JP2002107395A - Measuring device for electric field strength - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric field strength measuring device, capable of accurately measuring the field intensity off transmission data from a satellite and moreover producing measured data easy for statistical processing. SOLUTION: Transmission data from a satellite is received with a tracking antenna, of which the direction of the antenna is controlled automatically, so as to maximize the signal level of reception signal, and the intensity data is set (S210 to S240) to E=1, if the signal level is larger than a reference level and to set E=0, if the level is equal to or less than the reference level. If the intensity data have changed from the data set at the previous activation of the processing, the device transmits commands (S250 and S260) for changing the indication method of a running track and to a navigation controller for indication-processing the present position and the running track of the measured vehicle on a map. Then GPS data, including the present position and its attributes of the position of the measured vehicle, are read (S270) from the navigation controller, and the device stores (S280), in turn, the measured data produced by correlating them with the field strength data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric field intensity measuring device for measuring the electric field intensity of a radio wave transmitted from a satellite.

[0002]

2. Description of the Related Art Conventionally, when a mobile radio communication system such as a PHS or a mobile phone is introduced in a certain area, the location of a base station for covering the area and the transmission output of radio waves are determined. It is necessary to design a line in order to install a relay station according to the requirements.

At this time, a radio wave transmitting point is set in advance, a test radio wave is transmitted, and a vehicle equipped with an electric field strength measuring device for receiving the test radio wave and measuring the electric field strength is driven to travel in various places. Intensity data indicating the electric field intensity of a received radio wave at a point and measurement position data indicating the coordinates of the measurement position are collected, and an unreceivable area is specified based on the intensity data and the measurement position data.

For example, as disclosed in Japanese Patent Application Laid-Open No. 7-253446, a map display near a point specified from the measured position data based on the intensity data and the measured position data measured as described above is used. There is also known an apparatus in which the distribution of electric field strength is displayed on a map by synthesizing data and intensity data so that the tendency of the electric field strength can be visually grasped.

[0005]

However, in recent years,
Systems for communicating and broadcasting to mobiles via satellites are being studied, and even in systems using such satellites, similar to the above-described mobile radio communication system using base stations, when starting services, etc. It is necessary to measure the electric field strength.

However, in a system using satellites, radio waves in a microwave band having a high linearity are used, and the electric field intensity of the radio waves to be received is very weak. Even when measurement is performed using the omnidirectional antenna used, stable reception cannot be ensured, and there has been a problem that accurate data cannot be obtained.

Also, the measurement data of the above-mentioned conventional device is
Since the intensity data and the measurement position data or the map display data are associated with each other, for example, it is limited to obtain a coverage ratio of a communication area on a prefectural unit, a municipal unit, or a specific road. When performing various statistical processes on an area, the dedicated conversion data that associates the coordinates represented by the measured position data with the addresses and roads is separately prepared, and the coordinates of the measured position data are calculated based on the converted data. Therefore, there is a problem that the operation for extracting the measurement data belonging to the processing target area is required, and the operation is troublesome.

The present invention has been made in order to solve the above problems.
It is an object of the present invention to provide an electric field intensity measuring device that can accurately measure the electric field intensity of a radio wave transmitted from a satellite and generates measurement data that can be easily processed in statistical processing.

[0009]

In the electric field intensity measuring apparatus according to the first aspect of the present invention, the tracking antenna tracks a satellite and receives a transmission radio wave from the satellite. Based on the reception level at the tracking antenna,
The intensity data creation means creates intensity data representing the electric field strength, and the position detection means measures the reception position of the transmitted radio wave that changes with the movement of the vehicle.

The data storage unit associates the intensity data from the intensity data creation unit with the reception position data from the position detection unit, and the attribute data extracted from the attribute storage unit based on the reception position data. The measured data is created and the measured data is stored. That is, as the vehicle travels, measurement data for each point that has passed is sequentially accumulated.

As described above, according to the electric field strength measuring apparatus of the present invention, since the tracking antenna is used, even if the transmitted radio wave from the satellite is weak or has a strong straightness, stable reception is possible. And a highly accurate measurement result can be obtained. As a result, it is possible to accurately grasp an area (particularly a road on which a vehicle can travel) in which a transmission radio wave from a satellite can be received.

Further, since the measurement data generated by the electric field strength measuring apparatus of the present invention includes attribute data representing the attribute of the point specified by the measurement position data,
Without using separately prepared conversion data or the like as in a conventional device, classification and statistical processing of measured data can be easily performed based on this attribute data.

The attribute data stored in the attribute storage means may include, for example, at least a code corresponding to an address division as described in claim 2.
As described, if at least the code corresponding to the road type is included, the transmission radio wave from the satellite is received for each specified address division (prefectural, municipal, etc.) and for each specified road type. It is possible to grasp the actual situation such as the extent of possible areas (or unreceivable areas).

Next, in the electric field strength measuring device according to the present invention, based on the reception position data from the position detection means, the map display means displays a map near the point specified by the reception position data and a vehicle running. Display the trajectory on the screen. Then, the display changing means changes the display method of the traveling locus according to the intensity data generated by the intensity data generating means.

Therefore, according to the electric field intensity measuring apparatus of the present invention, the road or the area where the measurement is not performed can be visually confirmed from the running locus of the vehicle shown on the map, and the measurement can be performed without waste and without omission. The work can be performed, and the difference in the electric field intensity at each passing point and the electric field intensity distribution can be visually confirmed from the change in the display method of the traveling locus.

As a method of displaying the traveling locus, for example, it is conceivable to change the color, shape, size, etc. according to the intensity data. Further, as the intensity data created by the intensity data creating means, the reception level at the tracking antenna may be quantified and used as it is. For example, as set forth in claim 5, the reception level at the tracking antenna is set in advance. The binarized data obtained by comparing the reference level with the set reference level may be used.

If the minimum required reception level is set to the reference level, it is possible to confirm whether or not the area is a receivable area only by referring to the intensity data. Moreover, in this case, since the intensity data can be represented by one bit,
Compared with the case where the reception level is directly digitized, the storage capacity for storing the intensity data (and thus the measurement data) can be significantly reduced. By setting a plurality of reference levels, the intensity data may be represented by three or more values.

The position detecting means may be, for example,
As described above, a GPS receiver that receives a transmission radio wave from a GPS satellite and generates reception position data including latitude and longitude can be suitably used. However, the present invention is not limited to this, and one using autonomous navigation or a combination of autonomous navigation and GPS may be used.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram illustrating the entire configuration of the electric field strength measuring device according to the embodiment. The electric field intensity measuring device of the present embodiment is mounted on a measuring vehicle called a so-called probe car, and measures the electric field intensity of a transmission radio wave from a satellite launched for communication or broadcasting. .

As shown in FIG. 1, an electric field intensity measuring apparatus according to the present embodiment includes an electric field intensity measuring section 10 for measuring the electric field intensity of a radio wave transmitted from an artificial satellite for communication or broadcasting, and a current position of a measuring vehicle. It comprises a position detection unit 20 for measurement, and a data generation unit 30 for generating and storing measurement data in which the measurement results of the electric field intensity measurement unit 10 and the position detection unit 20 are associated.

The electric field strength measuring section 10 detects a main antenna 11 for receiving a radio wave transmitted from an artificial satellite and a signal received from the main antenna 11, and converts the signal level into an analog-digital (A / D) signal. It comprises a receiver 12 for conversion and an automatic tracking device 13 for tracking an artificial satellite by controlling the direction of the main antenna 11 so that the signal level of the received signal is maximized, and corresponds to a tracking antenna of the present invention. .

The position detecting section 20 is composed of an existing car navigation system. The position detecting section 20 receives a radio wave transmitted from a GPS artificial satellite, and receives a signal from the GPS antenna 21 based on a signal received from the GPS antenna 21. GPS receiver 2 as position detecting means for calculating position data (absolute coordinates of latitude / longitude) indicating the current position, traveling data (speed, direction) indicating the moving speed and traveling direction of the measured vehicle, and the like.
2 and a display unit 23 composed of a liquid crystal display, a CRT, etc.
And a touch panel for inputting data and various commands,
An operation unit 24 including a mouse, a keyboard, and the like, and a storage medium 26 including a magnetic disk, a magneto-optical disk, an optical disk, an IC card, and the like can be mounted thereon, and a drive device 2 for reading various data from the mounted storage medium 26.
5 and a well-known microcomputer (hereinafter, referred to as a “microcomputer”) including a CPU, a ROM, a RAM, and the like, and a GPS receiver according to a control program previously stored in the ROM and various operations input from the operation unit 24. 22
It processes position data and travel data input from the storage device and various data read from the storage medium 26 via the drive device 25, and displays a map, a current position, a travel locus, and the like on the display unit 23.
And a navigation control unit 27 for executing a navigation process such as display on the navigation device.

In the storage medium 26, map data necessary for creating a map to be displayed on the screen of the display unit 23, and for each point (node) on the map, an attribute of the point, for example, Attribute data representing the address classification such as prefectures and municipalities, road types, etc. (here, the prefecture classification code,
(A municipal division code and a road type code) are stored in advance. This storage medium 26 corresponds to the attribute storage means of the present invention.

On the other hand, the data generation unit 30 is formed of an existing personal computer, and transmits and receives data between the display unit 33, the operation unit 34, the drive unit 35 similar to that of the position detection unit 20, and other devices. And a main control unit 37 composed of a known microcomputer.

In the data generator 30, the drive unit 35 is configured to be able to write data as well as read data from the storage medium 36. In addition, the main control unit 37 controls the receiver 12 of the electric field strength measurement unit 10.
And read the intensity data obtained by A / D conversion of the reception level, and instruct the navigation control unit 27 to read the position data and the traveling data, change the display method of the traveling locus, and the like. ing.

Here, the contents of the navigation processing executed by the navigation control section 27 and the data creation processing executed by the main control section 37 will be described with reference to the flowcharts shown in FIGS. Note that the data creation process is started repeatedly when the user of the electric field strength measuring apparatus operates the operation unit 34 of the data generation unit 30 to input an electric field intensity measurement command. Is
The user operates the operation unit 24 of the position detection unit 20,
When a navigation start command is input or a start command is input from the main control unit 37 to which the above-described electric field intensity measurement command is input, the operation is repeatedly started at a constant cycle.

When the navigation process is started, as shown in FIG. 2, first, in S110 (S indicates a step), position data and travel data are read from the GPS receiver 22, and then in S120. Then, the attribute data of the point specified by the position data is read from the storage medium 26.

Next, in S130, the position data and travel data read in S110 are associated with the attribute data read in S120, and stored in the RAM constituting the navigation control unit 27 as GPS data. Note that this GPS
The data is set so that it can be transmitted when a read command is input from the main control unit 37.

At S140, it is determined whether or not a trajectory display change command for changing the display method of the trajectory has been input from the main controller 37. If the command has not been input, the process directly proceeds to S160. If the command has been input, the process proceeds to S150, in which the setting for changing the display method of the travel locus (for example, the color, shape, and size of the mark for displaying the travel locus) is performed in accordance with the locus display change command, and then the process proceeds to S16.
Go to 0.

In step S160, based on the position data read in step S110, data for displaying a map near a point specified by the position data is read from the storage medium 26, and a map generated based on the data is displayed on the display unit. The current position of the vehicle and the vehicle every time the vehicle moves by a predetermined distance are displayed on the screen 23 and based on the traveling data read in S110 and the display method of the traveling locus set and changed in S160. A map for displaying the travel locus on the map on the screen of the display unit 23 and a travel locus display process are executed, and the process ends. It should be noted that the map and traveling locus display processing is well known in the navigation device, and therefore, a more detailed description is omitted here.

In other words, the position detecting section 20 comprising the existing car navigation system is provided with a process for displaying the current position and the running locus of the measured vehicle together with the map on the display screen of the display unit 23 in addition to the original processing. Thus, a process for supplying GPS data in response to a request from the outside or changing a display method of a traveling locus is executed.

As a result, on the display map of the display unit 23,
Every time the measurement vehicle travels a predetermined distance, a mark of a traveling locus corresponding to the intensity data is sequentially displayed on the traveling road, and eventually, the distribution of the electric field intensity is displayed on the road on which the measurement vehicle traveled. . Next, a data creation process executed by the main control unit 37 will be described.

When this process is started, as shown in FIG. 3, first, in S210, the receiver 1 of the electric field strength measurement unit 10
The signal level converted from 2 to a digital value is read. At S220, the read signal level is lower than a preset reference level (for example, the lowest level at which radio waves from artificial satellites can be received normally). It is determined whether it is large. If the signal level is higher than the reference level, the process goes to S230 to set the intensity data to 1 (E = 1), while if the signal level is lower than the reference level, the intensity data is set to 0 (E = 0).

In S250, the process is compared with the intensity data at the time of the previous activation to determine whether or not the value has changed. If the value has not changed, the process directly proceeds to S270.
On the other hand, if it has changed, the process proceeds to S260, and after outputting a locus display change command to the navigation control unit 27, the process proceeds to S270.
Proceed to.

In step S270, a read command is output to the navigation control unit 27 so that the navigation control unit 27
The S data is read, and in S280, the GPS data is read.
The data associated with the intensity data set in S230 or S240 is stored as measurement data in the storage medium 36, and the process ends.

By repeatedly executing this process, as shown in FIG. 4, position data P1, P2, P3... Comprising absolute coordinates (X, Y) of latitude and longitude representing the reception position are obtained.
The traveling data at that time (vehicle speeds V1, V2, V3... And traveling directions D1, D2, D3...) And attribute data (prefecture classification codes A1, A2, A
3, municipal classification codes B1, B2, B3, road type codes C1, C2, C3, altitudes H1, H2, H3
..) And intensity data E1, E2, E3,... Generated based on the electric field intensity at the receiving position.

In this embodiment, S210 to S2
40 is intensity data generation means, S210, S270, S2
80 is data storage means, S170 is map display means, S1
40, S150, S250, and S260 correspond to a display change unit. As described above, the electric field strength measuring apparatus of the present embodiment uses a so-called tracking antenna, which automatically controls the direction of the antenna so that the signal level of the received signal of the transmitted radio wave from the artificial satellite is maximized. Since it is configured to receive, it is possible to reliably receive a transmission radio wave from an artificial satellite that is weak and strong in straightness, and obtain a highly accurate measurement result.

Further, in the electric field intensity measuring device of this embodiment,
Intensity data based on the measurement result of the electric field strength, as well as position data indicating the measurement position, traveling data at the time of measurement, and attribute data of the measurement position are sequentially stored in the storage medium 36 as measurement data. It has been like that.

Therefore, by using the measurement data stored in the storage medium 36, it is possible to easily extract the measurement data relating to the specified specific area or the specific road based on the attribute data. Statistical processing such as calculating the ratio of the area in which radio waves from satellites can be received can be easily performed without requiring separately prepared map data or the like.

In the present embodiment, the display method of the traveling locus of the measurement vehicle displayed on the display unit 23 of the position detection unit 20 changes according to the intensity data. Can be visually checked with the roads where the measurement has not been performed, so not only can duplicate measurement be prevented and the measurement can be performed efficiently, but also the distribution of the electric field strength (strength data) as the measurement result can be visually checked. be able to.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.
Various embodiments can be adopted. For example, in the above embodiment, measurement data is stored in the storage medium 36 and data is supplied to an external data processing device via the storage medium 36. A wireless telephone (mobile phone, PHS
), And stores the measurement data in a memory constituting the main control unit 37. Each time the measurement data is accumulated to some extent, the measurement data is transmitted to an external data processing device via a wireless telephone, An external data processing device may be directly connected to the port 38 to supply the stored measurement data to the outside via the communication port 38.

In the above-described embodiment, the intensity data obtained by expressing the signal level in a binary order is used to represent the electric field intensity. However, the signal level read from the receiver 12 may be directly used as the intensity data. Alternatively, intensity data representing signal levels in three or more stages may be used.

Further, in the above embodiment, the main control unit 37
Although the control program for executing the data creation processing has been described as being stored in advance, the control program may be read via the drive device 35 and executed. Further, in the above embodiment, the position detection unit 20 and the data generation unit 30 are configured separately,
As shown in FIG. 5, the main control unit 37 of the data generation unit 30
The GPS receiver 22 is directly connected to the storage medium 2
6 may be integrated by reading the data stored in 6 via the drive device 35 and causing the main control unit 37 to execute the navigation process.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an entire configuration of an electric field strength measuring device according to an embodiment.

FIG. 2 is a flowchart illustrating the contents of a navigation process executed by a navigation control unit.

FIG. 3 is a flowchart illustrating the contents of a data creation process executed by a main control unit.

FIG. 4 is an explanatory diagram showing the contents of measurement data created as a result of the data creation processing.

FIG. 5 is a block diagram illustrating another configuration example of the electric field strength measuring device.

[Explanation of symbols]

10 electric field strength measurement section 11 main antenna 12
... Receiver 13 ... Automatic tracking device 20 ... Position detector 21
... GPS antenna 22 ... GPS receiver 23,33 ... display unit 2
4, 34 operation unit 25, 35 drive device 26, 36 storage medium
27 navigation controller 30 data generator 37 main controller 38
… Communication port

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) H04B 17/00 H04B 7/26 K F term (reference) 2F029 AA02 AB07 AC02 AC08 AC14 5H180 AA01 BB12 BB13 CC12 FF05 FF22 FF33 5J062 AA05 BB01 CC07 HH04 5K042 AA05 AA06 CA02 CA12 CA17 CA23 DA19 EA15 FA11 GA02 GA11 HA02 JA05 5K067 DD44 EE02 EE07 GG11 KK02 LL11

Claims (6)

[Claims] 1. An electric field strength measuring device mounted on a vehicle for sequentially measuring the electric field intensity of a transmission radio wave from a satellite as the vehicle travels, wherein the reception position of the transmission radio wave that changes with the movement of the vehicle is determined. Position detecting means for measuring; attribute storing means for storing attribute data representing attributes at each point in a region where electric field strength is to be measured; tracking for tracking the satellite and receiving a transmission radio wave from the satellite; An antenna, intensity data creating means for creating intensity data representing electric field intensity based on a reception level at the tracking antenna, intensity data from the intensity data creating means, receiving position data from the position detecting means, Data storage means for creating measurement data in association with the attribute data extracted from the storage means based on the reception position data, and accumulating the measurement data. Characteristic electric field strength measurement device. 2. The electric field strength measuring apparatus according to claim 1, wherein the attribute data stored in the attribute storage means includes at least a code corresponding to an address division. 3. The electric field intensity measuring apparatus according to claim 1, wherein the attribute data stored in the attribute storage means includes at least a code corresponding to a road type. 4. A map display means for displaying, on a screen, a map around a point specified by the received position data and a traveling locus of the vehicle based on the received position data from the position detecting means, The electric field intensity measuring device according to any one of claims 1 to 3, further comprising: a display changing unit that changes a display method of the traveling locus according to the intensity data from the data creating unit. 5. The apparatus according to claim 1, wherein said intensity data generating means sets binarized data obtained by comparing a reception level at said tracking antenna with a predetermined reference level as said intensity data. The electric field intensity measuring device according to claim 1. 6. The GPS receiver according to claim 1, wherein the position detecting means is a GPS receiver that receives a transmission radio wave from a GPS satellite and generates reception position data including latitude and longitude. The electric field intensity measuring device according to any one of claims 1 to 3.