JP2001004499A - Testing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain testing equipment for a radio terminal and a base station which can realize improvement in the accuracy of reproduction of a radio environment in a real field, by enabling reduction of an error in the direction of arrival of a path and increase of the total electric power of the path being reproduced. SOLUTION: This testing equipment has a constitution wherein a radio environment in a real field is reproduced in an anechoic chamber 2 wherein a plurality of antennas 11-14 are disposed and, moreover, a constitution wherein it has a path data storage part 6 storing the field intensity of each path and the direction of arrival thereof which are parameters of the radio environment in the real field, a path selection processing part 1 selecting a plurality of paths which can reproduce the above radio environment based on the above parameters and a pseudo-circuit control part 8 which assigns a signal outputted from a simulator 5 operating as a pseudo-base station in the circumference of a radio terminal 1, to each pseudo-circuit 3 according to the path selected and further conducts a control for outputting the signal on the pseudo-circuit from each antenna.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a test apparatus for extracting information for performing an evaluation test from a measurement result of a radio wave environment in a real field and reproducing the information in a laboratory. Like an outdoor evaluation test,
The present invention relates to a test apparatus capable of performing a test under a condition where it is difficult to perform measurement and reproduction in the same radio wave environment in a laboratory.

[0002]

2. Description of the Related Art A conventional test apparatus capable of reproducing a real field environment will be described below. For example, when developing a PHS terminal, a test in an actual field is performed for comprehensive performance evaluation. However, in the actual field, since it is difficult to reproduce the same conditions, much time is spent for performing highly reliable evaluation. Therefore,
In recent years, it has been desired to reproduce a real field environment in a laboratory in order to shorten a test period.

As a conventional test apparatus for reproducing this real field environment in a laboratory, for example, a report of the IEICE General Conference, 1998, General Proceedings B-5-157 "P.
A Study of the HS Field Environment ". FIG. 8 is a diagram showing a configuration of the conventional test apparatus. In FIG. 8, 1
Reference numerals 01 to 103 denote pseudo base stations for transmitting and receiving, and 104
Is a pseudo base station that performs only transmission, 105 to 108 are pseudo lines, 109 is a timing / attenuation control unit, 110 is a shield room, 121 to 121
Reference numeral 123 denotes a transmitting antenna for transmitting a signal from a base station, reference numeral 124 denotes a receiving antenna for receiving a signal from a terminal to be tested, and reference numerals 130, 140, and 150 denote antennas composed of antennas 121 to 124. is there. In addition,
As a terminal to be tested in the test apparatus configured as described above, for example, the PHS terminal 111 is used.

[0004] The operation of the above conventional test apparatus will be described below. For example, signals output from the pseudo base stations 101 to 104 are transmitted through the pseudo lines 105 to 108 to the antennas 121 to 1 installed in the shield room 110.
23, 130, 140 and 150. At this time, the timing / attenuation control unit 109 sets the pseudo base station 1
Adjustment of transmission timings 01 to 104 and control of signal attenuation in the pseudo lines 105 to 108 are performed.

On the other hand, the PHS terminal 1 that has received the test radio wave
Radio waves transmitted from the reception antennas 114 and 13
0, 140, after receiving pseudowires 105-1
07 to the pseudo base stations 101 to 103.
At this time, the timing / attenuation control unit 109 performs signal attenuation control on the pseudo lines 105 to 108.

As described above, in the conventional test apparatus, by performing the above operation, the environment where the base station exists in a pseudo manner,
And a fading environment in a real field can be realized. Thereby, the PHS terminal 1 to be evaluated
In 11, an evaluation test assuming a real field environment can be performed in the shield room 110.

[0007] Further, in order to perform a more accurate evaluation, a conventional test apparatus that reproduces the direction of arrival of a radio wave in a laboratory includes the IEICE Technical Report A / P98-126.
(1998-12) "A Study on a Field Simulator Reproducing the Direction of Arrival". FIG. 9 is a diagram showing an antenna arrangement example of a field simulator (corresponding to a conventional test device), FIG. 10 is a diagram showing the electric field strength and arrival direction of a path obtained by a radio wave propagation simulation, and FIG. 12A and 12B are diagrams illustrating a space around a reception position divided by the number of antennas, and FIGS. 12A and 13B are diagrams illustrating delay profiles in respective regions.

The operation of the conventional test apparatus will be described below with reference to FIGS. 9, reference numeral 201 denotes a wireless terminal to be evaluated; 202, an anechoic chamber;
Is an absorber, and 211 to 214 are antennas. In this test apparatus, a plurality of antennas 211 to 214 are arranged around a wireless terminal 201 in an anechoic chamber 202 whose inside is covered by an absorber 203, and each of the antennas 211 to 214 is a radio wave equivalent to a real environment in the vicinity of the direction. (Radio waves from a plurality of base stations existing in that direction). Specifically, in the case of an example in which four transmission antennas 211 to 214 are arranged, the test apparatus divides the space into four parts in the horizontal plane of the anechoic chamber 202 (see regions (1) to (4) in FIG. 11). Each transmitting antenna emits a radio wave according to the radio wave environment of each area.

At this time, when the conventional test apparatus radiates radio waves corresponding to the real environment, measured values or values estimated by simulation are used as parameters of the radio wave environment radiated from each antenna. Further, for example, when the electric field strength and the direction of arrival as shown in FIG. 10 are estimated by simulation, the conventional test apparatus further shows the delay profiles of radio waves reaching each region in FIGS. 12 and 13. Estimate as follows.

As a result, in the conventional test apparatus, the radio environment corresponding to the real environment including the radio wave arrival direction of the base station around the wireless terminal 201, that is, the electric field strength and the arrival direction of each path shown in FIG. , And an environment corresponding to the delay profiles shown in FIGS. 12 and 13 can be reproduced. In FIG. 10, the line from the center represents a plurality of paths, the direction represents the angle of arrival, and the length of the axis represents the reception level (electric field intensity) of each path. FIG.
FIG. 13 and FIG. 13 show specific examples of the delay profile of each area, in which the horizontal axis represents the path delay time and the vertical axis represents the path reception level.

[0011]

SUMMARY OF THE INVENTION However,
In conventional test equipment, the position of the transmitting antenna is fixed,
Furthermore, since the division of the anechoic chamber space, that is, the path assignment, is simply performed for each direction, it cannot be adjusted or changed according to the situation. Therefore, an error occurs in the direction of arrival of the radio wave,
There is a problem that the accuracy of the direction of arrival of the path when reproducing the propagation environment in the actual field is deteriorated.

Further, in the conventional test apparatus, when the arrival directions of the paths are concentrated in the same direction, it is difficult to reproduce a path having a high power level. As a result, the accuracy of the inspection in the reproduced environment is reduced. There was a problem of deterioration.

The present invention has been made in view of the above, and reduces and reproduces the error in the direction of arrival of a path by making the position of the transmitting antenna variable in the path allocation process and by giving an offset to the angle of arrival. It is an object of the present invention to obtain a test apparatus capable of improving the accuracy of reproduction of a radio wave environment in a real field by enabling an increase in the total power of a path.

[0014]

Means for Solving the Problems To solve the above-mentioned problems,
In order to achieve the object, the test apparatus according to the present invention has a configuration in which a radio wave environment in a real field is reproduced in a radio wave anechoic chamber in which a plurality of antennas are arranged, and a radio terminal and a base station are tested. Further, parameter storage means (corresponding to a path data storage unit 6 in an embodiment described later) for storing the electric field strength and arrival direction of each path, which are parameters of the radio wave environment in the actual field, and the radio wave based on the parameters A path selection means (corresponding to the path selection processing unit 7) for selecting a plurality of paths capable of reproducing the environment, and a signal output from a simulator operating as a pseudo base station around the wireless terminal under test, Transmission line control means (pseudo line) for performing control for outputting signals on the transmission line from the plurality of antennas. And equivalent) to control unit 8, characterized in that it comprises a.

According to the present invention, errors in path arrival directions can be reduced by selecting a plurality of reproducible paths based on the electric field strength, arrival direction, and delay profile of each path in a real field. As a result, it is possible to improve the reproduction accuracy of the radio wave environment in the actual field as compared with the related art.

In the test apparatus according to the next invention, the path selecting means includes a predetermined number of antennas for each antenna unit such that the sum of the angular errors between the arrival direction of the path to be reproduced and the fixed antenna installation positions is minimized. Is selected.

According to the present invention, an offset value is provided in the arrival direction of the radio wave so that the total sum of the angular errors between the arrival direction of the path and the installation antenna radiating position is minimized. To reproduce the radio wave environment in the real field. Thereby, the reproduction accuracy of the radio wave environment in the actual field can be greatly improved.

In the test apparatus according to the next invention, the path selection means selects a predetermined number of paths for each antenna unit so that the total sum of the electric field strengths of the paths reproduced by the fixed antenna installation positions is maximized. It is characterized by doing.

According to the present invention, an offset value is provided in the direction of arrival of the radio wave so that the ratio of the sum of the power levels of the reproduced paths to the sum of the power levels of all the paths is minimized. To reproduce the radio wave environment in the real field. Thereby, the reproduction accuracy of the radio wave environment in the actual field can be greatly improved.

[0020] In the test apparatus according to the next invention, the path selecting means sets a fixed threshold value to the sum of the angle errors (arrival angle errors) between the arrival direction of the path to be reproduced and the fixed antenna installation positions. And selecting a predetermined number of paths for each antenna unit so that the total (power reproduction ratio) of the electric field strengths of the paths reproduced by the fixed antenna installation positions is equal to or less than the threshold value. Features.

According to the present invention, a threshold value that satisfies a certain criterion for the angle of arrival error is provided, and a path that maximizes the power reproduction ratio at an offset angle at which the angle of arrival error is equal to or smaller than the threshold value is selected. As a result, an optimal radio wave environment can be reproduced from both the angle of arrival error and the power reproduction ratio.

In the test apparatus according to the next invention, the path selecting means sets a fixed threshold value to a total sum (electric power reproduction ratio) of the electric field strength of the path reproduced at each fixed antenna installation position, and It is necessary to select a predetermined number of paths for each antenna unit so that the sum of the angles of arrival (errors of arrival) between the direction of arrival of the path to be reproduced and the fixed position of each fixed antenna is minimized. Features.

According to the present invention, a threshold value that satisfies a predetermined criterion for the power reproduction ratio is provided, and a path that minimizes the arrival angle error at an offset angle at which the power reproduction ratio is equal to or greater than the threshold value is selected. As a result, an optimal radio wave environment can be reproduced from both the angle of arrival error and the power reproduction ratio.

[0024] In the test apparatus according to the next invention, the path selecting means preliminarily selects a predetermined number of paths from the paths in the real field in descending order of electric field strength, and thereafter, the arrival direction of the selected path. Each antenna is installed so that the sum of angular errors between the antenna and each movable antenna is minimized.

According to the present invention, the paths are selected in descending order of the power level, and thereafter, the arrangement position of the transmitting antenna from which the selected path radiates is set, so that the power reproduction ratio of the path is always set to the optimum value. be able to. As a result, the reproduction accuracy of the radio wave environment in the actual field can be further greatly improved.

[0026] In the test apparatus according to the next invention, the path selecting means preliminarily selects a predetermined number of paths from the paths in the real field in descending order of electric field strength, and sets a maximum number of paths within a region of each antenna. Each antenna is installed in the direction of arrival of the path of the electric field strength.

According to the present invention, the calculation processing in the path selection means is simplified, and a path can be easily assigned to each antenna.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the test apparatus according to the present invention will be described below in detail with reference to the drawings. In addition,
The present invention is not limited by the embodiment.

Embodiment 1 FIG. 1 is a diagram showing a configuration of a test apparatus according to a first embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a wireless terminal to be tested;
Is an anechoic chamber, 3 is a pseudo line serving as a transmission path for a transmission signal, 4 is a pseudo line serving as a transmission path for a reception signal, and 5 is an operation as a plurality of base stations existing around the wireless terminal. 6 is a path data storage unit that stores parameters of the radio wave environment in the actual field, that is, the electric field strength and arrival direction of each path, and a delay profile, and 7 is stored in the path data storage unit 6. A path selection processing unit for selecting a predetermined path based on the parameters obtained, a pseudo-line control unit 8 for allocating the path selected by the path selection processing unit 7 to each transmission path,
Numerals 11 to 14 are transmission antennas for transmitting radio waves corresponding to the path allocated to the pseudo channel 3, and 21 is a reception antenna for receiving radio waves from the wireless terminal 1. In addition,
Here, the target of the test is a terminal, but is not limited to this.
For example, it may be a base station.

Hereinafter, the operation of the test apparatus configured as described above will be described. First, a signal output from the simulator 5 is transmitted from the antennas 11 to 14 installed in the anechoic chamber 2 via the pseudo line 3. On the other hand, a transmission signal from the wireless terminal 1 to be tested is received by the reception antenna 21 and then transmitted to the simulator 6 via the pseudo line 4.

Here, a case where the wireless terminal 1 performs an evaluation test assuming a real field environment in the anechoic chamber 2 will be described in detail. FIG. 2 shows the arrival direction of each path and its power level (electric field strength) using path data (parameters), that is, values estimated by simulation or actually measured values in a real field. The direction of the line extending from the center of the circle indicates the direction of arrival of each path, and the length indicates the power level.

First, in the test apparatus, in order to set each path in the pseudo line 3, the path data of the radio wave environment in the actual field, that is, the electric field strength and arrival direction of each path, and the delay profile are stored in the path data storage unit. 6 is stored.

In this state, the path selection processing section 7 reads the path data from the path data storage section 6 and selects a specific path from a plurality of paths that can be recognized from the path data by a predetermined method. For example, as shown in FIG. 1, when the transmitting antennas 11 to 14 are installed, that is, when viewed from the wireless terminal 1, 45 degrees, 135 degrees, 225 degrees, and 31 degrees
When the transmitting antennas 11 to 14 are installed in directions of 5 degrees, 0 to 90 degrees, 90 to 18 degrees around the wireless terminal 1.
From a plurality of paths arriving from a range of 0 degrees, 180 degrees to 270 degrees, and 270 degrees to 360 degrees, for example,
Select three paths with higher power levels.

However, in the case of the path data as shown in FIG. 2, if the path selected as described above is allocated to each pseudo line 3 as it is, the angle error between the arrival direction of the path and the installation position of the transmitting antenna is calculated. The sum may be large. That is, the 12 selected as described above
The sum of the angle differences between the directions of arrival of the paths and the directions of the transmission antennas corresponding to those paths as viewed from the wireless terminal 1 is not always in the minimum state.

Therefore, in the present embodiment, an offset angle (value) that minimizes the sum of the above-mentioned angle errors is always obtained, and an offset is given to the path data shown in FIG. From the plurality of recognizable paths, three specific paths (3 × 4 = 12) having a high power level are selected by the above method. That is, based on the offset path data shown in FIG. 3, 0 to 90 degrees and 90 to 18 degrees centered on each antenna, respectively.
From among a plurality of paths arriving from 0 degrees, 180 degrees to 270 degrees, and 270 degrees to 360 degrees, three paths each having a large power level are selected.

It should be noted that a specific example of obtaining the offset angle is as follows.
For example, the angle of arrival error is calculated as follows
There is a way to do that. For example, if the number of antennas is N,
The number of paths that can be radiated from the_iAnd each sending address
Power level in the range covered by the antenna
The power of the k-th path (k = 1 to 3 in the present embodiment)
To P_ikAnd P_ikDirection of arrival and antenna corresponding to
Δθ from the installation direction _ik, Depending on the power level
Angle-of-arrival error weighted by the following equation (1)
be able to.

[0037]

(Equation 1)

Then, the path selection processing unit 7 obtains an offset angle that minimizes the arrival angle error (total of the angle error between the arrival direction of the path and the installation position of the transmitting antenna) represented by the equation (1). . In this case, the same radio wave environment is maintained in the radio wave anechoic chamber 2 as viewed from the wireless terminal 1.

Thereafter, the pseudo line control unit 8 selects the paths selected by the path selection processing unit 7 in the respective paths in the pseudo line 3, that is, path1-1, path1-
Assign to 2, ...

As described above, according to the present embodiment, the offset value is set in the direction of arrival of the radio wave so that the sum of the angle errors between the direction of arrival of the path and the direction of the transmitting antenna installation position radiating the path is minimized. In this state, the radio wave environment in the actual field was reproduced. This allows
Compared with the related art, the accuracy of reproducing the radio wave environment in the actual field can be greatly improved.

Embodiment 2 In the first embodiment, (1)
Although the offset angle is set so as to reduce the arrival angle error obtained by the equation, for example, as shown in the present embodiment described below, a path having a large power level is selected from paths to be reproduced as much as possible. Similar effects can be obtained by setting the offset angle.

Hereinafter, the operation of the test apparatus according to the present embodiment will be described. Here, the test target is a terminal, but is not limited to this, and may be, for example, a base station. Further, the configuration of the test apparatus is the same as the configuration of FIG. 1 described above, and thus the same reference numerals are given and the description is omitted. Here, only operations different from those in the first embodiment will be described.

For example, when the wireless terminal 1 performs an evaluation test assuming a real field environment in the anechoic chamber 2, the test apparatus sets up each path in the pseudo line 3 in order to set each path in the real field. The data, that is, the electric field strength and arrival direction of each path, and the delay profile are stored in the path data storage unit 6.

In this state, the path selection processing section 7 reads the path data from the path data storage section 6 and selects a specific path from a plurality of paths that can be recognized from the path data by a predetermined method. For example, as shown in FIG. 1, when the transmitting antennas 11 to 14 are installed, that is, when viewed from the wireless terminal 1, 45 degrees, 135 degrees, 225 degrees, and 31 degrees
When the transmitting antennas 11 to 14 are installed in the direction of 5 degrees, 0 to 90 degrees, 90 degrees to each antenna center.
From among a plurality of paths arriving from the range of 180 degrees, 180 degrees to 270 degrees, and 270 degrees to 360 degrees, for example, three paths each having a higher power level are selected.

However, in the case of the path data as shown in FIG. 2, if the path selected as described above is allocated to each pseudo line 3 as it is, even if the power level is higher than the currently selected path. Regardless, there are paths that are not selected. That is, the ratio of the sum of the power levels of the twelve paths to be reproduced to the sum of the power levels of all the paths (including the unselected paths) shown in FIG. It is not always the maximum state.

Therefore, in the present embodiment, an offset angle (value) that minimizes the power reproduction ratio is always obtained, and the path data shown in FIG. From the plurality of possible paths, three specific paths each having a large power level (3 × 4 = 12) are selected by the above method. That is, based on the offset path data shown in FIG. 3, 0 to 90 degrees, 90 to 180 degrees around each antenna, respectively.
From among a plurality of paths arriving from the range of 180 degrees to 270 degrees and 270 degrees to 360 degrees, three paths each having a large power level are selected.

As a specific method of obtaining the offset angle, for example, there is a method of calculating the power reproduction ratio as follows. For example, if the number of antennas is N,
The number of paths that can be radiated from each transmitting antenna is M _i, and the power of the k-th (k = 1 to 3 in this embodiment) power level in the range covered by each transmitting antenna is P _ik. In this case, the power reproduction ratio can be expressed by the following equations (2) and (3).

[0048]

(Equation 2)

[0049]

(Equation 3)

Then, the path selection processing unit 7 obtains an offset angle that minimizes the power reproduction ratio represented by the above equation. In this case, the same radio wave environment is maintained in the radio wave anechoic chamber 2 as viewed from the wireless terminal 1. afterwards,
The pseudo line control unit 8 assigns the paths selected by the path selection processing unit 7 to the respective paths in the pseudo line 3, that is, path1-1, path1-2,.

As described above, according to the present embodiment, the ratio of the sum of the power levels of the reproduced paths (in this embodiment, 12) to the sum of the power levels of all the paths is minimized. An offset value is provided in the direction of arrival of a radio wave, and in this state, a radio wave environment in a real field is reproduced. As a result, it is possible to greatly improve the reproduction accuracy of the radio wave environment in the actual field as compared with the related art.

In this embodiment, further,
A threshold value that satisfies a certain criterion is provided for the angle of arrival error (corresponding to equation (1)) calculated in the first embodiment, and the power reproduction ratio at an offset angle at which the angle of arrival error is equal to or smaller than the threshold value. Can be selected by the above-described method. Thereby, in addition to the above-described effects, an optimal radio wave environment can be reproduced from both aspects of the angle of arrival error and the power reproduction ratio.

Conversely, a threshold value that satisfies a certain criterion is provided for the power reproduction ratio (corresponding to equation (2)) calculated in this embodiment, and the power reproduction ratio is equal to or greater than the threshold value. The same effect can be obtained by selecting the path that minimizes the arrival angle error at the offset angle that is given by the above method.

Embodiment 3 FIG. FIG. 4 is a diagram showing a configuration of a test apparatus according to a third embodiment of the present invention. Here, the test target is a terminal, but is not limited to this, and may be, for example, a base station. Further, in the configuration of the present embodiment, the same components as those of Embodiments 1 and 2 described above are denoted by the same reference numerals, and description thereof will be omitted. In FIG. 4, reference numeral 9 denotes a movable range of the transmitting antennas 11 to 14. In this example, the transmitting antenna position is movable concentrically.

Hereinafter, the operation of the test apparatus according to the present embodiment will be described. For example, when the number of transmitting antennas is 4 and the number of paths radiable from each antenna is 3, a maximum of 12 paths can be radiated in the anechoic chamber 2. However, in Embodiments 1 and 2 (the path selected based on FIG. 3), although the path is improved over the path selected based on FIG. 2 (the number of white circles illustrated),
A path having a large power level is not always selected.

In the present embodiment, by making the antennas 11 to 14 movable, the paths are always reproduced in the order of higher power level (in this embodiment, the upper 12 paths). Specifically, in the present embodiment, first, the upper 12 paths of the power level are selected, and these 12 paths are assigned to three paths, which are the number of paths radiable from each antenna. For example, based on the path data in FIG. 2,
There are three ways to assign, as shown in FIGS.

In this embodiment, the arrival angle error (total angle error between the arrival direction of the path and the installation position of the transmitting antenna) is determined from these three allocation methods (FIGS. 5 to 7).
Is selected. The transmitting antenna 11
The positions to are set at positions where the angle of arrival error obtained by the equation (4) is minimized within the range of the angle of arrival in the combination of the three radiated paths shown in the figure.

[0058]

(Equation 4)

Therefore, as a result of the calculation by the equation (3), FIG.
When the transmitting antennas are arranged as shown in (1) and each path is assigned, the angle of arrival error is minimized.

As described above, in the present embodiment, the paths are selected in descending order of power level, and thereafter, the position of the transmitting antenna from which the selected path radiates is set, so that the power reproduction ratio of the path is always optimized. Value. Thereby, the reproduction accuracy of the radio wave environment in the actual field can be greatly improved.

In the above embodiments, as an example, the number of antennas is four and the number of paths radiable from each antenna is three, but the number is not particularly limited. Also, in order to facilitate the processing of the path selection processing unit 7,
For example, a transmitting antenna may be installed in the direction of arrival of the path having the highest power level in each region. In this case, the above calculation in the path selection processing unit 7 can be deleted, and a path can be easily assigned to each transmission antenna.

[0062]

As described above, according to the present invention, a plurality of reproducible paths are selected based on the electric field strength, the direction of arrival, and the delay profile of each path in the actual field, so that the path arrival The error in the direction can be reduced.
This has the effect of improving the reproduction accuracy of the radio wave environment in the actual field.

According to the next invention, the arrival direction of the radio wave has an offset value so that the sum of the angular errors between the arrival direction of the path and the direction of the transmitting antenna installation position for radiating the path is minimized. The radio wave environment in the real field was reproduced in the state. As a result, there is an effect that the reproduction accuracy of the radio wave environment in the actual field can be greatly improved.

According to the next invention, an offset value is provided in the direction of arrival of the radio wave so that the ratio of the sum of the power levels of the reproduced paths to the sum of the power levels of all the paths is minimized. The radio wave environment in the real field was reproduced in the state. As a result, there is an effect that the reproduction accuracy of the radio wave environment in the actual field can be greatly improved.

According to the next invention, a threshold value that satisfies a predetermined criterion is set for the angle of arrival error, and a path that maximizes the power reproduction ratio at an offset angle at which the angle of arrival error is equal to or smaller than the threshold value is selected. . As a result, there is an effect that an optimal radio wave environment can be reproduced in terms of both the angle of arrival error and the power reproduction ratio.

According to the next invention, a threshold value that satisfies a certain criterion for the power reproduction ratio is provided, and a path that minimizes the arrival angle error at an offset angle at which the power reproduction ratio is equal to or larger than the threshold value is selected. . As a result, there is an effect that an optimal radio wave environment can be reproduced in terms of both the angle of arrival error and the power reproduction ratio.

According to the next invention, the paths are selected in descending order of the power level, and thereafter, the position of the transmitting antenna from which the selected path radiates is set, so that the power reproduction ratio of the path is always set to the optimum value. can do. As a result, there is an effect that the reproduction accuracy of the radio wave environment in the actual field can be further greatly improved.

According to the next invention, it is possible to simplify the calculation processing in the path selecting means and easily assign a path to each antenna.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a test apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating an arrival direction and an electric field strength of a path before an offset.

FIG. 3 is a diagram showing the arrival direction and electric field strength of a path after offset.

FIG. 4 is a diagram showing a configuration of a test apparatus according to a third embodiment of the present invention.

FIG. 5 is a diagram illustrating an example of how to allocate paths.

FIG. 6 is a diagram illustrating an example of how to allocate paths.

FIG. 7 is a diagram illustrating an example of a path assignment method.

FIG. 8 is a diagram showing a configuration of a conventional test apparatus.

FIG. 9 is a diagram illustrating an example of an antenna arrangement of a conventional test apparatus.

FIG. 10 is a diagram showing the electric field strength and the arrival direction of a path.

FIG. 11 is a diagram showing a space around a reception position divided by the number of antennas.

FIG. 12 is a diagram illustrating a specific example of a delay profile.

FIG. 13 is a diagram illustrating a specific example of a delay profile.

[Explanation of symbols]

1 wireless terminal, 2 anechoic chamber, 3, 4 pseudo line, 5
Simulator, 6 path data storage unit, 7 path selection processing unit, 8 pseudo line control unit, 11, 12, 13, 14,
Receiving antenna, 21 Receiving antenna.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2G024 AD34 BA11 BA17 BA18 CA30 EA20 5K042 AA06 CA00 CA02 CA13 CA17 CA23 DA01 EA13 FA11 FA15 5K067 AA02 AA33 EE02 HH23 KK03 LL08

Claims (7)

[Claims] 1. A test apparatus for a radio terminal and a base station that reproduces a radio wave environment in a real field in an anechoic chamber in which a plurality of antennas are arranged. Parameter storage means for storing the direction of arrival and a path selection means for selecting a plurality of paths capable of reproducing the radio wave environment based on the parameters, and output from a simulator operating as a pseudo base station around the wireless terminal under test. Signal to be assigned to each transmission path according to the selected path, and further, transmission path control means for performing control for outputting a signal on the transmission path from the plurality of antennas, Test equipment. 2. The method according to claim 1, wherein the path selection unit selects a predetermined number of paths for each antenna unit such that the sum of angular errors between the arrival direction of the path to be reproduced and a fixed antenna installation position is minimized. The test device according to claim 1, wherein 3. The apparatus according to claim 2, wherein said path selection means selects a predetermined number of paths for each antenna unit such that the total sum of the electric field strengths of the paths reproduced by the fixed antenna installation positions is maximized. Item 2. The test apparatus according to Item 1. 4. The path selection means sets a fixed threshold value to a sum of angular errors between an arrival direction of a path to be reproduced and a fixed antenna installation position. 2. The test apparatus according to claim 1, wherein a predetermined number of paths are selected for each antenna unit such that the total sum of the electric field strengths of the paths reproduced at each antenna installation position is maximized. 5. The path selecting means sets a fixed threshold value for the sum of the electric field strengths of the paths reproduced by the fixed antenna installation positions, and is equal to or larger than the threshold value and the arrival direction of the reproduced path. The test apparatus according to claim 1, wherein a predetermined number of paths are selected for each antenna unit such that the total sum of angular errors between the antenna and a fixed antenna installation position is minimized. 6. The path selection means selects in advance a predetermined number of paths from the paths in the real field in descending order of electric field strength, and then determines the arrival direction of the selected path and each movable antenna. The test apparatus according to claim 1, wherein each antenna is installed so that the total of the angle errors is minimized. 7. The path selecting means pre-selects a predetermined number of paths in descending order of electric field strength from among the paths in the real field, and arrives at the path of the maximum electric field strength in the area of each antenna. The test apparatus according to claim 1, wherein each antenna is installed in the test apparatus.