JP3176981B2 - Measuring method of transmitting antenna radiation characteristics using GPS - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for measuring transmission antenna radiation characteristics.

[0002]

2. Description of the Related Art Conventionally, transmission antenna radiation characteristics (directional characteristics and gain) are measured by mounting an antenna on a large-sized dedicated rotating truck during inspection and adjustment at the time of factory shipment, and radiating radio waves from the antenna while rotating the truck. Use a field strength measuring device to measure and adjust its radiation characteristics, or if the measurement space is relatively large, fix the antenna, move around with the measuring device, measure the desired characteristics, I was adjusting. Of course, in the former case, the number of measurement points can be greatly reduced because the antenna itself rotates.

On the other hand, there are various restrictions in field (ground) electrical measurement such as when factory data is reproduced after installation on the site or when deterioration data is measured after aging. In other words, there are restrictions such as the rotation of the transmitting antenna itself is not possible, shielding of radio waves by surrounding buildings, reflection in general, and errors due to surface reflection are mixed. In many cases, measurement was not possible, and there were many problems in terms of errors, time, and labor.

[0004]

As described in the section of the prior art, once the transmitting antenna is installed on the site, the measurement of the radiation characteristics thereafter requires various errors, time, and labor. There was a problem. Therefore, an object of the present invention is to solve the above-mentioned problems, to cover a wide area in the immediate vicinity of or near the antenna at the installation site, and to reduce errors due to reflection and shielding of buildings and the ground surface, in a short time, at low cost, and safely. It is an object of the present invention to provide a method of measuring a transmission antenna radiation characteristic using GPS which enables three-dimensional measurement with guaranteed characteristics.

[0005]

In order to achieve this object, a measuring method according to the present invention provides a method for measuring the radiation characteristics of a transmitting antenna in an operating state, at least three-dimensionally near or near the transmitting antenna to be measured. The aircraft orbits an automatically or remotely controllable flying vehicle equipped with a device for measuring position information and electromagnetic field strength, and the three-dimensional position information of the flying vehicle is based on a flying vehicle capable of receiving radio waves from at least three GPS satellites. The electromagnetic field intensity measured by the onboard satellite radio receiver and radiated from the transmission antenna under test at the position of the flying object is measured by the electromagnetic field intensity measurement device mounted on the aircraft and the transmission antenna under measurement. A series of the measured three-dimensional position information and the measured electromagnetic field strength are temporarily stored in a memory, and a predetermined number of pairs of the three-dimensional position information are measured by the receiving antenna whose direction is adjusted. And outputting the data stored in the memory after the measurement of the electromagnetic field intensity, and processing the calculated data to calculate the radiation characteristic of the transmitting antenna (for example, three-dimensionally represented). .

[0006]

According to the measuring method of the present invention, G with extremely high accuracy
Receives radio waves from the PS (Global Positioning System) satellite, absolutely measures the three-dimensional position of the electromagnetic field strength measurement point, and moves the electromagnetic field strength of the radio wave radiated from the transmission antenna to be measured through the air. In this case, the measurement can be performed automatically by receiving the data by the remotely controlled flying object, and it is possible to perform the measurement in a short time with little error over a wide range in the vicinity of the transmission antenna to be measured.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Recently, attention has been paid to a system called GPS, which uses radio waves from artificial satellites to determine its own position. This principle is based on receiving distances from three artificial satellites whose precise orbits are known in advance. It is a system that calculates by radio waves and detects its own position. One of the features of this satellite is equipped with an extremely accurate atomic clock. One of the features of the present invention is that radio waves from this satellite are used for calculating the three-dimensional position of the electromagnetic field strength measurement point. Exist.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an explanatory view for schematically understanding the measuring method of the present invention, and FIG. 2 is a configuration diagram of an embodiment of a device mounted on a mobile flying object to achieve the object of the present invention. In FIG. 1, numerals 1, 2, and 3 respectively indicate a transmitting antenna to be measured for which radiation characteristics are to be obtained, a flying object whose flight is controlled by a radio control 3 for measuring electromagnetic field strength, and a flight of the flying object. Radio control. The vehicle 2 may be an unmanned radio controlled pilot, for example a helicopter or a balloon. In the case where the flying object is an unmanned mooring balloon, the mooring can be manually operated from below to move around the transmitting antenna. In the example of the device configuration shown in FIG. 2 mounted on this flying object, the GPS satellite radio wave receiver 24 first receives radio waves from at least three GPS satellites and calculates the three-dimensional position of the flying object 2. Import as data of Since GPS satellites have extremely high precision atomic clocks, they have comparable high precision clocks on the ground, and if it is not necessary to calibrate this ground clock with the satellite clock, 3 The three-dimensional position of the flying object 2 can be determined with high accuracy only by receiving the radio waves from two GPS satellites, but if not, it is necessary to receive the radio waves from another GPS satellite to calibrate the clock on the ground There is.

[0009] Even though this global positioning system has high accuracy, as long as data from satellites that can be used at normal times are used, there is a measurement error of about 30 to 100 US on the earth. In order to cancel the error, the same receiver as the GPS satellite radio receiver 24 mounted on the flying object is also provided on the ground near the transmission antenna to be measured, and the position information of the specific point on the ground measured here is used for that purpose. It is effective to use. The electromagnetic field strength of the radiated radio wave of the transmitting antenna 1 at that position of the flying object achieves its purpose by taking the radio wave received from the receiving antenna 21 into the electromagnetic field strength measuring device 23,
At this time, it is necessary that the receiving antenna 21 is correctly oriented toward the transmitting antenna, and a compass on which the flying object is mounted is used for this control. Control including 21 postures. When the stability of the orientation, including the attitude of the receiving antenna, is not enough, the receiving antenna 21 is rotated at a fixed cycle in the plane of polarization of the received radio wave, and the measurement data is separated from the measurement data. Instantaneous data may be estimated. Radio control receiver
25 controls the movement of the flying object 2 by receiving radio control radio waves from the ground. At this time, the data and the compass 26 are sent to the control device 29 via the information processing device 28, and the position and the attitude of the flying object 2 are controlled. Control. At this time, a predetermined flight course is recorded in the flight plan 27, and the flying object can be automatically controlled based on the recorded course. Note that, for the orbiting flight course, for example, when measuring the intensity of the radiated electromagnetic field for obtaining the directional characteristics, it is usually desirable that the position and the course maintain a constant distance of three wavelengths or more. Since the final directional characteristics are calculated by the later calculation / correction method, it is not necessary to keep the characteristics constant.

Next, the three-dimensional position data and the electromagnetic field intensity data measured by the receiver 24 and the measuring device 23 are temporarily recorded in a temporary memory mounted on the flying object. These data are emitted, and a horizontal directional characteristic, FIG. 3B, a vertical directional characteristic, and the like are obtained by an arithmetic unit or the like using a predetermined calculation method and correction method. If necessary, an image information processing apparatus may be used to combine the horizontal and vertical characteristics to obtain a directional characteristic diagram by a three-dimensional representation. At this time, the temporary memory may be placed in the flying object, or may be installed on the ground, and data may be transmitted from the flying object to the ground by radio waves.
The arithmetic unit and the like may be placed on the flying object, but may be placed on the ground together with the memory for the purpose of reducing the weight of the flying object. If the flying object is an unmanned mooring balloon, the mooring line used at this time may be used to fetch position information and electromagnetic field strength data into the ground system, and then execute the subsequent memory and arithmetic processing on the ground system. Also, taking advantage of the fact that the measurement point of the electromagnetic field strength, which is one of the features of the measurement method of the present invention, is in the air, the lower part of the receiving antenna 21 is shielded with a radio wave absorber to absorb the reflection of radio waves from the ground surface. As a result, measurement errors can be reduced. Alternatively, in the calculation method and the correction method, the directivity can be easily obtained by a simple calculation that ignores the reflected wave from the ground surface.

[0011]

As described above in detail, according to the measuring method of the present invention, the radiation characteristics of an existing transmitting antenna can be implemented in an operational state with advantages not found in the conventional method in terms of error, time and labor. can do. More specifically, a three-dimensional antenna with a wide range of antennas close to the transmitting antenna installation site, with little errors due to reflection and occlusion of the building and the ground, and in a short time, at low cost, and whose safety is guaranteed. A simple measuring method can be provided. As a result, it becomes extremely easy to perform various data measurements in the technical maintenance work that enables detailed diagnosis of factory data at the installation site of transmission antenna radiation characteristics at the installation site and detailed diagnosis of antenna deterioration and failure after aging operation, etc. The effects of the final inspection on the new construction of the antenna and the periodic inspection after the installation or the characteristic confirmation inspection after the rehabilitation work are enormous.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the outline of a measurement method of the present invention.

FIG. 2 is a configuration diagram of an embodiment of a device mounted on a flying object to achieve the object of the present invention.

FIG. 3 shows examples of directional characteristics measured and calculated. (a) is the horizontal directivity of the transmitting antenna, and (b) is its vertical directivity. 1 Transmitted antenna under test 2 Mobile flying object 3 Radio control transmitter 21 Receiving antenna for electromagnetic field strength measurement 22 Direction adjuster 23 Electromagnetic field strength measuring instrument 24 GPS satellite radio receiver 25 Radio control receiver 26 Compass 27 Flight plan 28 Information processing device 29 Pilot control 30 Recording / transmission of measured values

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-1-282470 (JP, A) JP-A-4-90978 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 29/10

Claims (4)

(57) [Claims] When measuring the radiation characteristics of a transmitting antenna in an operation state, an automatic or remote controllable device equipped with a device for measuring at least three-dimensional position information and electromagnetic field intensity is provided in the vicinity of or near the transmitting antenna to be measured. The aircraft is made to orbit, and the three-dimensional position information of the aircraft is measured by a satellite radio receiver mounted on the aircraft capable of receiving radio waves from at least three GPS satellites. The electromagnetic field intensity due to the radio wave radiated from the measurement transmission antenna is measured by an electromagnetic field intensity measurement device mounted on the flying object and a reception antenna adjusted in the direction toward the transmission antenna to be measured, and a series of the three-dimensional measurement is measured. The position information and the electromagnetic field strength are temporarily stored in a memory, and after measuring a predetermined number of pairs of three-dimensional position information and the electromagnetic field strength, the data stored in the memory is output. Processing method for calculating the radiation characteristics of the transmitting antenna, wherein the measuring method of the transmitting antenna radiation characteristics using GPS is performed. 2. The measuring method according to claim 1, wherein another GPS satellite radio receiver having the same performance as that of the GPS satellite radio receiver is further installed on the ground near the transmission antenna under test. A method for measuring a transmission antenna radiation characteristic using a GPS, wherein the inherent error from the GPS satellite is canceled by using also the position information of the specific point measured. 3. The measuring method according to claim 1, wherein the receiving antenna is rotated at a constant period within a plane of polarization of the received radio wave, and a positive value is obtained from the time-discrete measured data of the electromagnetic field intensity. A method of measuring a radiation characteristic of a transmitting antenna using GPS, wherein data at the moment of the transmission is estimated. 4. The measuring method according to claim 1, wherein said receiving antenna is partially surrounded by a radio wave absorber to reduce a measurement error caused by reflection of radio waves from the ground. A method for measuring the transmission antenna radiation characteristics using the characteristic GPS.