JP2001356161A - Azimuth information acquiring method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To acquire azimuth information based on the signal transmitted from GPS satellites. SOLUTION: Two GPS(global positioning system) planar antennas 1a and 1b are installed in parallel back to back, signals from GPS satellites are acquired by the GPS receivers 2a and 2b connected to individual antennas, and sky regions 6a and 6b against antenna surfaces where the GPS satellites exist are specified by comparing the acquired signals. The azimuth value in the specific direction of cross lines between the antenna surfaces and the horizontal plane can be instantaneously outputted as an azimuth range with a width by referring to the azimuth values of individual satellites. This device comprises two GPS antennas 1a and 1b capable of specifying the azimuth by the antenna horizontal rotation to the rotation angle upper limit determined by the azimuth range and having opposite semispherical beams, the GPS receivers 2a and 2b connected to the GPS antennas 1a and 1b, a data processing section 3 connected to the GPS receivers in common, and a result output section 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a method for acquiring azimuth information and an apparatus for acquiring azimuth information using GPS satellites.

[0002]

2. Description of the Related Art In this specification, "direction specification" means that a specific azimuth value is uniquely associated with a specific specific direction. For a specific direction, it means to associate a fan-shaped azimuth value range defined by a certain start azimuth value, a certain end azimuth value, and a certain rotation direction. The concept of both directions is included.

[0003] The orientation limitation will be described below. For example, when using a display system in which the frequency increases in the clockwise direction with north set to 0 degrees, an action that uniquely associates a specific direction that is a direction in which a certain mountain can be seen from the user with an azimuth angle of 37 degrees. Is azimuth-specific, while, on the other hand, no information has been obtained, but at least it is certain that it is in a sector that is shown clockwise from azimuth 35 degrees to azimuth 49 degrees. Based on the facts and some information, the behavior to be acquired can be said to be direction limited.

If the azimuth limitation can be performed very quickly as compared with the azimuth specification, it can be said that the azimuth limitation action has practical utility. If practicable, both azimuth limitation and accurate azimuth identification are possible, the practicability is even higher. That is, when priority is given to accuracy, azimuth identification may be performed, and when priority is given to speed, azimuth limitation may be performed.

In fact, in view of the specific situations described below, it is recognized that both the direction specification and the direction restriction are necessary.

For example, a visually impaired person walking outdoors, or a mountain climber who is obliged to walk in a mountainous or mountainous area where visibility is ineffective due to heavy fog and snowstorms.
Consider a reconnaissance operator. For those in the situations mentioned here, they have to walk in a state corresponding to the neglected world,
The fact is common. Of course, the latter should be temporarily encamped, but the prediction of the danger of life at extremely low temperatures after sunset, or the prediction of danger to the body and life from the forecast of storm snow, together with accurate situation judgments In this case, there is a case where a person makes a certain action decision and walks even in the neglected world. This neglected walking has the following common features.

First, it is often good that a portable satellite positioning device can determine a current position by latitude and longitude values, and a destination is also apparent by latitude and longitude values, so that an azimuth value toward a destination can be obtained as a result. However, since the ignoring field is equivalent to depriving a simple visual directional information acquiring function, if there is no other directional information acquiring means,
The azimuth values can hardly be used effectively for action decisions. On the other hand, the result may be largely deviated due to disturbance magnetism depending on the place of use, and a compass which cannot output the deviation, that is, the error width, cannot be used for important decisions such as determining the direction of neglect field walking. Latitude, longitude, altitude, GP based on signals transmitted from GPS satellites
The direction information such as S time was easily obtained, but the direction information was not obtained. For land mobiles, a suitable method for calculating the direction of movement by repositioning by moving is GPS (Global P
Due to the positioning error of the ositioning system (one of the satellite positioning systems), a considerable walking distance is required, and even a visual walk is a heavy load, and it is extremely difficult to implement it in a neglected walk. Therefore, even if you bring a portable satellite positioning device, but do not provide the bearing, the device does not provide a bearing. Function was insufficient. A direction information acquisition method that can compensate for this is needed.

Second, even if it is possible to decide to proceed in a specific direction in some way, humans generally use a visually recognized direction such as a specific feature direction or celestial object direction. Since the straightness is maintained by the feedback loop that finely corrects the traveling direction of the vehicle, it is difficult to maintain the traveling direction correctly in the negligible situation.
As in the case of walking with closed eyes, if the azimuth is not checked frequently, the course is curved contrary to the initial intention, and there is a danger of stepping into a dangerous area such as an avalanche-prone area, for example. . In this case, since the direction is checked very frequently, the work load is large for each checking operation, and if it seems that the behavior is restricted, it is useless in practice. It is indispensable for a person who performs neglect field walking to have a quick direction information acquisition method that can be easily operated while continuing walking and is suitable for frequently acquiring information.

Thirdly, when vision is not used, it is necessary to constantly search for obstacles using a hand or a stick which is an extension of the hand to detect an obstacle ahead, and to avoid falling down. Therefore, even if there is a device related to the above-mentioned direction identification and direction limitation, a hand-held device is inappropriate, and a wearable type device should be used so as not to restrict the detection of a forward object by a hand or a cane during neglect walking. The device is suitable.

[0010] From the above, the following features are required to properly support neglect walking. First, it is equipped with a function to limit the direction, which has the speed and simplicity of measurement and can clearly indicate the degree of error, so that it is often possible to confirm that the traveling direction does not deviate from the intended direction during neglecting field walking. It is necessary. Secondly, it is necessary to have a somewhat accurate direction identification function that can determine the walking direction to the destination point when the latitude and longitude values of the local point and the destination point can be obtained when walking in the neglected field. Become. Thirdly, when walking in the neglected field, the hand is an important means for detecting a forward object and avoiding falling, so that a device which can be directly attached to a body or clothing is suitable.

[0011]

That is, in addition to supporting the daily outdoor activities and outdoor activities of the visually impaired, it is also necessary to obtain orientations that are useful in the field activities of healthy people under weather conditions with poor visibility. The requirements are as follows: (1) Direction can be limited immediately (useful for frequently checking straightness in the process of ignoring walking). (2) Direction can be easily specified with the same device (helping to specify the direction of travel at the start of neglect walking). (3) It can be used while being worn on the body because it is small and light and has a plane configuration that follows the body (does not block hands that are important in the process of neglecting walking). More specifically, it has the following practical features. (4) It can take on a shape that is visually acceptable even when the visually impaired person always wears it and uses it in the social life scene (it can support the social life of pedestrians who are routinely neglected). (5) The measurement direction always matches the direction of the face to which the observer is currently facing, so it is intuitive and easy to use (the direction acquisition operation is easy enough to withstand frequent use in the process of neglect field walking). (6) It can be built relatively inexpensively by making small modifications using the component parts of conventional portable satellite positioning equipment (the support for neglecting walking itself is not very expensive). (7) Since it has a satellite positioning function, it is not necessary to separately carry a satellite positioning device (it is possible to reduce the number of items required for the process of walking in the neglected field).

The present invention has been made in view of the above circumstances, and has as its object to provide a method and an apparatus for acquiring azimuth information which can be performed immediately by azimuth limitation and azimuth specification and which can be easily carried.

[0013]

An azimuth obtaining method according to the present invention comprises a pair of azimuth antennas each having a hemispherical antenna pattern.
GPS antennas are placed vertically on the ground, facing each other,
With one major circle passing through the zenith as a border, the GPS antenna forms an overlying area where the sensitivity of the antenna extends to a quarter celestial sphere in the direction in which the GPS antenna is facing, and receives GPS signals connected to each antenna. The GPS satellites from all GPS satellites in the hemisphere and compare the reception status of each GPS satellite signal with both GPS receivers to determine the area where one or more GPS satellites exist. Index, take out the GPS satellite azimuth from at least one GPS receiver, create a sequence of satellite azimuths in each area clockwise, extract the first azimuth and the last azimuth, and extract at least The azimuth is limited by the azimuth of the first term and the azimuth of the last term obtained in one area.

Further, in the azimuth obtaining method according to the present invention, a pair of GPS antennas each having a hemispherical antenna pattern are arranged perpendicularly to the ground in a direction opposite to each other and pass through the zenith.
With two major circles as the boundaries, the GPS antenna forms the sensitivity of the antenna and the sky coverage area in the sky sphere in the direction in which it faces, and is connected to each antenna.
Have the GPS receiver attempt to capture the signals transmitted from all GPS satellites in the hemisphere, and determine the area of one or more GPS satellites by comparing the GPS satellite signals from both GPS receivers. Extracting the GPS satellite azimuth from at least one of the GPS receivers, creating a sequence of satellite azimuths clockwise in each region, extracting the first azimuth and the last azimuth, and extracting at least The azimuth is limited by the azimuth of the first term and the azimuth of the last term obtained in one region, and the angle width of the obtained azimuth is set as the upper limit of the rotation angle, and the pair of GPS antennas is horizontally rotated, Let the GPS receiver connected to each antenna attempt to capture the signals transmitted from all GPS satellites in the hemisphere above the sky, and determine from the obtained signals of each GPS satellite that at least one satellite exists at the boundary. In the direction that led to the judgment Serial stops the horizontal rotation of the pair of GPS antennas, at least performs existence region determination of another one of the GPS satellites, take out the azimuth angle of the satellite from at least one of the GPS receiver was removed above 1
The azimuth is specified by comparing the azimuth of one satellite, the azimuth in the opposite direction, and the azimuth of the satellite determined to be present at the boundary.

[0015] The method includes using a planar patch antenna as the pair of GPS antennas.

[0016] The pair of GPS antennas may be attached to each other with their head or body sandwiched therebetween, facing backward and parallel to each other, and perpendicular to the ground.

Furthermore, the azimuth information acquiring apparatus according to the present invention is characterized in that:
A GPS antenna having a pair of hemispherical antenna patterns that are arranged parallel to each other, facing each other and vertically, and each of the GPS antennas has an antenna cover in which the antenna sensitivity extends to a quarter celestial sphere above the direction in which the GPS antenna faces. Forming a zone, means for capturing signals transmitted from satellites existing in the respective overlying areas by the pair of antennas, and creating a series of satellite azimuth angles clockwise in each of the areas, Means for extracting the azimuth and the azimuth of the last term, means for determining the existence area where the satellite was present from comparison of the signals from each captured satellite, and at least one of the above areas obtained Means for limiting the azimuth by the azimuth of the first term and the azimuth of the last term;
Characterized by comprising:

Further, the azimuth information acquiring apparatus according to the present invention comprises:
A GPS antenna having a pair of hemispherical antenna patterns which are arranged parallel to each other, facing away from each other, and vertically arranged, and each of the GPS antennas covers an upper quarter of the sky in the direction in which the antenna is directed. Forming a means for capturing signals transmitted from the satellites existing in the respective overlying areas by the pair of antennas, and comparing the signals from the respective captured satellites to determine the existence area where the satellites were present. Means for determining, a series of satellite azimuth angles in each of the above regions in a clockwise direction, and means for extracting the azimuth angles of the first azimuth angle and the last azimuth angle. Means for limiting the azimuth by the obtained azimuth angle of the first term and the azimuth angle of the last term, means for horizontally rotating the pair of antennas with the obtained angular width of the azimuth as the upper limit of the rotation angle, Spinning one Attempt to capture signals transmitted from all GPS satellites in the hemisphere above the antenna, and from the obtained signals of each GPS satellite, it was determined that at least one satellite was present at the boundary. Means for stopping the horizontal rotation of the pair of antennas, means for determining the presence area of at least one other GPS satellite, and means for extracting the azimuth of the satellite; Means for identifying an azimuth by comparing the azimuth of the satellite determined to be present at the boundary with the azimuth. Characterized by comprising:

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to the accompanying drawings, an embodiment of an azimuth information acquiring method and an azimuth information acquiring apparatus embodying the same according to the present invention will be described in detail.

In the following description, the unit of the angle is degree (d
Using eg), use the azimuth display of 90 degrees east, 180 degrees south and 270 degrees west in the clockwise direction with north set to 0 degree. As the elevation angle, an elevation angle display in which the horizontal plane is 0 degree and the zenith is 90 degrees is used.

First, the principle of obtaining the azimuth limitation according to the present invention will be described with reference to FIG. A first planar patch antenna 1a and a second planar patch antenna 1b are provided at the center of FIG. The first planar patch antenna 1a and the second planar patch antenna 1b are arranged in a rearward direction and parallel to each other. And both are installed perpendicular to the ground. At this time, if the first plane patch antenna 1a is arranged on the left side and the second plane patch antenna 1b is arranged on the right side, if the antenna arrangement is viewed from above while standing on the ground, for this observer looking down, The direction in front of the body is hereinafter referred to as measurement direction 5.

As the first and second planar patch antennas 1a and 1b, those having a hemispherical beam pattern with respect to right-handed circular polarization used in the GPS satellite system are used. In rare cases, some documents describe an antenna pattern with a hemispherical beam as omnidirectional, but omnidirectional is exactly the meaning of isotropic. Omni-directional, that is, according to the usage to be isotropic,
It is not used for describing a hemispherical beam pattern. Since the first and second planar patch antennas 1a and 1b are set up vertically to the ground, half of the hemispherical beams are directed to the ground and are not used. And the other half has sensitivity to the sky.

When such two planar patch antennas are made to face each other and are parallel to each other, and when they are set up perpendicularly to the ground, each of the first planar patch antenna 1a and the second planar patch antenna 1b is substantially The upper cover area, as shown in FIG. 1, corresponds to a state in which the sky is divided into two parts with a major circle as the arc of a great circle as a boundary. The majority of the circle is the area 6a covered by the first planar patch antenna 1a and the second planar patch antenna 1a.
Most circle 7 is the boundary of the sky coverage area 6b by b. In other words, the first planar patch antenna 1a is the GPS satellite A in FIG.
The second plane patch antenna 1b covers a quarter celestial sphere above the GPS satellite B in FIG. 1 where the GPS satellite B in FIG. 1 exists.

Since the positioning radio wave transmitted from the GPS satellite uses a microwave frequency band around 1.5 GHz, the positioning radio wave has excellent straightness like light, and the first plane patch antenna 1a for GPS uses The signal intensity from the GPS satellite A in the overlying area 6a and the G not in the overlying area 6a of the first planar patch antenna 1a
There is a clear difference in the signal strength from PS satellite B. Therefore, based on the difference between the signal intensities, the existence areas of the GPS satellites A and B can be determined. Based on the existence area of each GPS satellite and the azimuth information of each GPS satellite, the measurement direction 5 can be determined.
Can be limited in direction.

In FIG. 1, the GPS satellite C is located in a majority circle 7 which is a boundary between the upper area 6a covered by the first planar patch antenna 1a and the upper area 6b covered by the second planar patch antenna 1b. Therefore, the signal from the GPS satellite C is received by the first planar patch antenna 1a and the second planar patch antenna 1b. Since the orbit of the GPS satellite system is as far as about 20,000 km above the sky, electromagnetic waves arriving from the far field
The incident light enters the coverage areas 6a and 6b of the two planar patch antennas 1a and 1b in parallel, and is received by both. In the present invention, when the signals are received simultaneously in this manner, the direction in which the GPS satellite C is
Or, it can be determined as an anti-measurement direction, which is a direction obtained by adding 180 degrees to the measurement direction 5, and the GPS satellite A described above
And the azimuth information of GPS satellite B and the result of area determination,
The direction of measurement direction 5 can be specified.

The major features of the planar patch antenna used for obtaining the azimuth information are that it is small and lightweight, easy to manufacture, and can be manufactured at low cost. In actuality, when the first planar patch antenna 1a and the second planar patch antenna 1b are created, a three-dimensional space slightly larger than the hemisphere, which is a circularly polarized beam width calculated theoretically assuming an infinite ground plane at the time of design. In some cases, a planar antenna having a circularly polarized beam width with respect to an angle is completed. This is due to the fact that the actual design is different from the result of designing with an infinite ground plane as the theoretical calculation. This is specified in the following document.

Published by the Institute of Electronics, Information and Communication Engineers, "Small and Planar Antennas", edited by Misaki Haneishi, Kazuhiro Hirasawa, and Yasuo Suzuki, first edition published on August 10, 1996, P100.

Global Positioning System: Theory and
Applications Volume I Edited by Bradford W. Parkins
on and James J. Spilker Jr. Published by the Ameri
canInstitute of Aeronautics and Astronautics, Inc.
1996, P342-P343, P722.

It is known as antenna pattern shaping that such a deviation of the beam shape is corrected while slightly changing the substrate size and the patch size to obtain a desired antenna pattern.

However, in the case where the beam has a solid angle shape slightly wider than desired, the beam may be used as it is in the present invention. Then, most of the circles in FIG. 1 are not lines, but rather a band region having a slight minute width (having a slight viewing angle when viewed from an observer). If the viewing angle width is not too large, there is no problem in practical use. In the azimuth limitation function described in detail later, this slight spread produces a minute width in the measurement direction 5, and has the effect of increasing the probability of accidentally acquiring a satellite.
On the other hand, with the azimuth identification function, it is expected that the accuracy at the time of azimuth identification will slightly decrease, but there is no major problem in practical use as the object of the present invention, and the fact that there is some tolerance is considered from the viewpoint of manufacturing cost. preferable.

Alternatively, unlike the calculation at the time of designing the semi-celestial sphere, if the fabrication result has a beam larger than the semi-celestial sphere, a shielding material made of a radio wave shielding material may be arranged on the back side to remove unnecessary sensitivity portions. A semi-celestial sphere beam antenna can be easily constructed.

Next, an embodiment of an azimuth information acquiring apparatus embodying the azimuth information acquiring method according to the present invention will be described with reference to FIG. In FIG. 2, a first planar patch antenna 1a
Is connected to a first GPS receiver 2a, and the second planar patch antenna 1b is connected to a second GPS receiver 2b. In addition,
As described above, the first and second planar patch antennas 1a and 1b are in a state where they are opposed to each other and parallel, and both are set upright to the ground.

The first GPS receiver 2a and the second GPS receiver in FIG.
The functions and specifications that should be possessed by 2b may be equivalent to those of GPS receivers for small portable positioning devices using L1 waves that are widely used. In other words, the compactness and mass production cultivated when the consumer GPS positioning device is reduced in size and weight is inherited and used. Consumer GP
In order to reduce the size and weight of S positioning devices, there are already many GPS receivers that are large enough to fit a flat patch antenna. Alternatively, it can be easily manufactured. Also, with a planar patch antenna
The GPS receiver is integrated into the housing, and even if both are combined, small ones that fit easily in the palm of the hand already exist at low cost, and there is no problem as a manufacturing technology. Since the existing accumulation of miniaturization techniques can be used, the present invention can be economically and miniaturized.

The GPS receiver outputs the next data string at a cycle of, for example, every second or less, that is, a GPS receiver having a standard specification is used. The data contained in the output is as follows. First, the current time, and, as positioning data, latitude, longitude, altitude, positioning calculation time, positioning calculation mode (2 using three satellites)
Indicates the three-dimensional positioning or three-dimensional positioning using four satellites), and the satellite number assigned to channel 1, the satellite elevation angle,
Satellite azimuth, channel status, satellite number assigned to channel 2, satellite elevation, satellite azimuth, channel status,
…, Satellite number assigned to channel n, satellite elevation angle,
Satellite azimuth, channel state. The number of channels n is usually
12 are used. This can be synchronized with signals of 12 satellites in parallel, and can be said to be the current standard specification. According to the present invention, these popular and inexpensive portable L1 wave GPS receivers and planar antennas can be used almost as they are.

The first GPS through the first planar patch antenna 1a
The receiver 2a attempts to synchronize / decode the satellite signal and attempts positioning. Similarly, the second GPS receiver 2b attempts to synchronize and decode the satellite signal through the second planar patch antenna 1b, and further attempts to position. That is, the first GPS receiver 2a, the second GPS receiver
In 2b, like the GPS receiver of the ordinary portable satellite positioning device,
It performs a signal search for all GPS satellites that are expected to be in the sky, just as if they were connected to an antenna covering the hemisphere over the sky.

It should be noted that radio waves transmitted from GPS satellites
It also contains GPS satellite orbit information (almanac data), which is transmitted from all satellites. For this reason, although it exists in the sky above the elevation angle of 0 degrees from the current position, it is synchronized with the signal because the signal is blocked by the shielding of the feature or terrain, or it is not in the antenna coverage area The elevation and azimuth for GPS satellites that are not able to
It can be calculated and output from the data received from the satellite by simple calculations. In fact, there are devices that output such information.

Also, all GPS satellites transmit signals at exactly the same frequency, but the spread spectrum due to the pseudo noise code
(Spread Spectrum) Since the technology of the communication method is used, there is no possibility of interference even if the same frequency is used. By assigning a different sequence of digital codes, called pseudo-noise codes, where 0s and 1s alternate at first glance, a different array is assigned to each GPS satellite, so that signals from each satellite can be identified and separated and received. That is, for all GPS satellites that are present at an elevation angle of 0 degrees or more from the current position, not only their elevation angles and azimuths in the sky, but also
In principle, it is easy in principle to separate and detect the establishment / non-establishment of synchronization with the signals from these satellites, that is, the reception state.

In the process of causing the GPS receiver to search for a signal,
The satellite number, satellite elevation angle, satellite azimuth, and channel state of the GPS satellites, which are data of each satellite, are periodically output from both GPS receivers. Further, the positioning result data such as latitude, longitude, altitude, positioning calculation time, positioning calculation mode, and current time are periodically output from both. Note that the cycle of outputting data is not particularly limited, and GPS receivers of about every second are now widespread. Is also good.

Each data obtained from the first GPS receiver 2a and the second G
Each data obtained from the PS receiver 2b is input to the data processing unit 3. The data processing unit 3 processes these data as follows.

The data processing unit 3 first constructs a data table for acquiring azimuth information for the data of each satellite. The positioning result data is stored in a buffer of the data processing unit 3, provided for the purpose of reference necessary for completing the data table, and then notified to the result output unit 4. Each row in the data table for acquiring azimuth information corresponds to each GPS satellite. It is assumed that the maximum number of rows in the data table is equal to the maximum number of satellites that can be processed by the first GPS receiver 2a and the second GPS receiver 2b in parallel. Here, the maximum number of satellites that can be processed in parallel by the first GPS receiver 2a and the second GPS receiver 2b is assumed to be the same as that of a portable positioning device currently in practical use at the citizen level, and is assumed to be 12.

Each column of the data table has the following items. 1
In the column, the satellite number is recorded periodically. 1st GPS receiver
There is an input from 2a and an input from the second GPS receiver 2b,
These values can be considered the same. If they are not the same,
There are more than 12 satellites in the sky, and the first GPS receiver 2a and the second GPS receiver 2b are trying to acquire different sets of satellite numbers. Or, either uses old almanac data. Therefore, the data processing unit 3 detects the set of satellite numbers selected by the GPS receiver sending the new positioning calculation time information, and instructs the other GPS receiver to select that satellite. Send. The function of designating a set of satellite numbers for signal acquisition is also a common specification in the GPS receiver of the portable satellite positioning device.

The second column stores the satellite azimuth and updates it periodically. The third column stores the satellite elevation and updates it periodically. Regarding the values in the second and third columns, there is an input from the first GPS receiver 2a and an input from the second GPS receiver 2b, but these values can be regarded as the same. If not identical, either GP
Since the S receiver is acquiring the latest almanac data from the satellite and using slightly older almanac data, the solution is to adopt input from a GPS receiver that is sending newer information about positioning calculation time I do.

Here, the information on the elevation angle is examined, and the data of the GPS satellite with an excessively high elevation angle is removed so as not to be used in the subsequent processing. Satellites in the third row with a very high elevation angle (close to the zenith) have a slight difference in their azimuth angles, but they are very small as actual separation angles, and are used as the basis for calculating azimuth information. It is not preferable. Therefore, for example, it is assumed that a satellite having an elevation angle of 85 degrees or more is not used for acquiring subsequent direction information. In the sixth column, note that as a result of the inspection, the satellite was rejected as a high-elevation angle satellite. When the elevation angle changes and it is no longer necessary to eliminate it because of a high elevation angle, the symbol can be cleared.

The fourth column periodically stores the channel state obtained by the first GPS receiver 2a. The fifth column stores the channel state obtained by the second GPS receiver 2b. These values indicate whether they are synchronized or not.

The signal transmitted from the GPS satellite uses a pseudo-random noise (PRN) having a code length of 1023 because it uses a technology called a spread spectrum communication system using a pseudo-noise code. ) Code. The PRN code is a unique identification code uniquely assigned to each GPS satellite. Therefore, in the channel inside each GPS receiver, the PRN of the satellite
Synchronization is performed by generating the same replica pseudo-random noise as the code. If this synchronization is achieved, the weak spread signal buried in the noise becomes an extremely strong signal (increases by about 40 dB when synchronization is established) and can be identified and detected. Therefore, it is normal that the reception is established when the establishment of the synchronization is confirmed.

Here, shielding by a feature or topography will be examined.
Even if the satellite is in the area covered by one of the antennas, if the line of sight propagation is shielded by terrain, artificial structures, or trees, the signal strength will be extremely low and the receiver Cannot detect synchronization. Therefore, when the channel states of the receivers of both antenna systems do not indicate synchronization, it is highly likely that the satellite is shielded by terrain or terrain. Such satellite information is excluded so as not to be used for calculating the azimuth information. In the sixth column, the result of the exclusion judgment due to this feature shielding or terrain shielding is described. Of both antenna systems
When the condition that both the channel states in the GPS receiver do not indicate synchronization is canceled, this symbol may be canceled.

The above-mentioned two exclusion judgments, that is, a high elevation angle judgment,
Alternatively, rearrangement is performed by using the satellite azimuth data in the second column for the satellites other than those excluded by either the feature / terrain occlusion determination. Here, the azimuth notation method is used in which the numerical value rises clockwise with north as 0 degree, so if ascending sort is used, the satellite azimuth will be the order of the satellite azimuth in the clockwise direction with the north as the base point. Line up.

The fourth column, that is, the first signal strength, and the fifth column, that is, the second signal strength are each compared with the above-mentioned threshold value to determine the satellite existence area. The channel status of the GPS receiver of one antenna system indicates synchronization, and the channel status of the other antenna system indicates synchronization.
If the channel condition of the GPS receiver does not indicate synchronization, the satellite can be determined to be within the coverage of the former antenna. In this case, in the seventh column, the number of the former antenna, that is, the first GPS
For the receiver 2a, "1" is stored, or for the second GPS receiver 2b, "2" is stored. Next, when the channel states of the GPS receivers of both antenna systems are both equal to or greater than the threshold value, the satellite is almost on the circle (including the zenith) where the extension of the antenna facing surface intersects the sky hemisphere. In the seventh column is a number that represents it "
Stores 0 ".

With the above procedure, the data processing unit 3 can construct a data table.

Here, the data processing unit 3 calculates the satellites in the seventh column, excluding the excluded satellites shown in the sixth column of the data table.
That is, the region determination result is read from top to bottom. Since the azimuths have already been sorted in ascending order, it is substantially equivalent to reading out the area determination result of the satellite in ascending order of the azimuth angle when considered clockwise starting from the north.

As a result, a sequence having elements 0, 1, and 2 is generated. The last term in this sequence follows the first,
It forms a directional circular arrangement (hereinafter referred to as R). Since the azimuth angle is 0 degrees and 360 degrees coincidence and returns to the original, the azimuth is aligned in this order, and the last term of the sequence is assumed to be the continuation of the first term, and the directional ring is By configuring the target arrangement, the ordering based on the azimuth can be maintained. This internal structure of R will be important later.

The data processing unit 3 simply inspects the internal structure of R, and branches the process into three based on the result.

Here, three finite number sequences are defined below for the purpose of simply describing a number sequence which is a partial structure inherent in R.

S0 indicates that “the number of terms is one or more, and all terms are numbers“ 0 ”
Is a finite sequence "(eg, {0, ..., 0}).

S1 indicates that the number of terms is one or more, and all terms are numbers "1".
Is a finite sequence "(eg, {1, ..., 1}).

S2 indicates that “the number of terms is one or more, and all terms are numbers“ 2 ”
Is a finite sequence "(eg, {2, ..., 2}).

By utilizing these definitions, the determination of the internal state of R is simply expressed.

The sequence of terms in R is replaced by using S0, S1, and S2.

In rare cases, two S0s (or more) within R
If so, one of them is named S0 '.
However, S0 ′ is defined as “a finite sequence having at least one term and all terms having the number“ 0 ”” (eg, {0,..., 0}).

Regarding the state of the internal structure of R, all cases are exhausted in the following state A, the next state B, and the other state C.

That is, the state of R is state A, which means that “in terms of the internal structure of R, the number of sequences S0 and S0 ′ is 0, and the number of each of sequences S1 and S2 is 1 or less. Both are not zero at the same time. "

Next, the state of R is state B is defined as "R
, The number of the sequence S0 is one, and the sequence S0 ′
Is 1 or less, and the numbers of the sequence S1 and the sequence S2 are 1 or less and not 0 at the same time. "

Next, the state of R is the state C, which means "R
Is neither the state A nor the state B. "

The number of each sequence in R is represented by (S0, S
0 ', S1, S2) in parentheses. Then, the internal state of R can be represented in detail.

When R is in the state A, using the above notation, R is (0,0,0,1), (0,0,1,0), (0,0,1,1 ) Indicates any of the cases.

When R is in the state B, using the above notation, R becomes (1,0,0,1), (1,1,0,1), (1,0,1,0). ), (1,1,1,
0), (1,0,1,1), or (1,1,1,1).

When R is in the state C, using the above notation, R becomes (0,0,0,0), (1,0,0,0), (1,1,0,0). ), Or any of the four numbers contains more than one number
(For example, (1,0,2,1)).

In particular, only two of these cases appear in reality. The most frequently appearing case is contained in state A, but in the case of (0,0,1,1). The frequency of this case is overwhelmingly high. Next, the occurrence frequency of the case (1,0,1,1) included in the state B can be seen to some extent. The former case (0,0,1,1) is the most common case of orientation limitation. The latter (1,0,1,1) case is the most common case of bearing identification. Usually, the total occurrence frequency of these two cases is 100%. The probability of occurrence in other cases in normal use is almost 0%. When these exceptional events appear, it is presumed that the sky is not open at all, or that half of the sky is artificially blocked.

The first term and the last term in each sequence are determined by the azimuth order appearing clockwise in the corresponding area.

As examples, there are several cases which have a low probability, but which should be specified in the method of determining the first term and the last term.

In the rare case where there is nothing other than one S1 in R (0,0,1,0), the method of determining the first term and the last term of S1 is as follows. If the number of terms in S1 is 1, the above satellite is S1
First term = last term of If the number of terms in S1 is 2 or more,
Create circular permutations for satellite azimuths. If the azimuth of a certain satellite and the azimuth of the next satellite clockwise constitute 180 degrees or more, the above-mentioned certain satellite is regarded as the last term of S1, and the succeeding satellite is regarded as the first term of S1. , And the other terms are terms defined in the order when the circular permutation of the azimuth is viewed clockwise from the first term.

Although this is also rare, if there is nothing other than one S2 in R (0,0,0,1), how to determine the first and last terms of S2 is as follows . If the number of terms in S2 is 1, the above satellite is defined as the first term of S2 = the last term. If the number of terms in S2 is 2 or more, a circular permutation is made for the satellite azimuth. If the azimuth of a certain satellite and the azimuth of the next satellite clockwise constitute 180 degrees or more, the above-mentioned certain satellite is regarded as the last term of S2, and the immediately succeeding satellite is regarded as the first term of S2. , The other terms
The terms defined in the order when the circular permutation of the azimuth is viewed clockwise from the first term.

In a rare case, if there is nothing other than S0 in R (1, 0, 0, 0), the following processing is continued. If the number of terms in S0 is 1, then that term is defined as the first term of S0 = the last term. If the number of terms in S0 is 2 or more, the following processing is performed. Create a circular permutation for the satellite azimuths of the satellites belonging to S0. The angle between the azimuth of a certain satellite (A) and the azimuth of the next satellite (B) in the clockwise direction is 170 ° or more and 190 ° or less, and the angle of a certain satellite (C) is If the azimuth angle and the azimuth angle of the next satellite (D) in the clockwise direction are 170 degrees or more and 190 degrees or less, A is the last term of S0, B is
Is the first term of S0 ', C is the last term of S0', D is the first term of S0, and the other terms are in the order in which the circular permutation of the azimuth angle is viewed clockwise from the first term. This is a prescribed section. Now (1,0,
Some of what looked like (0,0), which should be (1,1,0,0), were properly handled.

From the above discussion, the first term and the last term can be appropriately selected in all cases.

For the purpose of simply describing the flow of azimuth limitation and azimuth specification, the satellite azimuth will be defined below. A (S
1, 1) is defined as the azimuth of the satellite in the first term of the sequence S1. A (S
1, e1) is defined as the azimuth of the satellite at the end of the sequence S1. A
(S2, 1) is defined as the azimuth of the satellite in the first term of the sequence S2. A
(S2, e2) is defined as the azimuth of the last satellite in the sequence S1.
A (S0, m0) is defined as the azimuth of the satellite in the central term of the sequence S0. However, the central term is defined as the term of “the smallest integer not less than a value obtained by dividing the number of terms by 2”.

The outline of the subsequent processing will be briefly described first from a large viewpoint. When R is in state A, the direction can be limited. In state B, the direction can be specified. In state C, the observer is informed that the method of use is not appropriate, and prompts a simple response (turning at 90 degrees or use in a view with a good view in the sky). It will be described later that the probability of occurrence of state C is extremely low.

Now, the first case of three branches using the state of R as a branch condition will be described. R is inspected by the data processing unit 3, and as a result, if the state of R is the state A, the measurement direction 5 can be regulated under two conditions. Can be limited. That is, assuming that the azimuth angle of the measurement direction 5 is z, the data processing unit 3 determines as follows.

The first direction information that can be obtained in the case of the state A is as follows. If the sequence S1 exists, the sequence S1 is defined as the starting azimuth with the satellite azimuth associated with the last term of S1.
In the azimuth region defined in the clockwise direction, with the opposite direction of the satellite azimuth associated with the first term of the terminal terminating azimuth,
An azimuth angle (z) in the measurement direction exists.

The second direction information that can be obtained in the case of the state A is as follows. When the sequence S2 is present, the start direction is the reverse direction of the satellite azimuth angle associated with the end term of S2, and the end direction is the satellite azimuth angle associated with the first term of the sequence S2. The azimuth angle (z) in the measurement direction exists in the azimuth angle region.

From the intersection of the above two azimuth information, the data processing unit 3 can immediately limit the azimuth range of the measurement direction 5 (without rotation).
The result of the direction limitation is notified to the result output unit 4.

The following is the description in virtual code.

[0082]

(Equation 1)

Note that the notation a <b <c indicates that the azimuths a, b, and c appear clockwise in the order of a, b, and c. That is, the relationship indicates that a certain azimuth angle b exists in an azimuth angle range defined clockwise by the start azimuth angle a and the end azimuth angle c.

Next, the procedure when the state of R is B will be described.

The data processing unit 3 checks R, and
As a result, when the state of R is the state B, in the following procedure,
The direction of measurement direction 5 can be specified.

First, when the state of R is the state B and the sequence S1 exists, the following processing is performed.

An azimuth region defined in a clockwise direction with a satellite azimuth associated with an arbitrary term in S1 as a start azimuth and a reverse azimuth of the satellite azimuth associated with the arbitrary term in S1 as an end azimuth. If there is a satellite azimuth associated with the central term of S0, the measurement direction z is the satellite azimuth associated with the central term of S0, otherwise,
The measurement direction z is the reverse direction of the satellite azimuth associated with the central term of S0.

As the optional term of S1, the first term of S1 may be used.

When the state of R is the state B and the sequence S1 does not exist, the following processing is performed.

An azimuth defined in a clockwise direction with a satellite azimuth associated with an arbitrary term in S2 as a start azimuth and a reverse azimuth of the satellite azimuth associated with the arbitrary term in S2 as an end azimuth. If the region has a satellite azimuth associated with the central term of S0, the measurement direction z is the reverse of the satellite azimuth associated with the central term of S0; otherwise, the measurement direction z is the center of S0. The satellite azimuth itself associated with the term.

As the optional term of S2, the first term of S2 may be used.

When written in virtual code, it is as follows.

[0093]

(Equation 2)

Finally, when the state of the result R is the state C, the following is performed. The data processing unit notifies the result output unit 4 that the process is an exception process.

In the case where R is in state C, the case of (0,0,0,0) indicates that the sky is completely shielded. Encourage use in open places in the sky.

In the state C where R is (1, 0, 0, 0), the case is extremely rare. The satellite is captured only in the measurement direction or the counter measurement direction. Prompt rotation 90 degrees clockwise, resulting in (0,0,1,0) or (0,0,0,1). This is state A,
The direction can be limited.

In the state C in which R is (1,1,0,0), it is extremely rare. The satellite is captured only in the measurement direction or the counter measurement direction. Prompt rotation 90 degrees clockwise, resulting in (0,0,1,1). This is state A and the direction can be limited.

If R is in the state C and the number of the sequence is 2 or more, it cannot be geometrically possible. It is unlikely to occur. If this occurs at a certain frequency, interference from communication equipment using a strong 1.5 GHz band such as a mobile phone may be considered. For example, encourage them to change places.

In the following, the operation for explaining the operation of the result output unit 4 will be described.

When the measurement direction is limited to the azimuth (state A) or the azimuth is specified (state B), the result output unit 4 outputs the sound to the observer. In the exceptional case of state C, the individual examination is performed as described above, and the observer is urged to change the direction by 90 degrees or to use the camera in a place with more open sky. The voice output prompting the observer to change the direction by 90 degrees is performed because it has an effect of returning the state of R to the state A. In addition, if interference from other devices using the 1.5 GHz band is considered, the user is prompted to turn off the mobile phone.

Outputting by voice is because it can be used appropriately for visually impaired persons for action support, but may be displayed on a liquid crystal screen or the like.

At this time, the information to be output may include the following. The direction information of the measurement direction (direction limitation or direction specifying result), current time, latitude, longitude, altitude, last positioning time, and recommendation to the observer in the case of exception processing.

By the way, the output format of the azimuth angle of the measurement direction 5 in the azimuth limitation is, when the rotation direction is determined, the start azimuth (hereinafter referred to as α) and the end azimuth (hereinafter referred to as β).
(Α, β) can be transmitted to the observer by voice or the like, but the present invention is not limited to this, and the following output format is also possible. That is, it can also be indicated by a voice in the form of (θ, δ) as an approximate azimuth (hereinafter referred to as θ) and a one-sided error (hereinafter referred to as δ). θ and δ are given as follows.

(Equation 3) Here, x MOD y represents the remainder when x is divided by y.

(Α, β) form when the rotation direction is determined,
The two output formats, shown in and (θ, δ) format, are:
It can be immediately converted to the other format, and no matter what format you give it to, there is no particular change in its numerical meaning. Therefore, in consideration of the purpose and convenience of the user, the observer's convenience may be enhanced as an observer selection system. Alternatively, both may be output.

Further, if a certain angle is always added to the result output and the result is output, if the convenience of the observer is enhanced, it is sufficient to do so. For example, when attaching the first planar antenna 1a to the chest and the second planar antenna 1b to the back, the measurement direction
Since z is the body-side right direction, when the result is expressed as (x-90) degrees, the azimuth angle in front of the observer's body is obtained, and the convenience is improved.

In the above, the flow of processing as viewed from the apparatus side has been described. Below, in addition to the procedure from the observer's side,
The flow of a more specific information acquisition process will be described in detail.

[0107] In general, when the measurement direction is oriented in a random direction and the state of R is the above-described state A, the direction can be limited without rotation without rotation. From the direction limitation, if you want to go one step further and get higher accuracy, stop at a certain angle with a rotation with an upper limit, the state of R will be the above-mentioned state B, and go one step further than the direction limitation The direction can be specified. Alternatively, when the measurement direction is oriented in a random direction, if R accidentally obtains the state B described above, the direction can be specified immediately. These will be described based on actual examples. For convenience of explanation, first, azimuth limitation will be described, and then azimuth identification will be described.

FIG. 3 shows an example of a relationship between a satellite arrangement in the sky and two antennas when the azimuth is limited by the azimuth information acquiring apparatus according to the above-described embodiment. The concentric drawing in FIG. 3 is a view assuming that the hemisphere in the sky centered on the zenith direction of the observer's point is looked down from further above the zenith. The outer circumference circle shows an elevation angle of 0 degrees, and each concentric circle shows an elevation angle every 10 degrees. The azimuth angle is north (0 degrees)
Clockwise, east (90 degrees), south (180 degrees), and west (270 degrees) are supplementarily written. Small scattered circles represent GPS satellite positions indicated by elevation and azimuth. In this figure, 12 satellites are drawn. There are small circles painted black, small white circles, and small gray circles.
They each correspond to the following: The gray circle is
GPS satellites that have been excluded from processing for the above-mentioned rational reasons in the processing process.
GPS satellites that are later determined to be in the coverage area of the planar patch antenna 1a, and small white circles are GPS satellites that are later determined to be in the coverage area of the second planar patch antenna 1b. In the center, two planar patch antennas 1a, 1b
Are set up vertically on the ground in parallel.

The observer does not know the arrangement status of each satellite above the position where he stands. The first planar patch antenna 1a and the second planar patch antenna
Assume that 1b is installed in parallel and retrograde, vertically on the ground, in a random direction as shown at the center in FIG. The measurement direction 5 is indicated by a dotted line. The measurement direction indicated by the dotted line implies that the azimuth is not specified in this azimuth limitation. An anti-measurement direction is shown on the opposite side of the measurement direction 5 by 180 degrees. At this time, the observer does not yet know the satellite arrangement in the sky as shown in this figure.

Hereinafter, the process of limiting the measurement direction 5 to the azimuth will be specifically described. At this time, the observer only needs to stand while wearing the azimuth information acquisition device or hold the azimuth information acquisition device so as not to move, and the observer does not need to perform an action such as rotation.

On the basis of the results that the GPS receivers 2a and 2b connected to the first and second planar patch antennas 1a and 1b individually output,
Displays the data table with 12 rows and 7 columns created by the data processing unit 3.
Shown as 1.

[0112]

[Table 1]

The rows of the satellites that have been determined to be excluded are shown in the bottom two rows. These are not used for obtaining azimuth information.

The data processing unit 3 constructs a directional circular array R following the seventh column of the data table of Table 1, that is, the last item of the sequence read out from the area determination. In the data of Table 1, R is represented as “1,2,2,2,2,2,1,1,1,1 (return to the top)”.

The data processing unit 3 first checks the internal structure of R as a set of finite number sequences S0, S0 ', S1, S2, and checks the number of them. As a result, in the case where the number of the sequence is (0, 0, 1, 1), it is clear that this is the state A.

The first and last terms of the sequence S1, S2 are as follows.

(Equation 4)

[0117]

[Table 2]

The data processing unit 3 starts processing when R is in the state A. In the case of the state A, the first direction information and the second direction information can be obtained.

The first direction information that can be obtained in the case of the state A is shown. If the sequence S1 is present, the satellite azimuth associated with the end term of S1 as the start azimuth, the opposite direction of the satellite azimuth associated with the first term of the sequence S1 as the end azimuth,
An azimuth angle (z degrees) in the measurement direction exists in an azimuth angle area defined in the clockwise direction.

That is, as the first azimuth information, the starting azimuth angle
It is determined that the measurement direction (z) exists in a range defined in a clockwise direction from 6 degrees to the terminal azimuth angle (236 degrees + 180 degrees) = 56 degrees.

The second direction information that can be obtained in the case of the state A is shown. When the sequence S2 is present, the start azimuth is the reverse direction of the satellite azimuth associated with the end term of S2, and the satellite azimuth associated with the first term of the sequence S2 is the end azimuth.
An azimuth (z degrees) in the measurement direction exists in an azimuth range defined in the clockwise direction.

That is, as the second azimuth information, the starting azimuth (218 degrees + 180 degrees) = 38 degrees and the ending azimuth (244 degrees + 180 degrees)
It is determined that the measurement direction (z) exists in the range defined clockwise up to 64 degrees.

In FIG. 3, as the first direction information,
This range is indicated by an arc having a double arrow, that is, a range defined clockwise from a start azimuth angle of 6 degrees to an end azimuth angle of 56 degrees.

In FIG. 3, as the second direction information,
In the upper right direction of the outer circle, this range is defined by a circular arc having a double arrow, that is, from the starting azimuth (218 degrees + 180 degrees) = 38 degrees to the end azimuth (244 degrees + 180 degrees) = 64 degrees. To the extent indicated.

From the intersection of the two pieces of azimuth information described above, the data processing unit 3 can immediately limit the azimuth range of the measurement direction 5 (without rotation, etc.). That is, the measurement direction 5 is a start azimuth angle of 38 degrees and an end azimuth angle of 5 degrees.
The data processing unit 3 can determine that the data exists within the range defined in the clockwise direction by 6 degrees.

In FIG. 3, an azimuth range whose final output is an arc having a double-headed arrow, that is, an arc having a starting azimuth (218 + 180) = 38 degrees to an ending azimuth 56 degrees is located above and to the right of the outer peripheral circle. Shown as up to.

As described above, according to the azimuth information acquiring apparatus according to the present embodiment, the azimuth can be immediately limited without requiring rotation or the like.

The result is outputted to the observer by voice. Expressing in the form of a set (α, β) of the start azimuth and the end azimuth when the rotation direction is determined, (start 38 degrees, end 56 degrees) is output. When expressed as a set (θ, δ) of the approximate azimuth angle (θ) and the one-sided error (δ), which is another expression form that can be limited to the azimuth, (approximate value 47 degrees, one-sided error 9 degrees)
Becomes Both formats may be output.

Practical examples of these two expression formats will be described.

For example, for an application in which an azimuth angle that should never proceed from the current position is known, and it is desired to quickly confirm at least during the action that the direction in which the vehicle is going to proceed is at least not that direction, the (α, β) format The output is convenient. For example, when a visually impaired person is requested to evacuate quickly from a certain latitude and longitude after receiving a report of a nuclear accident, he / she walks by himself without waiting for the helper to arrive. I do. Waiting for the helper to arrive and spending time identifying the direction will increase the amount of exposure to serious health damage. Alternatively, when crossing an avalanche-prone area, a climbing party or the like needs to keep moving quickly and proceed while confirming that the course is not facing a certain dangerous direction. It is valid. If you think that you are going straight ahead in the snowy field, there is almost no feature to visually apply the correction feedback of the direction of travel, or if there is no visibility due to snowstorm or fog, the course control from visual information in the first place This is because it is impossible to provide feedback to the driver, and the track becomes a curved wake sooner, and the driver often steps into a dangerous area. It is very convenient to be able to restrict the azimuth in the body direction or the line of sight without instantaneous rotation, etc., even while acting in this way.

On the other hand, when it is desired to quickly find the azimuth angle value for a specific direction of interest with good coarse accuracy, the latter (θ, δ) format is more intuitive and convenient. When a specific terrain or feature (mountain, artificial structure, etc.) is visible, there are a plurality of similar ones, and it may not be possible to identify which one without the azimuth information. There is not enough time to stop and bother to identify the azimuth and identify the terrain and features on it, but as long as the approximate azimuth information of the gaze direction can be obtained, the object alone can be selected from several possible options, This is the case where it is possible to identify a specific mountain or a specific building.
Since neither of them requires rotation or the like, it is possible to take advantage of the ability to immediately limit the direction while walking.

If it is determined that R is in the state A, the measurement direction 5 is not rotated, and a fixed azimuth angle determined by the start azimuth angle, the end azimuth angle, and the rotation direction such as the clockwise direction is used. The procedure in which the measurement direction 5 is immediately derived as the range is shown in Tables 1, 2 and the example of FIG. 3 to show that two output formats are possible. Although the frequency of this state A, as described later, when installed at random,
It occurs with a probability exceeding 90%.

Now, it is assumed that the result of azimuth limitation is obtained for the measurement direction 5. When the azimuth is specified by proceeding one step further, the observer horizontally rotates the azimuth information acquisition device in, for example, a clockwise direction (a counterclockwise direction may be used, or any rotation direction).

With the rotation, the data processing unit 3 can detect the occurrence of the number 0 in the seventh column, that is, the occurrence of S0 in the internal structure of R. The data processing unit 3 notifies the observer of this fact with a special tone through the result output unit 4, and stops the horizontal rotation.

FIG. 4 shows another example of the relationship between the satellite arrangement in the sky and two antennas when the azimuth is specified by the azimuth information acquiring apparatus according to the embodiment of the present invention. The concentric drawing in FIG. 4 is a view assuming that the hemisphere in the sky centered on the zenith direction of the observer's point in a state where the rotation is stopped is looked down from above the zenith. The outer circumference circle shows an elevation angle of 0 degrees, and each concentric circle shows an elevation angle every 10 degrees. The azimuth angle is clockwise east (90 degrees with north (0 degrees) above)
Degrees), south (180 degrees), and west (270 degrees). Small scattered circles represent GPS satellite positions indicated by elevation and azimuth. In this figure, 12 satellites are drawn. There are small circles painted in black, small circles in white, small circles in gray, and small circles characterized by a cross line pattern, which correspond to the following. The gray small circles are GPS satellites that have been excluded from processing for reasonable reasons in the processing,
Small black circles are GPS satellites that are later determined to be in the coverage area of the first planar patch antenna 1a, and small white circles are later determined to be in the coverage area of the second planar patch antenna 1b. Various GPS satellites. The small circles characterized by the crossing pattern are the first planar patch antenna 1a and the second
These are GPS satellites that are later determined to be on the boundary of the coverage area of the planar patch antenna 1b, and two planar patch antennas 1a and 1b are installed parallel to the center and vertically on the ground at the center. Have been.

In the concentric circle diagram of FIG. 4, the anti-measurement direction 5 extending in the lower left direction coincides with the azimuth of the satellite 9. It is assumed that, after the orientation is limited in the state of FIG. 3, it is assumed that the clockwise horizontal rotation reaches FIG. 4. The same figure can be used to explain the case where the satellite is captured above.

Table 3 is a data table created by the data processing section 3 at this time. Rows of satellites that have been excluded are shown as the bottom two rows. These are not used in the subsequent processing.

[0138]

[Table 3]

The data processing section 3 assumes that the last term of the sequence read from the seventh column of the data table of Table 3 follows the head, and forms R, which is a sequence of circular numbers in a direction. In the data of Table 3, R is "1,2,2,2,2,2,0,1,1,1 (return to the top)".

The data processing unit 3 first checks the internal structure of R as a set of finite sequences S0, S0 ', S1, S2. as a result,
It is determined that the case is (1,0,1,1), that is, state B.

The information of the sequence is as follows.

(Equation 5)

[0142]

[Table 4]

Therefore, the data processing unit 3 starts processing when R is in the state B.

When the state of R is the state B, and
If the sequence S1 exists, the following processing is performed.

A clockwise direction is defined with the satellite azimuth associated with the first term of S1 as the starting azimuth and the opposite direction of the satellite azimuth associated with the first term of S1 as the terminal azimuth.
If the central term of S0 exists in the azimuth angle area, the measurement direction
z is the central term of S0, otherwise the measurement direction z is S0
In the opposite direction of the central term.

Since S1 exists, the following is checked first.

The satellite azimuth (A (S
(1,1) = 262) as the starting azimuth, the opposite direction (A (S1,1) + 180 = 26) of the satellite azimuth (A (S1,1) = 262) associated with the first term of S1.
2 + 180 = 82) with the terminal azimuth angle asking whether there is a central term of S0 (A (S0, m0) = 236) in the azimuth angle region. This is equivalent to asking if there are 236 degrees between 262 and 82 degrees clockwise. The answer is "not present." This question is used to identify whether the satellite at the boundary has caught in the measurement or anti-measurement direction.

Therefore, the procedure in the case where there is no data, "the measurement direction z is the opposite direction (A (S0, m0) +180) of the central term (A (S0, m0)) of S0" is adopted. Then z = A (S0, m0) + 180 = 236 + 180
= 56.

Therefore, the measurement direction is specified as 56 degrees.

As described above, after limiting the azimuth,
The direction can be specified by horizontal rotation.

This rotation has the following upper limit, and the azimuth can be specified by rotating within this range.

The following description is based on the fact that the upper limit angle of the necessary rotation is known when the state is changed from the state shown in FIG. 3 to the state shown in FIG. 4 by rotation, and the fact that the ease of use is increased. explain.

For example, when the orientation is limited as in the cases of Table 1, Table 2, and FIG. 3, twice the obtained one-sided error width angle (δ), that is, the two-sided error width angle (2δ) It is only necessary to rotate the measurement direction 5 with the upper limit. The fact that the two-sided error width angle becomes the upper limit is apparent from FIG. In FIG. 3, the measurement direction 5 is smaller than the error width on both sides (2δ).
Or you can catch one or more satellites in the anti-measurement direction. The rotation direction may be either clockwise or counterclockwise. In the case of horizontal rotation in the clockwise direction in FIG. 3, the satellite 9 is captured at a rotation angle of less than 2δ, and the state shown in FIG. 4 is obtained. When horizontally rotated in the counterclockwise direction, the satellite 14 is captured at a rotation angle of less than 2δ.

Since it is sufficient to perform only the rotation with the angle 2δ as the upper limit without rotating to an unnecessarily large angle, there are the following advantages.

(1) For the observer, it is possible to prevent excessive rotation, and it is easy to attain the target azimuth specification with a minimum necessary effort. (2) When the direction limitation result is obtained, the upper limit of the time required for specifying the direction can be estimated. Therefore, the observer can accurately judge whether or not to go one step further and specify the azimuth in light of his / her own time during outdoor activities.

As described above, according to the azimuth information acquiring apparatus according to the present embodiment, in addition to being able to limit the azimuth of the measurement direction 5 without rotation, the minimum rotation is required even when the azimuth is specified one step further. It was just good to do.

Hereinafter, the mounting configuration will be described.

When the present invention is actually used, it is configured as follows, and it is possible to enjoy the convenience due to the structure using two planar patch antennas in parallel.
FIG. 5 is a configuration example in which the azimuth information acquisition device is formed in a shape suitable for mounting. (a) is a figure which looked down at the head wearing state from the upper part. (b) is a view of the head mounted state as viewed from the left side.
(c) is a view of the head mounted state as viewed from the front, and the measurement direction in this case is a direction protruding forward from the paper surface. That is, the head of a person is sandwiched in the gap between the first planar patch antenna 1a and the second planar patch antenna 1b according to the present invention.

In the case of such a configuration example, that is, it can take a shape similar to a headband shape, a headphone shape, or a hat shape, the following advantages are obtained.

(1) Since the measurement direction 5 of the apparatus always coincides with the frontal direction of the observer's face, even when the operation of acquiring the azimuth information, the numerical value which is the result of the acquired azimuth information is used. Also, direct understanding is possible and convenience is high.

(2) Wearing on the head can maximize the vertical distance between the azimuth information acquisition device and the ground, and can minimize the influence of terrestrial and terrain shielding. It is a target.

(3) There is an example of a headwear of a decorative device such as a headband or a functional device such as a headphone, and the wearing itself can be easily received without a sense of incongruity in appearance.

(4) The rotation for identifying the azimuth may be a movement that naturally forms a distant view, and is simple and easy to accept in appearance.

The physical entity of recent GPS receivers is a microprocessor for signal processing and an associated electronic base, and is small. In fact, current portable GPS receivers
There are inexpensive ones that easily fit in the palm. From this, it can be seen that the size of the element part is considerably small. As the azimuth information acquisition apparatus that embodies the azimuth information acquisition method according to the present invention, since the components used in these portable GPS receivers can be utilized and configured, the azimuth information acquisition apparatus is also used. There is an advantage that the volume can be reduced and the size can be reduced. For example, the first GPS receiver 2a and the data processing unit 3 are housed on the back of the first planar patch antenna 1a. The second GPS receiver 2b and the result output unit 4 are housed on the back of the second planar patch antenna 1b. A flexible cable is housed inside the headband-like structure, and connection is performed to realize the configuration shown in FIG. From the result output unit 4, it is possible to output sound with a speaker or earphone.

Further, it may be attached to both outer sides of the upper limb of the clothing, that is, both outer sides of the upper limb of the jacket. So that it is perpendicular to the ground on the clothes on both outer sides of the upper arm,
It is a rule to install them so that they face each other in parallel. In addition, if they are installed so that the mutual planes are parallel to the front direction of the body, the measurement direction 5 comes to the front direction of the body. In this case, the GPS receiver may be housed behind the flat patch antenna. In this case, the portion connecting the two may be formed of a flexible cable, from the outside of the upper limb via the shoulder, behind the neck and the shoulder on the opposite side, and reach the other flat patch antenna. In order to temporarily fix this, a pressure-bonding release tape can be used. The data processing unit 3 and the result output processing unit 4 may be housed and built behind one of the planar patch antennas, or may be designed to be located on the shoulder or the back of the neck. good. Further, a flat antenna may be installed in front of and behind the body, on the chest and back, in parallel and facing backward. In this case,
When the 1st planar patch antenna 1a is placed on the back and the 2nd planar patch antenna 1b is placed on the chest, the measurement direction 5
Turns. Therefore, it is convenient for the observer that the result output unit 4 always outputs a value converted in the forward direction of the chest of the observer, that is, a value obtained by adding 90 degrees clockwise.
With such a configuration, the following advantages occur.

(1) The front of the body is made to coincide with the measurement direction, which is convenient. (2) It is easy to rotate with only a slight movement of the body. (3) There are few projections, etc., so it is easy to accept without noticeable. (4) It can be worn on clothes that the observer prefers. in this case,
If it is configured to be detachable with a pressure-bonding release tape or the like, it is convenient for washing.

[0167] It can also be worn on both outer limbs and on both outer limbs of a pair of shoes. Also in this case, the antenna and other functional parts are temporarily fixed with a pressure-bonding peeling tape or a magnet, and as a method of connecting both, the antenna and each functional part are connected by a flexible cable from the outside of the lower limb through the waist etc. If it realizes, it may become detachable. In this case, the signal capturing performance of the high-elevation angle satellite is considered to be reduced due to the shielding effect of the arm or the like. However, as described above, there is no particular problem in the present invention because a satellite existing at a particularly high elevation angle is not used. Therefore, the user does not care much about the shielding related to the high elevation angle.

The processing when R is in state C will be additionally described. In this process, it was recommended that the output to the observer be turned 90 degrees to the left or right and re-measured, or that it be used in a clearer place above the sky. A beep sound indicating these meanings may be separately determined.

Next, a computer simulation which statistically calculates how much azimuth limit value can be obtained when the azimuth information acquisition apparatus embodying the azimuth information acquisition method according to the present invention immediately limits the azimuth. The results are shown.

In this computer simulation,
35 degrees 40 minutes 14.9 seconds north latitude, 139 degrees 45 minutes 33.4 seconds east longitude, that is, the orbital information of satellites observed in the sky at multiple times on February 17, 2000 at the center of Hibiya Park in Tokyo. And try to set the measurement direction at random, and see how much azimuth limited width is obtained.

Each fixed time from 0:00 to 11:00 (0:00, 1:00,
2 o'clock, 3 o'clock, 4 o'clock, 5 o'clock, 6 o'clock, 7 o'clock, 8 o'clock, 9 o'clock, 1 o'clock
(0 o'clock, 11 o'clock). This is because at least the number of satellites having an elevation angle of 0 degree or more, that is, the number of available satellites and the satellite constellation (satellite constellation) fluctuate depending on the time, and this is reflected correctly in the evaluation.

Aiming at obtaining a result close to reality, it is assumed that an elevation angle of 5 degrees or less, which is susceptible to feature occlusion, cannot be used. The constraint described above that excludes high-elevation satellites was used.

Further, as in the case of actual use, in order to realize the randomness of the measurement direction 5, the selection of the measurement direction 5 is performed by using a random number (0
359 degrees) and random orientation was set using the occurrence.

The trial of random numbers under this condition was repeated 1000 times at each time, with the aim of improving the accuracy of the evaluation result.

As a result, a total of 12000 times (12 times × 100
(0 times), the two-sided error is 30.8 as an average value.
The result was a degree.

Twelve azimuth displays that are used in human life, such as north, northeast, northeast, east, southeast, southeast, south, southwest, southwest, west, northwest, and northwest, are azimuth displays at intervals of 30 degrees. It is. By using the method of the present invention, it is possible to limit the azimuth with such a value without rotation even in random measurement.
This indicates that the present invention has a great effect with a simple operation.

In the first installation in the random direction (without rotation), the probability that one or more satellites were accidentally captured in the plane including the measurement direction 5 and the zenith and that the direction could be immediately identified as At 9.9%, it was possible to identify the bearing at a relatively high rate.

[0178] The common coverage area is defined by adding 2.
Computer simulations are performed assuming a band width of 5 degrees.

When expressed by the probability of occurrence of a state, the state
The probability of occurrence of A is 90.1%, and the probability of occurrence of state B is 9.9%. In the former, satellites exist in both the coverage area of the first planar patch antenna 1a and the coverage area of the second planar patch antenna 1b ((0,
0,1,1) case. Similarly, the latter are all covered by the first planar patch antenna 1a and the second planar patch antenna 1b
In both cases, satellites existed in both areas (case (1,0,1,1)). While in state A, the first planar patch antenna
Satellites are unevenly distributed only in the coverage area of 1a (corresponding to the case of (0,0,0,1)), or satellites are unevenly distributed only in the coverage area of the second planar patch antenna 1b ((0,0,1 , 0)), the situation is:
It did not appear even after 12,000 total trials. Despite state B, the uneven distribution situation ((1,0,0,1), (1,0,1,0), (1,1,0,
1), (1,1,1,0)) did not appear.

The above description has been made only with respect to the functions of limiting the direction and specifying the direction in the direction information acquiring apparatus according to the present embodiment. However, as is clear from the configuration of FIG. 2, the equipment necessary for positioning is provided. Therefore, the azimuth information acquisition device according to the present embodiment can also realize positioning. In mid-latitude regions, there are always about 8 to 12 GPS satellites in the sky. Therefore, it is usually 4 on one side divided by the majority circle passing through the zenith
One to six satellites can be expected. In principle, two-dimensional positioning is possible with at least three satellites and three-dimensional positioning is possible with at least four satellites, indicating that sufficient positioning can be achieved with half of the hemisphere in the sky. The positioning result may use the positioning result sent from the first GPS receiver 2a and the second GPS receiver 2b to the data processing unit 3 as it is, for example, both the first GPS receiver 2a and the second GPS receiver 2b. Among the positioning results, the one with the latest positioning calculation time is given priority, and the result output unit 4
Output from.

As described above, the present invention has been described with reference to the drawings. However, the present invention is not limited to the above-described embodiment, but can be implemented in any manner without changing the configuration described in the claims.

[0182]

As described above, according to the azimuth information acquiring method and apparatus according to the first and sixth aspects, a pair of GPS antennas having a hemispherical antenna pattern are vertically arranged facing each other. By receiving signals from GPS satellites for each planar patch antenna, it is possible to limit the azimuth quickly without requiring rotation etc. In other words, narrow the azimuth value to a range of azimuth values in a fan shape be able to.

Furthermore, by using a low-cost L1 wave GPS receiver whose small size is widely used and making small modifications, an azimuth information acquisition device capable of realizing an azimuth information acquisition method can be realized in a realistic manner. Can be manufactured at cost.

In addition, in the implementation, the flat patch antenna is excellent in mountability on both sides of the head due to the small size and light weight of the flat patch antenna and its parallel installation characteristics. High convenience can be provided to the observer by matching the direction.

According to the azimuth information acquiring method and apparatus according to the second and seventh aspects, the azimuth can be further specified by horizontal rotation having a clear upper limit based on the azimuth width range obtained by azimuth limitation. Can be easily performed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram showing the principle of azimuth information acquisition of an azimuth information acquisition method according to the present invention.

FIG. 2 is a schematic configuration diagram illustrating an embodiment of an azimuth information acquisition device that embodies an azimuth information acquisition method according to the present invention.

FIG. 3 is a schematic layout diagram showing a relationship between a satellite in the sky and two antennas when the azimuth is limited by the azimuth information acquisition device.

FIG. 4 is a schematic layout diagram showing a relationship between a satellite in the sky and two antennas when a direction is specified by a direction information acquisition device.

5A and 5B are external views of an azimuth information acquisition device having a head mounted structure, wherein FIG. 5A is a view of the head mounted state as viewed from above, FIG. 5B is a view of the head mounted state as viewed from the left side, (c) is the figure which looked at the head mounted state from the front.

[Explanation of symbols]

1a 1st planar patch antenna 1b 2nd planar patch antenna 2a 1st GPS receiver 2b 2nd GPS receiver 3 data processing unit 4 result output unit 5 measurement direction 6a sky coverage by 1st planar patch antenna 6b 2nd planar patch antenna Overlying area 7 Most circles that define the boundary between the area covered by the first planar patch antenna and the area covered by the second planar patch antenna

Claims (7)

[Claims] 1. A pair of GPS antennas each having a hemispherical antenna pattern are vertically arranged on the ground in a direction opposite to each other, and with one major circle passing through the zenith as a boundary, the GPS antennas are positioned in the sky in the direction in which they face. Form a sky coverage area where the sensitivity of the antenna can reach each quarter sphere, and have the GPS receivers connected to each antenna attempt to capture signals transmitted from all GPS satellites in the sky half sky. From the comparison of the reception status of each GPS satellite signal in both GPS receivers, the area where one or more GPS satellites exist is determined, and the azimuth of the GPS satellite is extracted from at least one of the GPS receivers. Create a series of azimuth angles clockwise,
Azimuth information acquisition, wherein the azimuth of the first term and the azimuth of the last term are extracted, and the azimuth is limited by the azimuth of the first term and the azimuth of the last term obtained in at least one extracted area. Method. 2. A pair of GPS antennas, each having a hemispherical antenna pattern, are vertically arranged on the ground in a direction opposite to each other, and the GPS antenna is positioned above the direction in which the GPS antenna is facing, with one major circle passing through the zenith as a boundary. The sensitivity of the antenna and the sky coverage are formed in the quarter sphere, respectively, and the GPS receiver connected to each antenna tries to acquire signals transmitted from all GPS satellites in the sky half sky. From the comparison of each GPS satellite signal of both GPS receivers, the area where one or more GPS satellites exist is determined, and the azimuth of the GPS satellite is extracted from at least one of the GPS receivers. Is created clockwise, the azimuth of the first term and the azimuth of the last term are extracted, and the azimuth is limited by the azimuth of the first term and the azimuth of the last term obtained in at least one extracted area. The orientation obtained above The angle width of the angle is the upper limit of the rotation angle,
The above pair of GPS antennas are rotated horizontally, and the GPS receivers connected to the respective GPS antennas are attempted to capture signals transmitted from all GPS satellites in the hemisphere above. When it is determined from the signal that at least one satellite is present at the boundary, the horizontal rotation of the pair of GPS antennas is stopped in that direction, at least one GPS satellite is located, and at least one of the GPS satellites is determined. The azimuth of the above satellite is extracted from the GPS receiver, and the azimuth of the extracted one satellite, the azimuth in the opposite direction, and the azimuth of the satellite determined to be present at the boundary are compared to determine the azimuth. An azimuth information acquisition method characterized by identifying. 3. A method according to claim 1, wherein said pair of GPS antennas is a planar patch antenna. 4. The azimuth information acquiring method according to claim 1, wherein said pair of GPS antennas are attached to each other with their heads interposed therebetween, facing backward and parallel to each other and perpendicular to the ground. 5. The azimuth information acquiring method according to claim 1, wherein said pair of GPS antennas are mounted to face each other and parallel to each other and vertically to the ground while being sandwiched by a body. 6. A GPS antenna having a pair of hemispherical antenna patterns arranged parallel to each other, facing each other, and vertically, and each of the GPS antennas has an antenna in a quarter celestial sphere in the sky in the facing direction. A means for forming an overlying area where sensitivity is reached, and a means for capturing signals transmitted from satellites existing in the overlying area by the pair of antennas, and creating a series of satellite azimuth angles clockwise in each of the areas. Means for extracting the azimuth angle of the first term and the azimuth angle of the last term, means for determining the area where the satellite was present from a comparison of the signals from the captured satellites, and at least one of the above areas. Means for limiting the azimuth by the azimuth of the first term and the azimuth of the last term obtained in the area. 7. A GPS antenna having a pair of hemispherical antenna patterns arranged parallel to each other, facing backward, and vertically, and each of the GPS antennas has an antenna sensitivity of one quarter celestial sphere above the facing direction. Means for forming an overlying area covered by the satellite, means for capturing signals transmitted from the satellites existing in the respective overlying areas by the pair of antennas, and comparing the signals from the captured satellites to determine the presence of the satellite. Means for determining the existence area that had been, a series of satellite azimuth angles in each of the above areas in a clockwise direction, means for extracting the azimuth angle of the first term and the azimuth of the last term, Means for limiting the azimuth by the azimuth of the first term and the azimuth of the last term obtained in one region, and horizontally rotating the pair of antennas with the angle width of the obtained azimuth being the upper limit of the rotation angle Means and each time An attempt is made to capture signals transmitted from all GPS satellites in the hemisphere above the pair of rotating antennas, and it is determined from the obtained signals of each GPS satellite that at least one satellite exists at the boundary. Was
Means for stopping horizontal rotation of the pair of antennas in that direction, means for determining the presence area of at least one other GPS satellite, and means for taking out the azimuth of the satellite; azimuth of the taken out satellite; An azimuth information acquiring apparatus, comprising: means for specifying an azimuth by comparing an azimuth in a reverse direction with an azimuth of the satellite determined to be present at the boundary.