JP2000214201A - Antenna measuring method and measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring method and measuring apparatus which can evaluate antenna performance in a short time without requiring a peculiar apparatus. SOLUTION: A rotary shaft 16 and a false man body 5 fixed thereto are vertically fitted to a prop 15 vertically fitted onto a turn table 4, and by use of a measuring apparatus structured so that the rotary shaft 16 can be fixed in directions of a plurality of the division numbers n, radial directivity of an antenna is measured. By use of Gθ (θ ϕi) and Gϕ (θ, ϕi) as a vertical polarized wave (θ) component and a horizontal polarized wave (θ) component of a power directivity of the antenna within the resultant i-th azimuth angle face; Pθ(θ, ϕi) and Pϕ (θ, ϕi) as an angle density function of a θ component and a ϕ component of an arrived wave incident on the antenna within the i-th azimuth angle face; and an intersecting polarized wave power ratio XPR, a radiation efficiency ηand an average effective gain Ge' are calculated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for measuring an antenna for a portable terminal, and more particularly to a method for evaluating an effective gain, a radiation efficiency or a correlation coefficient in a short time without requiring a special apparatus. The present invention provides a measuring method and a measuring device that can perform the measurement.

[0002]

2. Description of the Related Art Conventionally, a random field method is known as one of the methods for evaluating the performance of a mobile terminal antenna in a multiplex wave environment. As an example of this method, for example, as shown in Japanese Patent Application Laid-Open No. 4-285868, a scatterer is placed indoors in a measurement space to create a multi-wave environment, and evaluation is performed based on the difference between the reception levels of the antenna under measurement and the reference antenna. How to do was known. Further, as another example, as shown in, for example, an antenna system for mobile communication, Sogo Denshi Publisher, pp. 200-201, a method of performing measurement while moving in an actual multi-wave environment such as an urban area is known. Had been.

As another evaluation method, a radiation efficiency measuring method is known. In this method, the power input to the antenna to be measured is defined as Pin, and the integrated value of the radiated power radiated from the antenna measured over the entire solid angle is defined as Pr.
The radiation efficiency is determined from the ratio of Pr to Pin. As an example of an apparatus for measuring the radiation from the antenna over the entire solid angle in this method, for example, as shown in JP-A-2-62970, JP-A-1-185451, JP-A-2-163668, JP-A-2-54178 And a special mechanism capable of rotating the antenna in all azimuth and elevation directions are known.

As another evaluation method, for example, as shown in Mobile Communication Antenna System, Sogo Denshi Shuppan, pp. 202-203, a radiation pattern of a measured antenna in a horizontal plane is measured and averaged. There has been known a pattern averaging gain evaluation method in which evaluation is performed based on the obtained values.

As another evaluation method, for example,
As shown in 63-165773, a method (cavity method) of arranging an antenna to be measured in a cavity having an opening and measuring an electromagnetic field distribution in front of the opening with a probe is known.

As another evaluation method, for example, as shown in IEICE Transactions B-II, Vol. 81, No. 10, pp. 899, the power directivity of the antenna and the arrival at the antenna are described. There has been known an average effective gain evaluation method in which a value (average effective gain) obtained by integrating the product of the wave angular density functions over all solid angles is obtained by numerical analysis using a computer simulation or the like and evaluated.

As a method of evaluating the correlation coefficient of a diversity antenna, for example, as shown in the IEICE Technical Report, AP98-88, pp.89-96, the power including the phase term of the antenna is used. There has been known a correlation coefficient evaluation method in which a value obtained by integrating the product of the directivity and the angular density function of an incoming wave incident on an antenna over the entire solid angle is numerically analyzed by computer simulation or the like and evaluated.

On the other hand, as a method of measuring a radiation pattern in a specific plane of an antenna, for example, as shown in a mobile communication antenna system, Sogo Denshi Publisher, pp. 194-195, a general anechoic chamber or an open At the site, the antenna to be measured is placed on a table that can be rotated in the azimuth direction, and the measurement antennas corresponding to multiple polarization components are placed at a fixed distance, and the rotation angle and reception level of the table are adjusted. A recording method is used. Although this method has a drawback that a measurable radiation pattern is limited to a specific plane, it is a method in which a measuring device can be measured simply and in a short time.

[0009]

The above-mentioned conventional random field method has a problem that a large-scale measuring device and a great deal of labor are required.

In addition, the above conventional radiation efficiency measuring method has a problem that a large-scale and complicated mechanism and a long measuring time are required to measure the radiation from the antenna over the entire solid angle. . In addition, since a mechanism for rotating a human body or a pseudo human body in all azimuth angles and elevation directions cannot be realized, there is a problem that it is difficult to measure a state in which the portable terminal is mounted on the human body.

In addition, the above-mentioned conventional pattern averaging gain evaluation method and the cavity method have a problem that while the measurement of the state where the portable terminal is worn on the human body is relatively easy, universal and accurate evaluation cannot be performed. .

In addition, the above-mentioned conventional average effective gain evaluation method and correlation coefficient evaluation method are calculated by numerical analysis using an approximate model, and require a large amount of calculation time.
In addition, there is a problem that actual measurement evaluation of an existing antenna cannot be performed. Also, if the power directivity of the antenna over the entire solid angle is obtained by measurement, a large-scale and complicated mechanism device shown in the above-described radiation efficiency measurement method and a lot of measurement time are required.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and provides a measuring method and a measuring apparatus which can evaluate the effective gain, the radiation efficiency or the correlation coefficient in a short time without requiring a special device. For the purpose of providing.

[0014]

Therefore, according to the antenna measuring method of the present invention, the measurement result of the power gain directivity corresponding to the elevation angle θ of the antenna in the specific azimuth plane divided into n and the incident light to the antenna The effective gain is calculated from the angular density function corresponding to the elevation angle θ of the incoming wave.

Further, according to the antenna measuring method of the present invention, n
In the divided i-th azimuth plane, the measurement result Gθ (θ) of the power gain directivity of the vertical polarization component corresponding to the elevation angle θ of the antenna and the vertical polarization corresponding to the elevation angle θ of the incoming wave incident on the antenna Angular density function Pθ (θ) of wave component and coefficient Xθ
Is multiplied to obtain a function Aθ (θ) of θ, and the elevation angle θ of the antenna
Measurement result G of power gain directivity of horizontal polarization component corresponding to
A function Aφ (θ) of θ is obtained by multiplying φ (θ) by an angular density function Pφ (θ) of a horizontal polarization component corresponding to an elevation angle θ of an incoming wave incident on the antenna and a coefficient Xφ, and the Aθ (θ) Is added to Aφ (θ) to obtain a function B (θ) of θ.
(Θ) is multiplied by Sin θ, θ is integrated in the elevation direction in the range of 0 to 180 degrees to obtain a function C (i) of the azimuth plane number i, and i of C (i) is 1 to n Is multiplied by 2π and divided by n to obtain an effective gain.

Further, in the antenna measuring method of the present invention, an angular density function having a uniform distribution in the azimuth direction and a Gaussian distribution in the elevation direction is used.

In the antenna measuring method of the present invention, the coefficient Xθ and the coefficient Xφ are set to values calculated from the cross polarization power ratio.

In the antenna measuring method according to the present invention, n is set to 4.

In the antenna measuring method of the present invention, the above n is set to 8.

Further, in the antenna measuring device of the present invention, the antenna measuring device is configured using the above-described antenna measuring method.

In the antenna measuring apparatus of the present invention, as a mechanism for mounting and rotating the antenna to be measured, there is provided a means for fixing the pseudo human body at a plurality of angles on a turntable rotating in the horizontal direction, The antenna to be measured is fixed.

Further, in the antenna measuring apparatus according to the present invention, in the above antenna measuring apparatus, the rotating shaft and the simulated human body fixed to the support mounted on the turntable are mounted on the surface of the turntable and the support. The rotation axes are parallel to each other, and the rotation axes are fixed at a plurality of vertical angles.

Further, the antenna measuring apparatus of the present invention comprises a rotating shaft movable on an arc-shaped rail mounted on a turntable and a simulated human body fixed to the rotating shaft, wherein the rotating shaft is fixed at a plurality of angles. It is configured to be.

The antenna measuring apparatus according to the present invention is the above-described antenna measuring apparatus, wherein as a measuring method for evaluating radiation efficiency, a power corresponding to an elevation angle θ of the antenna in a specific azimuth plane divided into n is used. The radiation efficiency is calculated from the measurement result of the gain directivity.

In the antenna measuring apparatus of the present invention, the above n is set to 4.

In the antenna measuring apparatus according to the present invention, the above n is set to 8.

Further, the antenna measuring apparatus of the present invention uses the above-described antenna measuring apparatus, wherein the measuring method for evaluating the effective gain of the antenna is used.

Further, according to the antenna measuring method of the present invention, n
Elevation angle θ of antenna in specific divided azimuth plane
The correlation coefficient is calculated from the measurement result of the power gain directivity corresponding to the above and the angular density function corresponding to the elevation angle θ of the arriving wave incident on the antenna.

The antenna measuring apparatus according to the present invention uses the above-described antenna measuring apparatus and the measuring method for evaluating the correlation coefficient.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a measuring method for evaluating an effective gain of an antenna,
Calculation of the effective gain from the power gain directivity measurement result corresponding to the elevation angle θ of the antenna in the specific azimuth plane divided into n and the angular density function corresponding to the elevation angle θ of the incoming wave incident on the antenna. This is a characteristic antenna measurement method, and the effective gain can be evaluated in a short time without requiring a special device.

According to the second aspect of the present invention, i divided into n
Measurement result Gθ (θ) of the power gain directivity of the vertical polarization component corresponding to the elevation angle θ of the antenna in the azimuth plane
And the coefficient Xθ multiplied by the angular density function Pθ (θ) of the vertical polarization component corresponding to the elevation angle θ of the incoming wave incident on the antenna, and θ
Aθ (θ), the measurement result Gφ (θ) of the power gain directivity of the horizontal polarization component corresponding to the elevation angle θ of the antenna and the angle of the horizontal polarization component corresponding to the elevation angle θ of the incoming wave incident on the antenna The density function Pφ (θ) is multiplied by a coefficient Xφ to obtain a function Aφ (θ) of θ, and the Aθ (θ) is added to the Aφ (θ) to obtain a function B (θ) of θ. To Sinθ
And θ is integrated in the elevation direction in the range of 0 to 180 degrees to obtain a function C (i) of the azimuth plane number i, and 2π is added to the sum of the C (i) where i is 1 to n. 2. The antenna measuring method according to claim 1, wherein a value obtained by multiplying and dividing by n is used as an effective gain, and the effective gain can be evaluated in a short time without requiring a special device.

According to a third aspect of the present invention, there is provided an antenna measuring method according to the first or second aspect, wherein an angular density function having a uniform distribution in an azimuth direction and a Gaussian distribution in an elevation direction is used. It is possible to evaluate the effective gain in a short time without requiring a simple device.

The invention according to claim 4 is the antenna measurement method according to claims 2 or 3, wherein the coefficient Xθ and the coefficient Xφ are set to values calculated from the cross polarization power ratio. It is possible to evaluate the effective gain in a short time without requiring a simple device.

The invention according to claim 5 is the antenna measurement method according to any one of claims 1 to 4, wherein n is set to 4, and the effective gain is evaluated in a short time without requiring any special device. can do.

The invention according to claim 6 is the antenna measurement method according to any one of claims 1 to 4, wherein n is set to 8, and the effective gain is evaluated in a short time without requiring a special device. can do.

The invention according to claim 7 is the invention according to claims 1 to 6
An antenna measuring apparatus characterized by using the above-described antenna measuring method, which can provide a measuring apparatus capable of evaluating an effective gain in a short time without requiring a special apparatus.

The invention according to claim 8 is characterized in that the mechanism for mounting and rotating the antenna to be measured includes a turntable that rotates in the horizontal direction, and means for fixing the simulated human body at a plurality of angles on the turntable. An antenna measuring apparatus characterized in that an antenna to be measured is fixed to the pseudo human body, and a power gain directivity corresponding to an elevation angle θ of the antenna in a specific azimuth plane of the antenna arranged near the human body is specially adjusted. The measurement can be performed in a short time without using a special device.

According to a ninth aspect of the present invention, there is provided a power transmission apparatus comprising: a support mounted on a turntable; a rotation shaft mounted on the support; and a simulated human body fixed to the rotation shaft; 9. The antenna measuring apparatus according to claim 8, wherein the rotation axis attached to the support is parallel, and the rotation axis is fixed at a plurality of vertical angles. The power gain directivity corresponding to the elevation angle θ of the antenna in the specific azimuth plane can be measured in a short time without requiring a special device.

According to a tenth aspect of the present invention, there is provided an arc-shaped rail mounted on a turntable, a rotating shaft movable on the rail, and a pseudo human body fixed to the rotating shaft. 9. The antenna measuring apparatus according to claim 8, wherein the axis is fixed at a plurality of angles, and the power gain directivity corresponding to the elevation angle θ of the antenna in a specific azimuth plane of the antenna arranged near the human body. Can be measured in a short time without requiring a special device.

An eleventh aspect of the present invention is the antenna measuring apparatus according to the eighth to tenth aspects, wherein the elevation angle θ of the antenna in a specific azimuth plane divided into n is used as a measuring method for evaluating the radiation efficiency. This is an antenna measurement device that calculates the radiation efficiency from the measurement result of the power gain directivity corresponding to the antenna, and measures the radiation efficiency of the antenna placed near the human body in a short time without requiring any special device can do.

According to a twelfth aspect of the present invention, there is provided the antenna measuring apparatus according to the eleventh aspect, wherein n is set to 4, wherein the radiation efficiency of the antenna disposed near the human body is measured by a special apparatus. It can be measured in a short time without need.

According to a thirteenth aspect of the present invention, there is provided the antenna measuring apparatus according to the eleventh aspect, wherein n is set to 8, wherein the radiation efficiency of the antenna arranged near the human body is measured by a special device. It can be measured in a short time without need.

According to a fourteenth aspect of the present invention, there is provided the antenna measuring apparatus according to the eighth to tenth aspects, wherein the antenna measuring method according to the first to sixth aspects is used as a measuring method for evaluating an effective gain of the antenna. An antenna measuring apparatus characterized in that an effective gain of an antenna arranged near a human body can be measured in a short time without requiring a special apparatus.

According to a fifteenth aspect of the present invention, there is provided a measuring method for evaluating a correlation coefficient of an antenna, wherein the power gain directivity corresponding to the elevation angle θ of the antenna in a specific azimuth plane divided into n is measured. This is an antenna measurement method characterized by calculating the correlation coefficient from the result and the angular density function corresponding to the elevation angle θ of the arriving wave incident on the antenna. Can be evaluated.

According to a sixteenth aspect of the present invention, in the antenna measuring apparatus according to the eighth to tenth aspects, the antenna measuring method according to the fifteenth aspect is used as a measuring method for evaluating a correlation coefficient. Antenna measurement device,
The effective gain of an antenna arranged near a human body can be measured in a short time without requiring any special device.

Hereinafter, embodiments of the present invention will be described.

(First Embodiment) FIG. 1 shows a general structure and coordinates of an antenna for a portable terminal measured by the antenna measuring method and the measuring apparatus according to the first embodiment. In FIG. 1, 1 denotes a whip antenna, 2 denotes a mobile terminal housing,
α and β indicate inclination angles of the whip antenna 1 and the portable terminal housing 2 in the elevation (θ) direction and the azimuth (φ) direction.
Lw indicates the length of the whip antenna 1 and Lz indicates the length of the portable terminal housing 2 in the longitudinal direction. In the present embodiment, it is assumed that the whip antenna 1 is formed of a rod-shaped conductor and the mobile terminal housing 2 is formed of a rectangular parallelepiped conductor. Generally, the length Lw of the whip antenna 1 is ２
The wavelength is set to a wavelength to a quarter wavelength, but is set to a quarter wavelength in the present embodiment. It is known that the radiation characteristic from the portable terminal configured as described above changes depending on the length Lz of the portable terminal housing 2.

An azimuth plane divided into n parts in the azimuth direction in the coordinate system shown in FIG. 1 is defined as shown in FIG. Where G
θ (θ, φi) and Gφ (θ, φi) are the measured values of the vertical polarization (θ) component and the horizontal polarization (φ) component of the power directivity of the antenna in the ith azimuth plane, and Pθ (θ , Φi)
And Pφ (θ, φi) are the angular density functions of the θ component and φ component of the incoming wave incident on the antenna in the i-th azimuthal plane, and the average effective gain G by the measurement method of the present invention is
The basic expression for e ′ is expressed as follows.

[0049]

(Equation 1)

In (Equation 1), XPR is a cross polarization power ratio, and n is an integer of 2 or more.

Here, when n is set to 4, Gθ
For (θ, φi) and Gφ (θ, φi), for example, a result of measuring a radiation pattern of two planes of the XZ plane and the YZ plane in the coordinate system of FIG. 1 can be used. Therefore, for this measurement, a radiation pattern measuring method in a specific plane which can be measured in a short time by a conventionally known measuring device can be used.

Further, Pθ (θ, φi) and Pφ (θ, φ
For example, as shown in FIG. 3, i) is an angular density function that is uniform in the azimuth direction and Gaussian distributed in the elevation direction, and is given by the following equation. Here, in FIG. 3, the horizontal axis is the angle, and the vertical axis is the incoming wave power density.

[0053]

(Equation 2)

[0054]

(Equation 3)

In (Equation 2) and (Equation 3), Aθ and Aφ are proportional constants, mv and mH are average elevation angles of the θ and φ polarization component distributions, and σv and σH are the average elevation angles of the θ and φ polarization component distributions. Standard deviation.

XPR is defined as the ratio of the average received power of the θ component and φ component of the arriving wave.

The average effective gain Ge ′ obtained by the above-described measuring method indicates a time-average antenna gain from the viewpoint of the receiving sensitivity of the antenna for the portable terminal in the multiplex wave propagation path. Is an effective index.

On the other hand, in the conventional method for evaluating the effective gain (Transactions of the Institute of Electronics, Information and Communication Engineers, B-II, Vol. 81, No. 10, pp. 899),
The average effective gain Ge is defined by the following equation.

[0059]

(Equation 4)

In equation (4), Gθ (θ, φ) and Gθ
φ (θ, φ) are the θ and φ components of the power directivity of the antenna over the entire solid angle. So, in this case,
By setting the number n of the azimuth planes in FIG.
It is necessary to evaluate (θ, φ) and Gφ (θ, φ).
Therefore, it is necessary to obtain a numerical analysis by computer simulation or the like, or to use a large-scale measuring device capable of measuring over the entire solid angle.

Here, a calculation result example will be described. FIG. 4 shows a result obtained by calculating the average effective gain Ge in the state where the portable terminal shown in FIG. 1 is held near the human head by hand and tilted from the vertical direction by the tilt angle α by (Equation 4). FIG.
In the graph, the horizontal axis represents the inclination angle α of the portable terminal from the vertical direction, and the vertical axis represents the average effective gain Ge. Where Gθ
(Θ, φ) and Gφ (θ, φ) are obtained by numerical analysis using a computer over the entire solid angle. In addition, the operating frequency is set to 90
0 MHz, and the length Lz of the mobile terminal housing 2 is set to 3/4 wavelength. Further, mv and mH are set to 0 degrees, and σv and σ
H is set to 40 degrees, and XPR is set to -9 dB. FIG.
As shown in the figure, the average effective gain tends to increase as α increases.

Next, in the same state as above, FIG. 5 shows the result of obtaining the average effective gain Ge ′ by the measurement method of the present invention using (Equation 1). In FIG. 5, the horizontal axis is the inclination angle α of the portable terminal from the vertical direction, and the vertical axis is the average effective gain Ge ′. Here, the division number n of the azimuth plane shown in FIG. 2 is set to 4, and Gθ (θ, φi) and Gφ (θ,
φi) is 2 of the XZ plane and the YZ plane in the coordinate system of FIG.
The result of measuring the radiation pattern of the surface is used. Note that this measurement uses a radiation pattern measuring method in a specific plane, which can be measured easily and in a short time by a conventionally known measuring device. Also, the operating frequency, Lz, mv and mH, σv
, ΣH, and XPR are set the same as in FIG. From FIG. 5, the average effective gain Ge ′ obtained by the measurement method of the present invention is shown.
Shows a tendency to increase as α increases, as in FIG. In addition, in the vicinity of 60 degrees where the inclination angle α is generally used by the portable terminal, Ge and Ge ′ show values whose absolute values are extremely close. As described above, the average effective gain Ge ′ by the measurement method of the present invention is very close to the result of the conventional evaluation method, and indicates the antenna performance of the mobile terminal antenna in the multiplex wave propagation environment with sufficient accuracy.

As described above, the characteristic of the measuring method according to the present embodiment is that the effective gain of a mobile terminal antenna in a multiplex wave propagation environment can be evaluated in a short time with sufficient accuracy without requiring a large-scale special device. What you can do.

In addition, by providing the conventional in-plane radiation pattern measuring apparatus with an arithmetic unit incorporating the above-described measuring method of the present invention, a measuring apparatus capable of evaluating an effective gain in a short time without requiring a special apparatus. An apparatus can be provided.

Note that the number of divisions n of the azimuth plane is not limited to the value shown in the present embodiment, and the same effect can be obtained as long as it can be measured in a short time by a simple in-plane radiation pattern measuring apparatus. Is obtained.

The angular density function is not limited to the function described in the present embodiment, and similar effects can be obtained as long as the required evaluation accuracy can be obtained by other functions.

(Second Embodiment) An antenna measuring apparatus according to a second embodiment will be described with reference to FIGS. FIG. 6 is a diagram showing the configuration of the entire antenna measuring apparatus according to the second embodiment, wherein 3 is an antenna unit to be measured, 4 is a turntable, 5 is a simulated human body, 6 is a portable terminal, 7 is a receiving antenna, 8 Is a motor, 9 is a receiver, 10 is a CPU, 11
Denotes a rotation control unit, 12 denotes a display unit, and 13 denotes an anechoic chamber.
In FIG. 6, reference numeral 13 denotes a radio wave anechoic chamber whose six surfaces are covered with a radio wave absorber, which has a dimension sufficiently larger than the wavelength of the measurement frequency. The turntable 4 is rotated in the horizontal direction by a motor 8, and the rotation angle is controlled by a rotation control unit 11. Generally, the rotation angle is controlled at a maximum of 360 degrees, and the angle resolution is about 0.1 to 1 degree. Simulated human body 5
In general, a resin container is filled with a medium (for example, physiological saline) close to the electric constant of the human body. The simulated human body 5 is mounted on the turntable 4 such that the head is oriented in the horizontal direction (Z direction in FIG. 7). Radio waves are radiated from the portable terminal 6 attached close to the simulated human body 5. The receiving antenna 7 is generally configured to be able to select either horizontal polarization or vertical polarization. The receiving antenna 7 receives the vertical polarization component or the horizontal polarization component of the radio wave radiated from the portable terminal 6 and
Will detect that level. The detected level is input to the CPU 10. The CPU 10 displays the radiation pattern on the display unit 12 by comparing the detected level with the rotation angle instructed by the rotation control unit 11.

FIG. 7 is a diagram showing the measured antenna section 3 in FIG. 6 in detail. In FIG. 7, components denoted by the same reference numerals as those in FIG. 6 perform the same operation, 14 denotes a rotating plate, 15 denotes a support, and 16 denotes a rotating shaft. In FIG.
The rotating plate 14, the support 15 and the rotating shaft 16 are formed of a radio wave transparent material (eg, acrylic resin). The support 15 is vertically attached to the turntable 4. A rotating shaft 16 is attached to the column 15, and the rotating shaft 16 can be manually rotated and can be temporarily fixed at an angle divided into n in the vertical direction (the φ direction in FIG. 7). Rotary axis 1
The rotating plate 14 is fixed to 6, and the simulated human body 5 is fixed to the rotating plate 14.

In the above configuration, the rotation shaft 16 is set to the i-th angle divided into n. In this case, by rotating the turntable 4 in the horizontal direction (the θ direction in FIG. 7), the antenna power directivities Gθ (θ, φi) and Gφ in the elevation (θ) direction in the i-th azimuthal plane are obtained.
(Θ, φi) can be measured. Here, since the simulated human body is arranged horizontally (the Z direction is the horizontal direction), when measuring the vertical polarization component Gθ (θ, φi) of the directivity, the receiving antenna 7 is set to the horizontal polarization. However, when measuring the horizontal polarization component Gφ (θ, φi) of the directivity, it is necessary to set the receiving antenna 7 to vertical polarization.

In the antenna measuring apparatus shown in FIG. 7, when realizing the radiation efficiency measuring method for measuring the power directivity over the entire solid angle conventionally known, n is set to the largest possible value (for example, 32). (The azimuth angle resolution must be increased). For this reason, the conventional radiation efficiency measurement method required a large-scale and complicated structure. However, in the case of a mobile terminal antenna placed near the human body,
It is known that the power directivity in the azimuth plane has a relatively small amplitude and a slow fluctuation. Here, FIGS. 8 and 9
FIG. 9 shows calculation results of the radiation efficiency and the effective gain when the number n of divisions of the azimuth plane is changed. 8 and 9, n
The error when n is set to 4 is within about 3 dB at the maximum with respect to the radiation efficiency or effective gain when is set to 32. When n is set to 8, the error is about 0.5.
It is within 1 dB. Therefore, in the antenna measuring apparatus shown in FIG. 7, by setting the n to an appropriate value (for example, 4 or 8) and calculating the radiation efficiency from the measurement result, the radiation efficiency or the effective gain with necessary and sufficient accuracy can be easily obtained. Measurement in a short time with a simple device.

As described above, one of the characteristics of the measuring apparatus according to the present embodiment is that the power gain directivity corresponding to the elevation angle θ in a specific azimuth plane of the antenna arranged near the human body is simplified. The measurement can be performed in a short time by the device. Another feature is that by setting n to an appropriate value (for example, 4 or 8), radiation efficiency or effective gain with sufficient accuracy can be measured in a short time with a simple device.

Note that the number n of divisions of the azimuth plane is not limited to the value shown in the present embodiment, and a similar effect can be obtained as long as necessary and sufficient accuracy can be obtained and the measurement can be performed in a short time. Can be

The turntable and the simulated human body are not limited to the configuration shown in the present embodiment, and the same effect can be obtained as long as the configuration performs the same operation.

Further, in this embodiment, it is assumed that the simulated human body is manually rotated. However, if the mechanism is configured to be automatically rotated by a motor or the like, the configuration becomes slightly complicated, but the measuring time is further reduced. be able to.

Further, the configuration of the receiving antenna, the receiver, the CPU, the display unit, and the rotation control system is not limited to the configuration shown in this embodiment, and the same effect can be obtained as long as the configuration performs the same operation.

Further, in the present embodiment, the apparatus is constructed in an anechoic chamber. However, for example, the same effect can be obtained in an open site.

(Third Embodiment) An antenna measuring apparatus according to a third embodiment will be described with reference to FIGS. 6, 10 and 11. 10 and 11 are diagrams showing the measured antenna section 3 in FIG. 6 in detail. 10 and 1
In FIG. 1, components denoted by the same reference numerals as those in FIGS. 6 and 7 perform the same operation, 17 and 18 denote rails, and 19 denotes a bearing. The rails 17, 18 and the bearing 19 are formed of a radio wave transparent material (eg, acrylic resin). The rails 17 and 18 are formed in an arc shape so that the turntable 4
Fixed on top. The rail 17 is supported by a structure that can move on the rail 18 and constitutes a stretchable arc-shaped rail. The structural bearing 19 is supported by a structure movable on the rail 17. The rotating shaft 16 is attached to the bearing 19. In FIG. 10, the rails 17 and 18 are extended, and the simulated human body 5 is fixed so that the vertical (Z) direction is horizontal. On the other hand, in FIG. 11, the rails 17 and 18 are shortened, and the simulated human body 5 is fixed so that the vertical (Z) direction is directed to the vertical direction.

In general, the radiation efficiency or effective gain of a mobile terminal antenna placed near a human body is calculated from the antenna power directivity in the elevation (θ) direction in a specific azimuth (φ) plane. However, as a method for performing a simple evaluation, an evaluation for calculating a pattern averaging gain from antenna power directivity (directivity in a horizontal plane) in an azimuth (φ) direction at a specific elevation angle (generally, θ = 90 degrees). A method may be used.

Here, in the state shown in FIG. 10, by rotating the turntable 4 in the horizontal direction (the θ direction in FIG. 10), the antenna power directivity in the elevation (θ) direction in the i-th azimuth plane is obtained. Gθ (θ, φi) and Gφ
(Θ, φi) can be measured. From this result, the radiation efficiency or the effective gain can be calculated and evaluated. On the other hand, in the state of FIG. 11, by rotating the turntable 4 in the horizontal direction (the φ direction in FIG. 11), the antenna power directivity Gθ (θ = θ) in the azimuth (φ) direction at an elevation angle (θ) of 90 degrees. 90 degrees, φ) and Gφ (θ = 90 degrees,
φ) can be measured. From this result, the pattern averaging gain in the horizontal plane can be calculated and evaluated. In this case, the rails 17 and 18 are shortened, and do not affect the radio waves radiated from the portable terminal 6.

As described above, the feature of the measuring apparatus according to the present embodiment is that the elevation angle (θ) in a specific azimuth plane is set.
Both the power gain directivity in the direction and the power directivity in the azimuth (φ) direction at a specific elevation angle can be measured in a short time using the same simple device.

Note that the specific elevation angle (θ = 90 degrees) is not limited to the value shown in the present embodiment, and similar effects can be obtained with other values.

The configuration of the rail is not limited to the configuration shown in the present embodiment, and the same effect can be obtained as long as the configuration performs the same operation.

In the present embodiment, it is assumed that the rails are manually moved. However, if a mechanism for automatically providing guidance by a motor or the like is used, the configuration is slightly complicated, but the measurement time can be further reduced. Can be.

(Fourth Embodiment) An antenna measuring apparatus according to a fourth embodiment will be described with reference to FIG. FIG.
2 is a diagram showing the configuration of the entire antenna measuring apparatus according to the fourth embodiment, and those denoted by the same reference numerals as those in FIG. 6 perform the same operations. In FIG. 12, reference numeral 20 denotes, for example, a network analyzer, which is an apparatus for measuring both the amplitude term and the phase term of the transmission characteristic from the portable terminal 6 to the receiving antenna 7. The measurement procedure of the antenna measuring apparatus shown in FIG. 12 is the same as that of the antenna measuring apparatuses of the second and third embodiments shown in FIG. 6, but the transmission characteristic obtained as a result of the measurement has an amplitude term and a phase term. Is different.

In the above configuration, two antennas (antenna 1 and antenna 2) constituting the diversity antenna of the portable terminal 6 are measured. Here, as a measurement result of the antenna 1, the vertical polarization (θ) component and the horizontal polarization (φ) component of the complex power directivity in the elevation (θ) direction in the i-th azimuth plane are expressed as Eθ1 (θ, φi) and Eφ
1 (θ, φi). Also, as the measurement results of the antenna 2, the vertical polarization (θ) component and the horizontal polarization (φ) of the complex power directivity in the elevation (θ) direction in the ith azimuth plane are shown.
The components are Eθ2 (θ, φi) and Eφ2 (θ, φi). Further, if Pθ (θ, φi) and Pφ (θ, φi) are the angular density functions of the θ component and φ component of the arriving wave incident on the antenna in the i-th azimuthal plane, the phase by the measurement method of the present invention is obtained. A basic expression for obtaining the relation number ρe is expressed as the following expression.

[0086]

(Equation 5)

In the equation (5), XPR is a cross polarization power ratio, and n is an integer of 2 or more. * Indicates a conjugate complex number. Also, Pθ (θ, φi) and Pφ (θ, φ
i) is represented by an angular density function that is uniform in the azimuth direction and Gaussian distributed in the elevation direction, and is given by (Equation 2) and (Equation 3) as in the first embodiment.

Here, when n is set to 4, Eθ1
(Θ, φi), Eφ1 (θ, φi), Eθ2 (θ, φ
For i) and Eφ2 (θ, φi), for example, a result obtained by measuring a radiation pattern on two surfaces of the XZ plane and the YZ plane in the coordinate system of FIG. 1 can be used. Therefore, for this measurement, a radiation pattern measuring method in a specific plane which can be measured in a short time by a conventionally known measuring device can be used.

As described above, the characteristic of the measuring apparatus according to the present embodiment is that by setting n to an appropriate value, a correlation coefficient with necessary and sufficient accuracy can be measured in a short time with a simple apparatus. .

The number n of divisions of the azimuth plane is not limited to the value shown in the present embodiment, and the same effect can be obtained as long as necessary and sufficient accuracy can be obtained and the measurement can be performed in a short time. Can be

In the present embodiment, a network analyzer is used as a means for measuring the complex power directivity. However, the present invention is not limited to this, and other means, such as a vector volt meter, can obtain the same effect. .

Further, the angular density function is not limited to the function described in the present embodiment, and similar effects can be obtained as long as the required evaluation accuracy can be obtained by other functions.

[0093]

As is apparent from the above description, according to the present invention, it is possible to provide a measuring method and a measuring apparatus which can evaluate the effective gain in a short time without requiring a special device.

Further, the power gain directivity corresponding to the elevation angle in a specific azimuth plane can be measured in a short time with a simple device.

Further, the radiation efficiency, the effective gain, and the correlation coefficient with necessary and sufficient accuracy can be measured in a short time with a simple device.

Further, both the power gain directivity in the elevation direction within a specific azimuth plane and the power directivity in the azimuth direction at a specific elevation angle can be measured in a short time by using the same simple apparatus.

[Brief description of the drawings]

FIG. 1 is a diagram showing a structure and coordinates of a mobile terminal antenna measured by an antenna measuring method and a measuring apparatus according to a first embodiment.

FIG. 2 is a diagram showing an azimuth plane divided into n parts in an azimuth direction;

FIG. 3 is a diagram showing an angular density function of an incoming wave in an elevation angle direction;

FIG. 4 is a diagram showing an average effective gain obtained by a conventional evaluation method.

FIG. 5 is a diagram showing an average effective gain obtained in the first embodiment.

FIG. 6 is a diagram showing a configuration of an entire antenna measuring apparatus according to the second and third embodiments.

FIG. 7 is a diagram illustrating details of an antenna measurement device according to a second embodiment.

FIG. 8 is a diagram showing calculation results of radiation efficiency with respect to the number of divisions n in the second embodiment.

FIG. 9 is a diagram showing a calculation result of an effective gain with respect to the number of divisions n in the second embodiment.

FIG. 10 is a diagram showing details of an antenna measurement device according to a third embodiment.

FIG. 11 is a diagram showing details of an antenna measurement device according to a third embodiment.

FIG. 12 is a diagram illustrating a configuration of an entire antenna measuring apparatus according to a fourth embodiment;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 whip antenna 2 mobile terminal housing 3 antenna under test 4 turntable 5 artificial human body 6 mobile terminal 7 receiving antenna 8 motor 9 receiver 10 CPU 11 rotation control unit 12 display unit 13 anechoic chamber 14 rotating plate 15 support 16 rotation axis 17, 18 rail 19 bearing 20 network analyzer

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Yoshio Koyanagi 4-3-1, Amishimahigashi, Kohoku-ku, Yokohama-shi, Kanagawa Prefecture Inside Matsushita Communication Industrial Co., Ltd. Matsushita Electric Industrial Co., Ltd.

Claims (16)

[Claims] 1. A measurement method for evaluating an effective gain of an antenna, comprising: a measurement result of a power gain directivity corresponding to an elevation angle θ of an antenna in a specific azimuth plane divided into n;
An antenna measurement method comprising calculating an effective gain from an angular density function corresponding to an elevation angle θ of an incoming wave incident on an antenna. 2. A measurement result Gθ (θ) of a power gain directivity of a vertically polarized component corresponding to an elevation angle θ of an antenna in an i-th azimuth plane divided into n, and an elevation angle of an incoming wave incident on the antenna. Angular density function Pθ of vertical polarization component corresponding to θ
(Θ) is multiplied by a coefficient Xθ to obtain a function Aθ (θ) of θ,
The measurement result Gφ (θ) of the power gain directivity of the horizontal polarization component corresponding to the elevation angle θ of the antenna and the angular density function Pφ of the horizontal polarization component corresponding to the elevation angle θ of the incoming wave incident on the antenna
(Θ) is multiplied by a coefficient Xφ to obtain a function Aφ (θ) of θ,
Aθ (θ) is added to Aθ (θ) to obtain a function B of θ.
(Θ), and B (θ) is multiplied by Sin θ to obtain θ
A function C (i) of the azimuth plane number i by integrating in the elevation direction in the range of degrees to 180 degrees, and a value obtained by multiplying the sum of the above C (i) from 1 to n by 2π and dividing by n. The antenna measuring method according to claim 1, wherein? 3. The antenna measuring method according to claim 1, wherein an angular density function having a uniform distribution in an azimuth direction and a Gaussian distribution in an elevation direction is used. 4. The coefficient Xθ and the coefficient Xφ are set to values calculated from the cross polarization power ratio.
4. The antenna measuring method according to any one of claims 1 to 3. 5. The antenna measuring method according to claim 1, wherein n is set to 4. 6. The antenna measuring method according to claim 1, wherein n is set to 8. 7. An antenna measuring apparatus using the antenna measuring method according to claim 1. 8. A mechanism for mounting and rotating an antenna to be measured, comprising: a turntable that rotates in a horizontal direction; and means for fixing a pseudo human body at a plurality of angles on the turntable, wherein the antenna to be measured is attached to the pseudo human body. An antenna measuring device, characterized in that: 9. A method according to claim 1, further comprising a support mounted on a turntable, a rotating shaft mounted on the support, and a simulated human body fixed to the rotary shaft, wherein the pseudo human body is mounted on the surface of the turntable and the support. 9. The antenna measuring apparatus according to claim 8, wherein the rotation axes are parallel, and the rotation axes are fixed at a plurality of vertical angles. 10. An arc-shaped rail mounted on a turntable, a rotating shaft movable on said rail,
9. The antenna measuring apparatus according to claim 8, further comprising a pseudo human body fixed to the rotation axis, wherein the rotation axis is fixed at a plurality of angles. 11. The antenna measuring apparatus according to claim 8, wherein the measuring method for evaluating the radiation efficiency is n.
Elevation angle θ of antenna in specific divided azimuth plane
An antenna measuring apparatus for calculating a radiation efficiency from a measurement result of a power gain directivity corresponding to (1). 12. The antenna measuring apparatus according to claim 11, wherein n is set to 4. 13. The antenna measuring apparatus according to claim 11, wherein n is set to 8. 14. An antenna measuring apparatus according to claim 8, wherein the antenna measuring method according to claim 1 is used as a measuring method for evaluating an effective gain of the antenna. apparatus. 15. A measurement method for evaluating a correlation coefficient of an antenna, comprising: a measurement result of a power gain directivity corresponding to an elevation angle θ of an antenna in a specific azimuth plane divided into n parts; An antenna measurement method comprising calculating a correlation coefficient from an angular density function corresponding to an elevation angle θ of an incoming wave. 16. The antenna measuring apparatus according to claim 8, wherein the antenna measuring method according to claim 15 is used as a measuring method for evaluating a correlation coefficient.