuration content of a sequential change type timer circuit B in relation to a transmission starting unit 15 and a power switch unit 18;

FIG. 10 is a diagram for explaining signals and timings of each unit in the first embodiment.

FIG. 11 is a diagram for explaining signals and timing of each unit in the second embodiment.

FIG. 12 is a diagram for explaining signals and timings of respective parts in the sequence setting type logic setting circuit A applied to the fifth embodiment.

[Explanation of symbols]

 1 Searched Station 11 Receiving Antenna 12 Individual Identification Signal Receiving Section 121 Individual Identification Signal Detecting Circuit 13 Positioning Signal Receiving Section 131 Positioning Signal Demodulating Circuit 132 Positioning Signal Detecting Circuit 14 Response Transmitting Section 141 Modulating Circuit 142 Transmitting Circuit 15 Transmission Starting Section 151A Hold Part (A) 151B Holding part (B) 1511 Holding circuit 1512 OR circuit 152 Switch circuit 16 Power supply part 17 Transmitting antenna 18 Power supply switch part 181 Timer circuit 182 OR circuit 183 Switch circuit 19 Change switching type timer circuit 1191 Cyclic shift register 192 Intermittent time setting timer group 193A logic logic circuit (A) 193B logic circuit (B) 1931 AND circuit group 1932A wiring (A) 1932B wiring (B) 1933 OR circuit 194 time setting Timer 195 Preset circuit 2 Search station 21 Reception antenna 22 Signal generation unit 221 Individual identification signal generation circuit 222 Positioning signal generation circuit 223 Synthesis circuit 23 Transmission unit 231 Modulation circuit 232 Transmission circuit 24 Reception unit 241 Demodulation circuit 25 Distance calculation unit 251 Comparison circuit 26 Self Position Evaluation Unit 27 Position Calculation Determining Unit 28 Transmission Antenna 29 Position Data Output Terminal 30 Distance Data Input Terminal 31 Distance Data Output Terminal 101 Search Signal 111 Individual Identification Signal 112 Positioning Signal

Claims (7)

[Claims] 1. A position confirmation system comprising a searched station on the searched side and a searched station on the searching side mounted on a mobile body, wherein the searched station is an individual station sent from the searched station. An individual identification signal receiving section equipped with an individual identification signal detection circuit that receives, detects and outputs an identification signal, and a positioning signal receiving section equipped with a positioning signal demodulation circuit that receives and demodulates the positioning signal sent from the search station. (C) a response transmission section including a modulation circuit and a transmission circuit that transmits the positioning signal demodulated by the positioning signal demodulation circuit to the search station, and (d) receives the output signal of the individual identification signal detection circuit. And a holding circuit having a holding circuit for continuing the holding operation for a predetermined time required for sending the positioning signal, and a switch circuit for receiving and transmitting the holding operation signal of the holding unit to start the response transmission section. And a signal generator for transmitting the individual identification signal and the positioning signal, each of which has a transmission time set to a predetermined value, at a measurement point arbitrarily set. To a transmitting section including a modulation circuit and a transmitting circuit for transmitting the transmission signal modulated by the individual identification signal and the positioning signal to the searched station, and the transmission section transmitted from the searched station via the searched station. A receiving unit equipped with a demodulation circuit that receives and demodulates the positioning signal that has returned to the search station, and h) compares the positioning signal obtained by the receiving unit with the positioning signal sent from the transmitting unit and A distance calculation section with a comparison circuit that calculates the distance from the base measurement point to the searched station, a self-positioning section that confirms the self-position of the search station at each measurement point, and Searched from a point Based on each distance information to the search station and self-position information of the search station at each measurement point, a position determination unit that determines the position of the searched station is provided, and each measurement obtained at multiple points. A position confirmation system characterized in that the position of the searched station is determined based on the distance information from the point to the searched station. 2. The position confirmation system according to claim 1, wherein the positioning signal receiving section of the searched station is provided with a positioning signal detecting circuit for detecting a positioning signal in addition to the positioning signal demodulating circuit, and the transmission starting section includes: A switch circuit is provided which is driven by a logical sum signal of the output signal of the holding circuit that receives the output signal of the individual identification signal detection circuit and continues the holding operation for a predetermined time, and the output signal from the positioning signal detection circuit. Characteristic position confirmation system. 3. The position confirmation system according to claim 1, wherein the searched station receives an output signal of a timer circuit that repeats on / off at a predetermined cycle and an output signal of an individual identification signal detection circuit, and performs a holding operation for a predetermined time. A position confirmation system comprising a power supply switch unit including a switch circuit that is on / off controlled by a logical sum signal of the output signal of the holding unit and the output signal of the timer circuit. 4. The position confirmation system according to claim 1, wherein the searched station receives a timer circuit that repeats ON / OFF at a predetermined cycle, and output signals of the individual identification signal detection circuit and the positioning signal detection circuit. A position confirmation system comprising: a holding unit that continues the holding operation for a predetermined time and a power supply switch unit that includes a switch circuit that is on / off controlled by a logical sum signal of the output signals of the timer circuit. 5. The position confirmation system according to claim 1 or 2, wherein the searched station has a timer circuit which is controlled so as to sequentially change an off period, and which intermittently repeats an on / off state, and a predetermined circuit. A position confirmation system including a power supply switch unit including a switch circuit that is on / off controlled by a logical sum signal of an output signal of a holding unit that continues a time holding operation and an output signal of the timer circuit. . 6. The position confirmation system according to claim 1 or 2, wherein the searched station is controlled so that the length of the off period changes in random order and intermittently repeats the on / off state. A power supply switch section including a circuit and a switch circuit that is on / off controlled by a logical sum signal of the output signal of the holding section and the output signal of the timer circuit that continues the holding operation for a predetermined time. Position confirmation system to do. 7. In claim 1, claim 2, claim 3, claim 4, claim 5, and claim 6, the distance measurement is shared among a plurality of search stations including fixed stations, and the measurement data thereof is obtained. A position confirmation system characterized by integrating the position of the searched station.