CN111865371B

CN111865371B - MIMO testing device for multi-antenna wireless equipment

Info

Publication number: CN111865371B
Application number: CN201910354541.7A
Authority: CN
Inventors: 漆一宏; 于伟
Original assignee: GENERAL TEST SYSTEMS Inc
Current assignee: GENERAL TEST SYSTEMS Inc
Priority date: 2019-04-29
Filing date: 2019-04-29
Publication date: 2021-11-09
Anticipated expiration: 2039-04-29
Also published as: CN111865371A; WO2020220879A1

Abstract

The invention discloses a MIMO testing device of multi-antenna wireless equipment, which comprises: the wave absorbing material is arranged on the inner wall of the darkroom; the coupling probes are movably arranged in the darkroom and used for simultaneously or independently carrying out energy coupling transmission on the antenna in the preset near-field radiation range of the current probe position, wherein the maximum size of metal in all cross sections from the top of each coupling probe to the feeder within 5 centimeters is smaller than or equal to 5 centimeters, so that the MIMO throughput rate of the multi-antenna wireless device is obtained. According to the testing device provided by the embodiment of the invention, the virtual wire can be realized by adopting a single near-field coupling mode for the antenna, and the throughput rate of the antenna can be tested simultaneously or independently within a near-field radiation distance, so that the working efficiency of the test is improved, and the accuracy of the test is effectively improved.

Description

MIMO testing device for multi-antenna wireless equipment

Technical Field

The invention relates to the technical field of wireless equipment performance, in particular to a multi-antenna wireless equipment MIMO testing device.

Background

At present, the multi-antenna technology is one of the main means for increasing channel capacity, and especially, the multi-antenna MIMO (Multiple Input and Multiple Output) technology is used in 4G and 5G communication technologies, WiFi, internet of things, and the like to increase communication rate.

The MIMO measurement and evaluation of the antenna apparatus all play a crucial role in network quality, internet interference, base station layout, autonomous driving, etc. However, the present testing method and apparatus for specifying MIMO of antenna equipment by a series of standards promulgated by international standard 3GPP and national standard CCSA are generally large and expensive because far field testing or central field testing is used.

Specifically, there are two methods for MIMO throughput testing, the radiated two-step method (RTS) and the multi-probe Method (MPAC). The multi-probe method is used for testing by forming a channel model for MIMO throughput rate test by surrounding a plurality of antennas around the tested equipment, but system calibration and operation are complex, so that the multi-probe method is used for testing hardware with test precisionThe individual environment and the operation technique have higher requirements; firstly, a radiation two-step method measures a radiation directional diagram of a to-be-tested object (DUT) by utilizing a reporting function of a terminal in a darkroom, then directional diagram information is loaded into a channel simulator to simulate a wireless channel containing the antenna characteristic of the to-be-tested object, then a downlink signal output by a base station simulator is firstly convoluted with the wireless channel loaded with the directional diagram information of the to-be-tested object, the downlink signal is emitted by a measuring antenna, and finally performance test of a receiver is carried out, but both a multi-probe method and the radiation two-step method need to be carried out under a far-field condition, and the test distance is more than 2D²And lambda is high in test system cost and needs to be solved urgently.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, the invention aims to provide a multi-antenna wireless equipment MIMO testing device which can improve the working efficiency of testing and the accuracy of testing and is simple and easy to realize.

In order to achieve the above object, an embodiment of the present invention provides a multi-antenna wireless device MIMO testing apparatus, including: the wave absorbing material is arranged on the inner wall of the darkroom; the coupling probes are movably arranged in the darkroom and used for simultaneously or independently performing energy coupling transmission on the antenna in a preset near-field radiation range of the current probe position, wherein the maximum size of metal in all cross sections of the top of each coupling probe, within 5cm from the top of the probe, towards the feeder line is less than or equal to 5cm, so that the MIMO throughput rate of the multi-antenna wireless device is obtained.

The air interface testing device of the multi-antenna wireless equipment of the embodiment of the invention simultaneously tests each antenna of the wireless equipment through the plurality of coupling probes, thereby realizing the purpose that the multi-antenna simultaneously or independently tests the near-field radiation distance, not only realizing the virtual wire by adopting an independent near-field coupling mode for the antenna, but also simultaneously testing the MIMO throughput rate of the plurality of antennas, further effectively improving the working efficiency of the test, effectively improving the accuracy of the test, and being simple and easy to realize.

In addition, the air interface testing apparatus for a multi-antenna wireless device according to the above embodiment of the present invention may further have the following additional technical features:

further, in one embodiment of the present invention, the position and orientation of each coupling probe of the plurality of coupling probes satisfy a preset channel isolation degree.

Further, in an embodiment of the present invention, the method further includes: the test instrument is connected with the coupling probes and comprises a channel simulator, so that a throughput rate test signal is obtained by using the channel simulator in combination with a channel model and antenna directional pattern information of the multi-antenna wireless equipment, and the MIMO throughput rate is obtained.

Optionally, in an embodiment of the present invention, the preset near-field radiation range is obtained according to the following formula:

or

Wherein D is the maximum physical size of the multi-antenna wireless device, R is the radius of the near-field radiation range, and λ is the wavelength.

Optionally, in an embodiment of the present invention, a maximum dimension of the metal in all cross-sections of the probe tip of each coupling probe within 5cm of the feeder is smaller than a maximum physical dimension of the multi-antenna wireless device.

Optionally, in an embodiment of the present invention, the maximum size of the metal in all cross sections of the probe top of each coupling probe within 5cm from the feeder line is smaller than the maximum physical size of the corresponding antenna.

In an embodiment of the present invention, when the multi-antenna wireless device is a mobile terminal, the coupling probe is a broadband probe with a preset bandwidth.

Further, in an embodiment of the present invention, the method further includes: a placement component for placing the multi-antenna wireless device; the vertical position adjusting piece is connected with the placing assembly to adjust the vertical height of the placing assembly.

Further, in an embodiment of the present invention, the method further includes: and each moving assembly of the plurality of moving assemblies is respectively connected with each coupling probe of the plurality of coupling probes so as to change the position of the corresponding coupling probe.

Further, in an embodiment of the present invention, the method further includes: the first control assembly is connected with the vertical position adjusting piece and the placing assembly so as to control the vertical position adjusting piece and the placing assembly to execute corresponding actions, so that the multi-antenna wireless device reaches a target position; a second control component connected to each of the moving components, respectively, to adjust a position and a direction of each of the plurality of coupling probes according to the target position of the multi-antenna wireless device.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a diagram illustrating a multipath environment from a base station to a terminal in the related art;

fig. 2 is a diagram illustrating a multi-path channel model implemented by an MPAC through a multi-antenna configuration in the related art;

FIG. 3 is a schematic view illustrating a principle of a related art radiation two-step method;

FIG. 4 is a schematic view of a propagation environment inside a darkroom in the related art;

FIG. 5 is a diagram illustrating a join matrix module according to the related art;

FIG. 6 is a schematic block diagram of a dummy conductor in the related art;

FIG. 7 is a schematic structural diagram of a MIMO testing apparatus for multi-antenna wireless devices according to an embodiment of the present invention;

FIG. 8 is a schematic structural diagram of a coupling probe according to one embodiment of the present invention;

fig. 9 is a schematic structural diagram of a related art multi-antenna wireless device;

FIG. 10 is a schematic diagram of a multi-antenna wireless device MIMO test apparatus according to one embodiment of the present invention;

fig. 11 is a schematic directional diagram of a multi-antenna wireless device in accordance with one embodiment of the present invention;

fig. 12 is a schematic directional diagram of a multiple antenna wireless device in accordance with another embodiment of the present invention;

fig. 13 is a schematic structural diagram of a MIMO testing apparatus for a multi-antenna wireless device according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

Before describing the phased array antenna protocol testing apparatus proposed according to the embodiment of the present invention, the following briefly describes the drawbacks of the existing far field testing technology.

In the prior art, there are two methods for MIMO throughput testing, including the radiative two-step method (RTS) and the multi-probe Method (MPAC). It should be noted that the wireless performance of the MIMO terminal depends on a plurality of factors: terminal own receiver sensitivity, noise, transmitter power, antenna correlation, antenna and receiver transmitter matching, baseband processing, wireless propagation environment, etc. An OTA (Over The Air) test scheme of an MIMO terminal provides a method and a test system for evaluating and testing The performance of The MIMO terminal in a controlled environment. The OTA test of the MIMO terminal is not only the basis for a mobile operator to check the performance of the mobile terminal and issue the network access license of the terminal, but also the technical means of a terminal manufacturer in the processes of research, development and quality control. The OTA test is also a test means that is recognized by the current international organization for standardization 3GPP (3rd Generation Partnership Project) and the national organization for standardization CCSA (China Communications Standards Association) to be capable of evaluating the true wireless performance of the MIMO wireless terminal.

Specifically, for the reception performance (i.e., downlink MIMO performance) of the MIMO wireless terminal, the 3GPP provides two standard OTA test schemes: MPAC (Multiple Probe analogue Chamber method) and RTS (radial Two Stage method). And the most critical index for evaluating the downlink MIMO performance is throughput rate. MIMO utilizes diversity techniques to increase the communication rate, where the electromagnetic wave spatial propagation environment (i.e., channel model) is an important factor in determining its throughput. As shown in fig. 1, fig. 1 shows a multipath environment in which a wireless MIMO terminal is located. Including direct-view paths from the base station to the terminal, individual building transmit paths, and doppler effects, among others.

In particular, the mimo ota test requires modeling a prescribed channel model and then testing the magnitude of its throughput under the model. The MPAC method, which uses a plurality of antennas (e.g. 16) surrounding the tested piece together with a channel simulator to realize the simulation of MIMO channel, is an intuitive method, but the system cost is very high and the system calibration is complicated, as shown in fig. 2.

In addition, as shown in fig. 3 to fig. 6, in the radiation two-step method, the directional diagram of the receiving antenna of the tested device is obtained in the first step, the throughput rate test signal is generated in the second step by combining the obtained receiving directional diagram with the channel model, and then the throughput rate test signal is fed into the corresponding receiver in a radiation manner, so as to perform the throughput rate test. In the two-step radiation method, one key technology is loading an inverse matrix and establishing a virtual wire technology link. The method comprises the following specific steps: after the antenna directional pattern is obtained by the radiation two-step method, the antenna directional pattern and the channel model are combined in the instrument for operation to obtain a multi-channel throughput rate test signal. Each path's throughput test signal requires a separate isolated input to the corresponding receiver. Here, a technique of "dummy wires" is employed in a plurality of places. Specifically, as shown in fig. 4, a multi-antenna device under test is placed in a shielded room, where the number M of test antennas is equal to the number N of antennas of the device under test, and then electromagnetic waves are emitted from the N test antennas to the N receiving antenna feed points to form a stable propagation matrix, which is recorded as a propagation matrix P, where P is an N × N matrix.

Specifically, a radio frequency matrix module is added to the front end of the test antenna, and as shown in fig. 5, the value of the radio frequency matrix module V is set to be equal to the inverse of the propagation matrix P. I.e. P ═ V^-1Signals (T) of N test ports₁,T₂,…,T_N) Received signals (R) with N receiver ports₁,R₂,…,R_N) Satisfy the relationship

(R₁,R₂,…,R_N)^T＝P*V*(T₁,T₂,…,T_N)^T＝(T₁,T₂,…,T_N)^T

( )^TRepresenting a matrix transposition.

The above formula shows that, under such a configuration, the signal at the test port can be directly introduced into the receiver port, similar to the manner of conducting wire access, with the difference that: the tested piece is always in the state of the whole machine without any intrusive wire connection, and the performance obtained by testing is the real working performance of the tested piece. Such a mode of operation is also referred to as a "virtual wire" technique, with N virtual wires connecting the test port and the receiver port as shown below. In fig. 4, 5, and 6, when N is 2, the implementation mode of fig. 3 is obtained.

However, currently, both MPAC and RTS need to be performed in far-field conditions, i.e. testing distances greater than 2D²And/λ, D is the maximum physical dimension of the measured piece.

A multi-antenna wireless device MIMO test apparatus proposed according to an embodiment of the present invention is described below with reference to the accompanying drawings.

Fig. 7 is a schematic structural diagram of a MIMO testing apparatus for a multi-antenna wireless device according to an embodiment of the present invention.

As shown in fig. 7, the multi-antenna wireless device MIMO test apparatus 10 includes: a darkroom 100 and a plurality of coupling probes (shown as coupling probe 201, coupling probe 202, coupling probe 203, and coupling probe 204).

Wherein, the inner wall of the darkroom 100 is provided with a wave-absorbing material 101. The plurality of coupling probes are movably arranged in the darkroom 100 and used for simultaneously or independently performing energy coupling transmission on the antenna in the preset near-field radiation range of the current probe position, wherein the maximum size of metal in all cross sections within 5 centimeters from the top of each coupling probe to the feeder line is less than or equal to 5 centimeters, so that the MIMO throughput rate of the multi-antenna wireless device is obtained. It can be understood that each coupling probe of the plurality of coupling probes can be movably disposed in a one-to-one correspondence manner in a preset near-field radiation distance of a plurality of antennas of the multi-antenna wireless device 20, and simultaneously, energy coupling transmission is performed on the multi-antenna wireless device 20 to be tested, so as to obtain the MIMO throughput of the multi-antenna wireless device 20. The testing device 10 of the embodiment of the invention can realize the virtual wire by adopting a single near-field coupling mode for the antenna, and can simultaneously or independently test the throughput rate of the antenna in the near-field radiation distance, thereby not only improving the working efficiency of the test, but also effectively improving the accuracy of the test.

Specifically, the testing apparatus according to the embodiment of the present invention may perform a wireless performance test on the coupled MIMO wireless device, so as to achieve an overall performance evaluation of the MIMO wireless device (for example, a tested device working in MIMO multi-path code streams), and a performance of each individual radio frequency path of the MIMO wireless device (for example, consistency of transmission power of each individual path, and a receiving radiation sensitivity of each individual path).

It should be noted that, compared with the related art, the embodiment of the present invention may implement one-to-one corresponding coupling transmission, and also implement a "virtual wire" technology applied in a standard radiation two-step method, where the difference is that the embodiment of the present invention implements a "virtual wire" by a coupling method, and the radiation two-step method implements a "virtual wire" by a calculation method, so that after implementing a virtual wire, the embodiment of the present invention may perform a throughput rate test.

Specifically, as shown in fig. 8, it can be understood that the portion of the coupling probe within 5cm from the radiating top toward the feeder line direction satisfies: the maximum dimension of the metal of all cross sections is less than or equal to 5 cm. For example, a coupling probe consists of three parts: the coupling probe comprises a medium, a metal and a feeder line, wherein the feeder line is used for feeding radio frequency signals, the top of the coupling probe is a radiation top end, and any cross section meets the following conditions within a range from the top of the coupling probe to 5cm of the feeder line: the maximum dimension of the metal in all cross sections from the top to the 5cm of the feed line is less than 5cm, and it will be understood by those skilled in the art that any probe in fig. 8 can be configured in a similar manner, and is not limited to an antenna design of this structure, as long as the maximum dimension of the metal in the cross section is less than 5cm, so as to simultaneously or separately perform energy coupling transmission on the antenna within the near-field radiation distance of the current probe.

For example, as shown in fig. 9, which is a schematic diagram of a complete 4-antenna wireless terminal to simulate a multi-antenna wireless device 20 to be tested, a PIFA antenna is placed at each of four corners of a 140 × 70mm PCB, and the four antennas are connected to the same ground, and the antennas operate at 3.5 GHz.

In the embodiment of the present invention, the multi-antenna wireless device 20 is placed in a shielding dark room 100, a wave-absorbing material 101 is placed in the dark room 100, and a plurality of coupling probes are placed in the dark room 100. The probe has the effects that each probe aims at one antenna on the multi-antenna wireless device 20 to perform energy coupling transmission, it needs to be noted that the coupling probes are all located in the near-field radiation distance of the multi-antenna wireless device 20, the positions and directions of the coupling antennas can be adjusted to enable each coupling antenna and the corresponding tested antenna to form one-to-one coupling transmission, and the separate coupling mode is adopted through different antennas, so that the cost of a test system can be reduced, the test time is effectively reduced, and the test efficiency is improved.

Compared with the far field test in the related technology, the embodiment of the invention can realize the fast production line test of the multi-antenna wireless terminal, has higher test working efficiency, can effectively ensure the accuracy and precision of the test and effectively meet the test requirement.

Further, in one embodiment of the present invention, the position and orientation of each coupling probe of the plurality of coupling probes satisfy a preset channel isolation. .

Specifically, as shown in fig. 10, the antenna names are as shown, and the antennas of the multi-antenna wireless device 20 may name the

antennas

1, 2, 3, 4 under test; the coupling probes may be named

coupling probes

5, 6, 7, 8.

Firstly, adjusting the positions of all coupling probes to enable the physical positions of the coupling probes to be positioned in the near field of the multi-antenna wireless equipment 20 and close to the corresponding antenna positions, for example, the antenna 1 to be measured corresponds to the coupling antenna 5; the tested antenna 2 corresponds to the coupling antenna 6; the antenna to be measured 3 corresponds to the coupling antenna 7; the antenna under test 4 corresponds to the coupling antenna 8. Wherein, the coupling energy between the corresponding antennas is required to be larger than the coupling energy between the non-corresponding antennas, and the specific expression is as follows:

fixing the measured piece, taking the position adjustment of the coupling antenna 5 as an example: adjusting the position of the No. 5 coupling antenna to enable only the No. 5 coupling antenna to transmit, wherein the coupling energy on the No. 1 antenna to be tested is greater than the energy coupled to all other antennas to be tested; similarly, the position of the No. 6 coupling antenna is adjusted, so that only the No. 6 coupling antenna transmits, and the coupling energy on the No. 2 antenna to be tested is greater than the energy coupled to all other antennas to be tested; adjusting the position of the No. 7 coupling antenna to enable only the No. 7 coupling antenna to transmit, wherein the coupling energy on the No. 3 antenna to be tested is greater than the energy coupled to all other antennas to be tested; and adjusting the position of the No. 8 coupling antenna to enable only the No. 8 coupling antenna to transmit, wherein the coupling energy on the No. 4 antenna to be tested is larger than the energy coupled to all other antennas to be tested.

It should be noted that, defining the corresponding channel and the non-corresponding channel may be as follows:

no. 1 corresponds to No. 5, No. 2 corresponds to No. 6, No. 3 corresponds to No. 7, No. 4 corresponds to No. 8, No. 1 corresponds to No. 5 and is defined as a corresponding channel, 1-6, 1-7 and 1-8 are non-corresponding channels, and the channel gain is represented by G, so that the corresponding channel isolation is defined as (3 isolation in total):

Iso_{1_5|1_6}＝G_{1_5}-G_{1_6}，

Iso_{1_5|1_7}＝G_{1_5}-G_{1_7}，

Iso_{1_5|1_8}＝G_{1_5}-G_{1_8}，

wherein, Iso_x|yIs the degree of separation of the x-corresponding channel relative to the y-non-corresponding channel; g_iIs the i-channel gain (dB format). And 2-6 corresponding channel isolation degrees can be obtained by the same method:

Iso_{2_6|2_5}＝G_{2_6}-G_{2_5}，

Iso_{2_6|2_7}＝G_{2_6}-G_{2_7}，

Iso_{2_6|2_8}＝G_{2_6}-G_{2_8}，

and 3-7 corresponding channel isolation degrees can be obtained by the same method:

Iso_{3_7|3_5}＝G_{3_7}-G_{3_5}，

Iso_{3_7|3_6}＝G_{3_7}-G_{3_6}，

Iso_{3_7|3_8}＝G_{3_7}-G_{3_8}，

and 4-8 corresponding channel isolation degrees can be obtained by the same method:

Iso_{4_8|4_5}＝G_{4_8}-G_{4_5}，

Iso_{4_8|4_6}＝G_{4_8}-G_{4_6}，

Iso_{4_8|4_7}＝G_{4_8}-G_{4_7}，

the position, direction, etc. of the detecting antenna can be adjusted manually or automatically by the control component according to the information of the detected piece, i.e. the multi-antenna wireless device 20, so that the isolation information of each corresponding channel can be improved.

It should be noted that, in the embodiment of the present invention, the testing accuracy can be guaranteed only when the isolation degrees of the corresponding channels all satisfy a certain condition, for example, when the isolation degrees of all the corresponding channels are greater than 5dB, the influence on the testing accuracy of the MIMO throughput is less than 1dB (estimated value), and when the isolation degrees of all the corresponding channels are greater than 10dB, the influence on the testing accuracy of the MIMO throughput is less than 0.2dB (estimated value).

Theoretically, when the coupling probe approaches the measured piece, the corresponding channel isolation degree can be correspondingly improved. Generally, the greater the isolation that is desired during testing, the better, but in practice, another condition needs to be considered: generally, as for the tested object, when testing performance, it is necessary to cause as little interference as possible to the tested object itself, and as for fig. 3, when the distance between the probe 5 and the antenna 1 of the tested object changes, the antenna of the tested object may be interfered by the probe to itself, so that its radiation characteristic changes (which may be referred to as causing loading to the tested object).

The following is a detailed description of a specific embodiment.

As shown in fig. 11, the directional pattern of the antenna 1 of the tested object is compared with the probe loading or not at 5mm, wherein the dotted line indicates the probe loading, and the solid line indicates the probe loading or not. Further, as shown in fig. 12, the directional pattern of the antenna 1 of the tested object is compared with the probe loading or not at 15mm, wherein the dotted line indicates the probe loading, and the solid line indicates the probe loading or not.

In conclusion, it can be seen that the probe is arranged at 15mm, the antenna of the tested piece is not affected basically (the radiation pattern is not changed basically), and the isolation of all corresponding channels is more than 10dB at 15mm, so that the accurate MIMO throughput rate test can be performed.

However, even if the coupling probe is loaded at 5mm, the influence on the tested piece is only the influence on the test precision, but the influence on the throughput test caused by the loading on the tested piece is not well evaluated. Therefore, in general, in embodiments of the present invention, the coupling probe antenna does not contact the radiating element of the dut.

The throughput rate test is carried out after the relative positions of the coupling probe and the tested piece are determined, and the step only needs to be carried out once for a product (or similar products), so that the position of the coupling probe, which accords with the test antenna, can be found.

Further, in an embodiment of the present invention, the testing apparatus 10 of the embodiment of the present invention further includes: the meter 300 is tested. The test meter 300 is connected to a plurality of coupling probes and the test meter 300 comprises a channel simulator to obtain a throughput test signal using the channel simulator in combination with the channel model and the antenna pattern information of the multi-antenna wireless device 20 to obtain the MIMO throughput.

For example, antenna pattern information (which may be preset, simulated, or obtained through testing) of the multi-antenna wireless device 20 is obtained, so that a throughput rate test signal is obtained by using a channel simulator in combination with the channel model and the antenna pattern information of the device under test, and after a corresponding channel gain is compensated, the throughput rate test signal is fed into the coupling probe to test the throughput rate performance of the device under test.

Specifically, taking a 4 × 4 MIMO throughput test as an example, the test procedure may be as follows:

step S1: acquiring antenna directional pattern information (which can be preset and simulated) of a tested piece;

step S2: and using a channel simulator to obtain a throughput rate test signal by combining the channel model and the antenna directional pattern information of the tested piece, and feeding the throughput rate test signal into the detection antenna after compensating corresponding channel gains for each channel, thereby testing the throughput rate performance of the tested piece.

Alternatively, in an embodiment of the present invention, the preset near-field radiation range may be obtained according to the following formula:

or

Where D is the maximum physical size of the multi-antenna wireless device, λ represents the wavelength, R is the radius of the near-field radiation range, i.e., R is the near-field radiation distance, and λ is the wavelength.

In the embodiment of the present invention, the near-field radiation test implemented on the tested piece in the embodiment of the present invention is substantially different from the far-field test in the related art, and the near-field radiation test is described in detail below:

for example, the antenna distance of the coupling probe and the multi-antenna wireless device 20 of the embodiment of the present invention is smaller than the far field, and is in near-field coupling, specifically, for the small-sized antenna to be tested (the physical size is smaller than half of the wavelength), the distance from the position of the antenna to be tested R is defined as:

belongs to a reactive near field (reactive near field), wherein lambda represents wavelength;

belonging to the radiation near-field region (radial near-field);

λ < R ≦ 2 λ belongs to the transmission near field region (transition zone);

2 lambda < R belongs to the radiation far field region.

Aiming at the tested piece, the distance between the coupling probe and the antenna of the tested piece is smaller than the far field condition, and the antenna is in a reaction near field region

For the measured antenna with electric size (the physical size is more than or equal to half of the wavelength), the distance from the measured antenna R is defined as,

belonging to a radiation near field region, wherein D is the size of the antenna to be measured;

belongs to a Fresnel zone;

belonging to the radiation far-field region

For the tested piece, the distance between the coupling probe and the antenna of the tested piece is smaller than the far-field condition, and the coupling probe is in a radiation near-field region.

In summary, the testing apparatus 10 of the embodiment of the present invention can not only make each coupling probe correspond to one tested antenna, so as to obtain each antenna information of the multi-antenna wireless device 20 quickly, and even perform testing simultaneously, but also have smaller testing path loss compared with the related art, each tested antenna has one coupling antenna close to and corresponding to the tested antenna, and belongs to near field coupling, and the path loss is far smaller than that of the testing systems in all schemes in the related art, so that the testing dynamic is large.

Optionally, in an embodiment of the invention, the maximum dimension of the metal in all cross-sections of the probe tip of each coupling probe within 5cm of the feeder is smaller than the maximum physical dimension of the multi-antenna wireless device, and/or the maximum dimension of the metal in all cross-sections of the probe tip of each coupling probe within 5cm of the feeder is smaller than the maximum physical dimension of the corresponding antenna.

It is to be appreciated that in embodiments of the present invention, the coupling probe size (without feeder) antenna aperture is smaller than the maximum physical size of the multi-antenna wireless device 20 and/or the coupling probe size (without feeder) antenna aperture is smaller than the maximum physical size of its corresponding antenna under test on the multi-antenna wireless device 20. Thereby ensuring the accuracy of the test.

In an embodiment of the present invention, when the multi-antenna wireless device is a mobile terminal, the coupling probe is a broadband probe with a preset bandwidth, for example, a probe covering all sub6G frequency bands can be used.

For example, in sub6G, when the mobile phone is used as a tested piece, at least 4 coupling probes are respectively located at 4 corners of the tested piece, and the coupling probes can be broadband probes, so that when the test frequency is changed, other antennas do not need to be switched, the simultaneous test of the transceiving performance of the multiple antennas can be realized, the test working efficiency is greatly improved, and the test time is reduced. Wherein, the preset bandwidth can be set by those skilled in the art according to actual situations.

Further, in an embodiment of the present invention, as shown in fig. 13, the testing apparatus 10 of the embodiment of the present invention further includes: and placing the component. Wherein the placement component is used to place the multi-antenna wireless device 20.

It is understood that a placement assembly, such as a placement table provided with clamps, may be provided in the darkroom 100 to place the multi-antenna wireless device 20 on the placement assembly to facilitate testing of the multi-antenna wireless device 20. In addition, the placing assembly can also adjust the horizontal pose of the wireless setting 20, for example, the wireless setting 20 is controlled to change the pose clockwise, so as to meet the testing requirement.

Further, in an embodiment of the present invention, the testing apparatus 10 of the embodiment of the present invention further includes: a plurality of moving assemblies. Wherein each moving assembly of the plurality of moving assemblies is respectively connected with each coupling probe of the plurality of coupling probes so as to change the position of the corresponding coupling probe.

It is understood that the moving component can be a moving table provided with a roller to arbitrarily adjust the position of the coupling probe to achieve the corresponding arrangement with the antenna of the tested piece.

Further, in an embodiment of the present invention, the testing apparatus 10 of the embodiment of the present invention further includes: a vertical position adjusting member. Wherein, vertical position adjustment spare links to each other with placing the subassembly to the vertical height of adjustment placing the subassembly.

It can be understood that, a vertical position adjusting member is disposed at the bottom end of the darkroom, for example, two supports are disposed at a relative interval, each support may include two hinged rod bodies, the lower end of each rod body is rotatably fitted to the bottom end of the darkroom, and the upper end of each rod body is movably fitted to the placing table, so that the placing posture of the multi-antenna wireless device 20 can be adjusted by adjusting the vertical height of the placing assembly relative to the bottom end of the darkroom, so as to adjust the placing posture according to the testing requirements, for example, the multi-antenna wireless device 20 is disposed at the center of the darkroom 100.

In the embodiment of the present invention, the placement member and the placement member may be movably disposed by the vertical position adjustment member, so that the antenna wireless device 20 may be conveniently adjusted in the horizontal direction and/or the vertical direction, and the flexibility and the applicability of the apparatus are improved.

Further, in an embodiment of the present invention, the testing apparatus 10 of the embodiment of the present invention further includes: a first control assembly. Wherein the first control assembly is connected to the vertical position adjustment assembly and the placement assembly to control the vertical position adjustment assembly and the placement assembly to perform corresponding actions so that the multi-antenna wireless device 20 reaches the target position.

It is understood that the vertical position adjustment and placement assembly can be controlled manually or automatically by a predetermined program, such as automatically raising and rotating the multi-antenna wireless device 20 to a testing position, i.e., a target position, required by the test to meet the testing requirements.

Further, in an embodiment of the present invention, the testing apparatus 10 of the embodiment of the present invention further includes: a second control assembly. Wherein the second control assembly is connected to each of the moving assemblies, respectively, to adjust the position and orientation of each of the plurality of coupled probes based on the target position of the multi-antenna wireless device 20.

It can be understood that the testing apparatus 10 according to the embodiment of the present invention can be adjusted manually or automatically by the control component, so as to improve the intelligence and controllability of the testing apparatus. Specifically, the measured part is placed on the placing component, the coupling probes are placed on the moving component, each coupling probe is connected with one moving component and can move independently, the placing component can lift, and then the one-to-one correspondence setting of the coupling probes and the antennas is realized, so that the measuring device is more flexible and is simple and easy to realize.

For example, after the tested object is fixed by the placing assembly, the operator may move the tested object to the midpoint position of the darkroom 100 by controlling the placing assembly and the vertical position adjusting assembly through the manual adjusting or controlling assembly, and then move the coupling probe to the corresponding position of each antenna of the tested object by controlling the moving assembly through the manual adjusting or controlling assembly, so as to perform the near-field coupling antenna test within the near-field radiation distance.

In summary, in the embodiment of the present invention, the test scheme is fast, each coupling probe corresponds to one tested antenna, and information of each antenna of the tested device can be obtained quickly, so that information of a plurality of tested antennas can be obtained all at one time, the test speed is much faster than that of the related art, and compared with the related art, the present invention has smaller test path loss, each tested antenna has one coupling antenna close to and corresponding to the antenna, and belongs to near-field coupling, and the path loss is much smaller than that of all test systems in the related art, so the test dynamic is large.

According to the MIMO testing device of the multi-antenna wireless equipment, the throughput rate of each antenna of the wireless equipment is tested simultaneously or independently through the plurality of coupling probes, the testing requirement is effectively met, the aim of simultaneously testing the plurality of antennas can be fulfilled, the antennas can be in an independent near-field coupling mode, namely, virtual wires can be realized by adopting independent coupling modes for different antennas, the plurality of antennas can be tested simultaneously, the distance between the coupling probes and the tested piece antenna belongs to the near-field radiation distance which is smaller than the far-field distance and is in near-field coupling, the testing working efficiency is effectively improved, the testing accuracy is effectively improved, and the testing is simple and easy to realize.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.

Claims

1. A multi-antenna wireless device MIMO testing apparatus, comprising:

the wave absorbing material is arranged on the inner wall of the darkroom;

the coupling probes are movably arranged in the darkroom and used for simultaneously or independently carrying out energy coupling transmission on the antenna to be measured in a preset near-field radiation range of the current probe position, wherein the maximum size of metal in all cross sections from the top of each coupling probe to the feeder line within 5cm is less than or equal to 5cm, each coupling probe corresponds to one antenna to be measured, the testing device is used for adjusting the position and the direction of the coupling probes so that the coupling energy between each coupling probe and the corresponding antenna under test is larger than the coupling energy between the non-corresponding antenna under test, and enabling each coupling probe and the corresponding antenna to be tested to form one-to-one coupling transmission to form a virtual wire so as to obtain the MIMO throughput rate of the multi-antenna wireless equipment.

2. The apparatus of claim 1, wherein the position and orientation of each coupling probe of the plurality of coupling probes satisfies a predetermined corresponding channel isolation.

3. The apparatus of claim 2, wherein the corresponding channel isolation is a difference between a channel gain of a corresponding channel and a channel gain of a non-corresponding channel, wherein the corresponding channel is a channel between the coupling probe and the corresponding antenna under test, and the non-corresponding channel is a channel between the coupling probe and the other antenna under test.

4. The apparatus of claim 3, wherein the corresponding channel isolation is greater than 5 dB.

5. The apparatus of claim 1, further comprising:

the test instrument is connected with the coupling probes and comprises a channel simulator, so that a throughput rate test signal is obtained by using the channel simulator in combination with a channel model and antenna directional pattern information of the multi-antenna wireless equipment, and the MIMO throughput rate is obtained.

6. The apparatus of claim 1, wherein the preset near-field radiation range is obtained according to the following formula:

or

7. The apparatus of claim 1, wherein the probe tip of each coupling probe is smaller than the maximum physical size of the multi-antenna wireless device within the maximum dimension of metal within all cross-sections of 5 centimeters into the feed line.

8. A device according to claim 1 or 7, wherein the maximum dimension of the metal in all cross-sections of the probe tip of each coupling probe within 5cm of the feedline is less than the maximum physical dimension of the corresponding antenna.

9. The apparatus of claim 1, further comprising:

a placement component for placing the multi-antenna wireless device;

the vertical position adjusting piece is connected with the placing assembly to adjust the vertical height of the placing assembly.

10. The apparatus of claim 9, further comprising:

and each moving assembly of the plurality of moving assemblies is respectively connected with each coupling probe of the plurality of coupling probes so as to change the position of the corresponding coupling probe.

11. The apparatus of claim 10, further comprising:

the first control assembly is connected with the vertical position adjusting piece and the placing assembly so as to control the vertical position adjusting piece and the placing assembly to execute corresponding actions, so that the multi-antenna wireless device reaches a target position;

a second control component connected to each of the moving components, respectively, to adjust a position and a direction of each of the plurality of coupling probes according to the target position of the multi-antenna wireless device.