Calibration method of multi-antenna test system and multi-antenna test system

Abstract

The present invention discloses a multi-antenna test system and a calibration method for the multi-antenna test system. The calibration method for the multi-antenna test system comprises: step S100, sequentially testing the transmission power of multiple first products to be tested placed in a test fixture in each frequency band on different transmission channels, and obtaining corresponding transmission power data; step S200, sequentially performing omnidirectional radiation power tests on multiple first products to be tested, and obtaining corresponding omnidirectional radiation power data; step S300, analyzing the obtained data; after adjusting the position and / or angle of the antenna module on each transmission channel, returning to execute step S100 until the antenna module that best matches the product to be tested among the multiple antenna modules is obtained; step S500, calibrating the line loss of each transmission channel of the test system; step S600, verifying the calibration of the test system to obtain the position and angle of each antenna module.

Description

Technical Field

[0001] The present invention relates to the field of antenna testing technology, and in particular to a calibration method for a multi-antenna testing system and a multi-antenna testing system. Background Art

[0002] With the rapid development and popularization of voice recognition, smart home, AR / VR and wearable products, more and more products integrate multiple wireless technology functions such as Bluetooth, Zigbee and WiFi, and even a single product integrates multiple WiFi or UWB antennas. In order to meet the performance index requirements of the whole product design, all products produced need to be calibrated or tested, but now smart products are often system-level, with many integrated antennas, which are usually tested separately. This kind of testing workload is large, and when the antennas are placed in the same test system for serial testing, it is difficult to simultaneously match the various antennas of the product to achieve stable testing, which makes the testing work complicated and difficult to carry out. Summary of the invention

[0003] The main purpose of the present invention is to provide a calibration method for a multi-antenna test system and a multi-antenna test system, aiming to improve the antenna test efficiency of smart products.

[0004] To achieve the above object, the present invention proposes a calibration method for a multi-antenna test system, wherein the multi-antenna test system comprises a test fixture, a comprehensive tester and a plurality of antenna modules, wherein the relative positions and angles between the plurality of antenna modules and the test fixture are different, and a plurality of transmission channels are formed between each product to be tested placed in the test fixture and the plurality of antenna modules and the comprehensive tester, and the calibration method for the multi-antenna test system comprises:

[0005] Step S100, sequentially testing the transmission power of multiple first products to be tested placed in the test fixture in each frequency band on different transmission channels, and obtaining corresponding transmission power data;

[0006] Step S200, performing omnidirectional radiation power tests on a plurality of first products to be tested in sequence, and obtaining corresponding omnidirectional radiation power data;

[0007] Step S300: performing a linear regression model analysis based on the least squares method on the acquired transmission power data and omnidirectional radiation power data;

[0008] Step S400: After adjusting the position and / or angle of the antenna module on each transmission channel, return to execute step S100 until an antenna module that best matches the product to be tested among the multiple antenna modules is obtained;

[0009] Step S500: Select a first preset number of calibration products and sequentially place them into a test fixture to calibrate the line loss of each transmission channel of the test system;

[0010] Step S600: Select a preset number of standard sample products to verify the calibration of the test system, and when the verification result meets the standard, record the position and angle of each antenna module.

[0011] Optionally, before step S100, the calibration method of the multi-antenna test system further includes:

[0012] Step S700: pre-calibrate the line loss of each transmission channel of the test system.

[0013] Optionally, the step S700 specifically includes:

[0014] Step S710, randomly selecting one of the multiple products to be tested as a temporary standard sample, and placing it in the test fixture, switching the selected multiple transmission channels in turn according to a preset order, and when each transmission channel is turned on, controlling the temporary standard sample to sequentially send excitation signals of multiple preset frequency bands to obtain the radio frequency signal received by the antenna module in the transmission channel;

[0015] Step S720: performing line loss analysis on the acquired radio frequency signals of the multiple channels to obtain compensated line loss data of each transmission channel;

[0016] Step S730: Compensate the compensated line loss data into the test system.

[0017] Optionally, the line loss data is calculated using the following formula:

[0018] Pathloss(f)(Chn)=Pre-Set(30dB)+(Target(dB)-(Tn(f))); f=2402MHz, 2441MHz, 2480MHz;

[0019] Or, Pathloss(f)(Chn)=Pre-Set(30dB)+(laboratory test value-(Tn(f)); f=2402MHz, 2441MHz, 2480MHz; where,

[0020] Pathloss(f)(Chn) is the line loss value when the nth transmission channel among the selected multiple transmission channels is turned on, Chn is the channel number, Pre-Set(30dB) is the preset line loss value, Target(dB) is the target line loss value, (Tn(f) is the actual line loss value when the nth transmission channel is turned on.

[0021] Optionally, the step S100 specifically includes:

[0022] Multiple products to be tested are placed in the test fixture in sequence, and the selected multiple transmission channels are switched on in turn according to the preset order. When each transmission channel is turned on, the products to be tested are controlled to send excitation signals of preset frequency bands in sequence according to the preset order to obtain the transmission power of the products to be tested in each frequency band on different channels.

[0023] Optionally, the step S300 specifically includes:

[0024] Establish a univariate linear regression model, specifically:

[0025] Y i =αX i +β+ε i , (i=1, 2, ..., n);

[0026] In the formula, αX i +β is a linear function, X i is the TRP test value; Y i For OTA test station T xP ower Test value, ε i are random errors, independent of each other;

[0027] The linear coefficient α and its estimated value in the univariate linear regression model are obtained from the transmission power data, isotropic radiated power data and their observed values The intercept β and its estimated value and the residual square σ 2 and its estimated value Get the estimated formula of the empirical equation:

[0028]

[0029] Construct the Q(xi,yi) function:

[0030]

[0031] Find the partial derivative of Q with respect to a and b;

[0032]

[0033] We get the system of equations:

[0034]

[0035] The solution is:

[0036]

[0037] Calculate the correlation coefficient R:

[0038]

[0039] in,

[0040] Optionally, the step S600 specifically includes:

[0041] Perform transmission power tests on a preset number of standard sample products, and obtain the transmission power test average value of multiple preset products;

[0042] Verification is performed based on a first difference between the test average value and the target value, and when the first difference is within a preset difference range, it is determined that the verification result meets the standard, and the position and angle of each antenna module are recorded;

[0043] Alternatively, verification is performed based on a second difference between the average transmission power test values ​​of the multiple preset products and the average laboratory test values. When the second difference is within a preset difference range, the verification result is determined to be up to standard, and the position and angle values ​​of each antenna module are recorded.

[0044] The present invention also provides a multi-antenna test system, the multi-antenna test system comprising:

[0045] Test fixtures;

[0046] Comprehensive tester;

[0047] Multiple antenna modules, the relative positions of the multiple antenna modules and the test fixture are different, and multiple transmission channels are formed between each product to be tested placed in the test fixture and the multiple antenna modules and the comprehensive tester; and,

[0048] The host computer comprises: a memory and a processor. The memory stores a calibration program for a multi-antenna test system. When the calibration program for a multi-antenna test system is executed by the processor, the steps of the calibration method for a multi-antenna test system as described above are implemented.

[0049] Optionally, the multi-antenna testing system further includes:

[0050] A shielding box, in which the test fixture is fixed;

[0051] The plurality of antenna modules are arranged on the side wall and the upper wall of the shielding box.

[0052] Optionally, the multi-antenna testing system further includes:

[0053] A radio frequency switch, wherein the multiple first ends of the radio frequency switch are connected to the multiple antenna modules in a one-to-one correspondence; and the second end of the radio frequency switch is connected to the comprehensive tester.

[0054] Optionally, the plurality of antenna modules are orthogonal antenna modules, each of the orthogonal antenna modules is positionally adjustable in a preset direction, and each of the orthogonal antenna modules is capable of rotating 180 degrees along a preset direction.

[0055] The present invention proposes a multi-antenna test system calibration method, which uses the correlation between the laboratory TRP test (Total Radiated Power) and the power (Power) test of the uplink channel (Tx or Uplink channel) of the test system, and uses the least squares linear regression analysis method to model, which can quickly find the position and angle value of each antenna module, which can be a frequency band corresponding to the product to be tested, so as to select the antenna module with better matching with the product to be tested, and realize the calibration of the corresponding antenna test channel, and pass the laboratory standard to the production line test system, that is, to achieve a plurality of different antenna modules respectively with different functional antennas of the product, or to find a plurality of antenna modules and a certain function of the product respectively good coupling, or to find a plurality of different antenna modules and a plurality of antennas of a certain function of the product respectively good coupling, to meet the multi-antenna OTA test requirements. Compared with the current blind experimental verification of each antenna, when it is found that the instability or poor consistency is found during use, it can only be replaced with other antenna modules to continue to try to verify, the cycle is long, and the final result is uncertain. Now the complex matching antenna selection and calibration process is streamlined, which greatly reduces the complexity and workload. The calibrated test system can be used to test the polarized antenna of the entire product under test, which is beneficial to improving the work efficiency of antenna testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0056] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0057] Figure 1 A schematic diagram of a flow chart of an embodiment of a multi-antenna test system calibration method of the present invention;

[0058] Figure 2 A schematic diagram of a flow chart of another embodiment of a multi-antenna test system calibration method of the present invention;

[0059] Figure 3 middle Figure 2 A detailed flow chart of step S700 in an embodiment;

[0060] Figure 4 It is a structural schematic diagram of an embodiment of a multi-antenna test system of the present invention;

[0061] Figure 5 for Figure 4 A schematic structural diagram of an embodiment of an antenna module;

[0062] Figure 6 for Figure 4 A top view of an embodiment of an antenna module;

[0063] Figure 7 It is a structural diagram of an embodiment of the hardware architecture of a multi-antenna test system of the present invention.

[0064] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0065] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0066] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0067] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0068] The term "and / or" in this article is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0069] The present invention proposes a calibration method for a multi-antenna test system. The multi-antenna test system has a test fixture, a comprehensive tester and multiple antenna modules. The multiple antenna modules have different relative positions and angles to the test fixture. Multiple transmission channels are formed between each product to be tested placed on the test fixture and the multiple antenna modules and the comprehensive tester.

[0070] With the rapid development and popularization of voice recognition, smart home, AR / VR and wearable products, more and more products integrate multiple wireless technology functions such as Bluetooth, Zigbee and WiFi, and even a single product integrates multiple WiFi or UWB antennas; in order to meet the performance index requirements of the whole product design, all products produced need to be calibrated or tested to intercept defective products. It is easy to find matching antennas for different products when they are calibrated or tested separately. However, smart products nowadays are often system-level, and the startup time is relatively long. Separate testing wastes time and a lot of manpower, material and financial resources. Therefore, it is the best choice to put the antennas of whole products with different functions in the same test system for serial testing. At present, it is difficult to find an antenna module with a single position or angle that can be compatible with all antennas of the matching product to achieve stable testing at the same time, and it is difficult to ensure good correlation between laboratory test data and production line test systems; usually, multiple antenna modules in different positions or directions can be found to match antennas with different functions of the product or to couple and match with different antennas of a certain function of the product or different frequency bands (Bluetooth 2G and 5G, WiFi2.4G and 5G) separately. How to quickly determine the position and direction of the matching antenna module, realize the line loss calibration of the matching antenna module channel, align the production line test system with the laboratory test, ensure the stability and consistency of the test system test, complete the fast and accurate OTA (over the air) test of multiple antennas of the whole product, and ensure product quality is a topic worthy of research.

[0071] For this purpose, refer to Figure 1 In one embodiment of the present invention, the calibration method of the multi-antenna test system includes:

[0072] Step S100, sequentially testing the transmission power of multiple first products to be tested placed in the test fixture in each frequency band on different transmission channels, and obtaining corresponding transmission power data;

[0073] In this embodiment, a certain number of products are taken from the products to be tested as temporary standard samples, and the test system is used to test the transmission power (Tx Power) of the products in each frequency band under different antennas. When the transmission power test is performed on multiple first products to be tested, one product to be tested is placed in the test fixture each time, and the products to be tested are controlled to transmit excitation signals of different frequencies, and then the transmission power data sent by the products to be tested is received through each test channel, that is, the signal T i(Post-TxPower), so as to obtain the transmission power of each product under test in each channel and each frequency band.

[0074] In this embodiment, the number of antenna modules is multiple, specifically 8, and the 8 antenna modules are arranged and arranged on the left, right, back and top inner sides of the shielding box. The position and rotation angle between each antenna can be set to be different. The 8 antenna modules are orthogonal antenna modules. The top is the 1# antenna module, which can realize the position movement adjustment in the four directions of left, right, front and back and 180-degree rotation in the horizontal direction (and the stepping Step can be set to 30 degrees or 45 degrees); the right side is the antenna 2~4# module and the left side is the antenna 6~8# module, which can realize the position adjustment in the front and back and up and down directions, and a single antenna module can realize the vertical direction 180-degree rotation (Step: 30 degrees or 45 degrees); the back side is the antenna 5# module, which can realize the position adjustment in the left, right, up and down directions, and a single antenna module can realize the vertical direction 180-degree rotation (Step: 30 degrees or 45 degrees). All angles of the upper hemisphere of the product can be covered as much as possible to find the coupling position and angle that can best match the product antenna. The eight antenna modules can form eight test channels with the integrated tester. When calibrating the antenna, the antenna module required for the test can be selected from the eight antenna modules according to the type of antenna integrated in the product, the number of antennas, etc., and the radiation frequency band of the antenna. The number of selected test channels will also vary with the different tested products. And during calibration, the corresponding test channel can be turned on in a preset order, so that the excitation signals of different frequencies emitted by the antenna of the product to be tested can be received through the antenna module. That is, when a test channel is turned on, the product to be tested can be controlled to radiate outward in turn, and the antenna inside the product can radiate each frequency band, so that each antenna module in the selected antenna module can receive a set of excitation signals sent by the product to be tested, that is, the transmission power of each antenna frequency band of the product to be tested. In this way, each test channel is turned on in turn according to the preset order, and when the channel is turned on, the transmission power of each antenna frequency band of the product to be tested can be received.

[0075] Step S200: performing a Total Radiated Power (TRP) test on a plurality of first products to be tested in sequence, and obtaining corresponding Total Radiated Power data;

[0076] In this embodiment, the omnidirectional radiated power test can be obtained by laboratory testing. Specifically, the first product to be tested is subjected to a laboratory TRP test in the laboratory and the test values ​​corresponding to different frequency bands are recorded, which are recorded as TRP(i, f), i=1~10, f=2402MHz, 2441MHz, 2480MHz, wherein i is the i-th product to be tested; f is the frequency band during the test. In this embodiment, the product to be tested that can transmit excitation signals in three frequency bands of f=2402MHz, 2441MHz, and 2480MHz is tested and calibrated.

[0077] Step S300: performing a linear regression model analysis based on the least squares method on the acquired transmission power data and omnidirectional radiation power data;

[0078] In this embodiment, the acquired transmission power data and omnidirectional radiation power data are processed: TRP data and T xPower The data were analyzed by linear regression modeling based on the least squares method.

[0079] Let xi = TRP(f, i), yi = T 0(Post-TxPower) (f, i, p, V, H), f represents different frequency bands, i represents the product number, P represents the position of the antenna, V represents the rotation angle of the antenna in the vertical plane; H represents the rotation angle of the antenna in the horizontal plane.

[0080] Establish a univariate linear regression model, specifically:

[0081] Y i =αX i +β+ε i , (i=1, 2, ..., n);

[0082] In the formula, αX i +β is a linear function, ε i are random errors and are independent of each other.

[0083] The linear coefficient α and its estimated value in the univariate linear regression model are obtained from the transmission power data, isotropic radiated power data and their observed values The intercept β and its estimated value and the residual square σ 2 and its estimated value Get the estimated formula of the empirical equation:

[0084]

[0085] Construct the Q(xi,yi) function:

[0086]

[0087] That is to find Make Q minimum. Where, is the observed value of the sample. The selected regression model is based on the least squares method to minimize the residual sum of squares of all observed values. The problem is converted into the problem of finding the extreme value of Q function.

[0088] Find the partial derivative of Q with respect to a and b;

[0089]

[0090] We get the system of equations:

[0091]

[0092] The solution is:

[0093]

[0094] Calculate the correlation coefficient R:

[0095]

[0096] in,

[0097] After calculating the correlation coefficient R, you can get the square of the correlation coefficient R 2 , R 2 It is an indicator for evaluating the quality of the regression model. Numerically speaking, R 2 Between 0 and 1, the closer it is to 1, the better the regression fitting effect.

[0098] Step S400: After adjusting the position and / or angle of the antenna module on each transmission channel, return to execute step S100 until an antenna module that best matches the product to be tested among the multiple antenna modules is obtained;

[0099] In this embodiment, according to the selection principle of the best matching antenna:

[0100] In y=ax+b, x refers to the TRP test value; y refers to the T xPower Test value; slope a is positive, indicating that the laboratory TRP and test system T xPower Positive correlation, the value is generally [0.5, 1), the larger the a, the better. 2 Between 0 and 1, the closer to 1, the better the regression fitting effect. Switch different positions or angles of the antenna to adjust the position and / or angle of the antenna module on each transmission channel, and repeat the above test of steps S100-S300 until the linear coefficient a and the correlation coefficient R are obtained. 2 To determine the best matching antenna.

[0101] Step S500: Select a first preset number of calibration products and sequentially place them into a test fixture to calibrate the line loss of each transmission channel of the test system;

[0102] In this embodiment, multiple standard products are selected for use. This embodiment uses three products as an example for description. Specifically, laboratory tests can be performed to select products with OK and relatively stable standard performance and laboratory test values ​​as standard products. Pathloss calibration is performed on the corresponding channel. For details, please refer to step 700; three standard products are used to obtain the calibration data of their Tx channels respectively, and the three offset values ​​are averaged and automatically updated to the offset of the corresponding channel of the host computer. At the same time, the Pathloss Offset value of the Rx channel of the corresponding antenna is set to be the same as the corresponding Tx channel.

[0103] Step S600: Select a preset number of standard sample products to verify the calibration of the test system, and when the verification result meets the standard, record the position and angle of each antenna module to find the coupling position and angle that can best match the product antenna.

[0104] Specifically, a transmission power test is performed on a preset number of standard sample products, and an average transmission power test value of multiple preset products is obtained;

[0105] Verification is performed based on a first difference between the test average value and the target value, and when the first difference is within a preset difference range, it is determined that the verification result meets the standard, and the position and angle of each antenna module are recorded;

[0106] Alternatively, verification is performed based on a second difference between the average transmission power test values ​​of the multiple preset products and the average laboratory test values. When the second difference is within a preset difference range, the verification result is determined to be up to standard, and the position and angle values ​​of each antenna module are recorded.

[0107] In this embodiment, several common products are used to test the test system, and then the laboratory test is carried out. If the difference is within 0.5dB, the calibration is considered OK, that is, the verification result is determined to meet the standard, otherwise it is necessary to adapt and recalibrate. When calibrating to the Target value, the three standard products T xPower The average value of the test is compared with the target value. If the difference is within the range of 0.5-1dB, the calibration is considered OK. Otherwise, recalibration is required. When using the calibration to the standard laboratory test value, the test system T of these three products needs to be xPower The test average value is compared with the laboratory average test value of 3 standard products. If the difference is within the range of 0.5-1dB, the calibration is considered OK, otherwise recalibration is required.

[0108] The present invention proposes a multi-antenna test system calibration method, which uses the correlation between the laboratory TRP test (Total Radiated Power) and the power (Power) test of the uplink channel (Tx or Uplink channel) of the test system, and uses the least squares linear regression analysis method to model, which can quickly find the position and angle value of each antenna module, which can be a frequency band corresponding to the product to be tested, so as to select the antenna module with better matching with the product to be tested, and realize the calibration of the corresponding antenna test channel, and pass the laboratory standard to the production line test system, that is, to achieve a plurality of different antenna modules respectively with different functional antennas of the product, or to find a plurality of antenna modules and a certain function of the product respectively good coupling, or to find a plurality of different antenna modules and a plurality of antennas of a certain function of the product respectively good coupling, to meet the multi-antenna OTA test requirements. Compared with the current blind experimental verification of each antenna, when it is found that the instability or poor consistency is found during use, it can only be replaced with other antenna modules to continue to try to verify, the cycle is long, and the final result is uncertain. Now the complex matching antenna selection and calibration process is streamlined, which greatly reduces the complexity and workload. The calibrated test system can be used to test the polarized antenna of the entire product under test, which is beneficial to improving the work efficiency of antenna testing.

[0109] Reference Figure 2 and Figure 3 In one embodiment, before step S100, the calibration method of the multi-antenna test system further includes:

[0110] Step S700: pre-calibrate the line loss of each transmission channel of the test system.

[0111] In this embodiment, each transmission channel (Tx) of the test system is pre-calibrated. Step S700 specifically includes:

[0112] Step S710, randomly selecting one of the multiple products to be tested as a temporary standard sample, and placing it in the test fixture, switching the selected multiple transmission channels in turn according to a preset order, and when each transmission channel is turned on, controlling the temporary standard sample to sequentially send excitation signals of multiple preset frequency bands to obtain the radio frequency signal received by the antenna module in the transmission channel;

[0113] Step S720: performing line loss analysis on the acquired radio frequency signals of the multiple channels to obtain compensated line loss data of each transmission channel;

[0114] Step S730: Compensate the compensated line loss data into the test system.

[0115] Randomly select a product from the same batch of products as a temporary standard sample, and perform path loss calibration on multiple antennas (four for example) of the test system at the default position and default angle. Or directly use a temporary standard sample selected by the laboratory to pre-calibrate the path loss. The specific calibration steps are as follows:

[0116] The following is an example of the low (2402MHz), medium (2441MHz), and high (2480MHz) frequency bands of the Bluetooth antenna BT.

[0117] Step 1: In actual application, the preset Path loss value of each channel can be set on the host computer configuration interface (for example, Pre-Set: 30dB, other values ​​can be selected based on experience), the host computer controls the RF Switch Box to switch to one of the selected channels, such as channel 0, the host computer controls the DUT to send an excitation signal S(f), for example, f = 2402MHz, BW = 1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module. 0 (f)|f=2402MHz and transmit it back to the host computer; then the host computer controls the DUT to send the excitation signal S(f), for example, f=2441MHz, BW=1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module 0 (f)|f=2441MHz and transmit it back to the host computer; the host computer controls the DUT to send the excitation signal S(f), for example, f=2480MHz, BW=1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module 0 (f)|f=2480MHz and sent back to the host computer.

[0118] The host computer controls the RF Switch Box to switch to channel 1. The host computer controls the DUT to send stimulus signals S(f), f=2402MHz, f=2441MHz, f=2480MHz BW=1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module. 1 (f), f = 2402MHz, f = 2441MHz, f = 2480MHz and are transmitted back to the host computer respectively;

[0119] The host computer controls the RF Switch Box to switch to channel 2. The host computer controls the DUT to send stimulus signals S(f), f=2402MHz, f=2441MHz, f=2480MHz BW=1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module. 2(f), f = 2402MHz, f = 2441MHz, f = 2480MHz and are transmitted back to the host computer respectively;

[0120] The host computer controls the RF Switch Box to switch to channel 3. The host computer controls the DUT to send stimulus signals S(f), f=2402MHz, f=2441MHz, f=2480MHz BW=1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module. 3 (f), f = 2402MHz, f = 2441MHz, f = 2480MHz and are transmitted back to the host computer respectively;

[0121] Step 2: The host computer analyzes the data of each channel T 0 (f), T 1 (f), T 2 (f), T 3 (f), f=2402MHz, 2441MHz, 2480MHz;

[0122] The line loss data is calculated using the following formula:

[0123] Pathloss(f)(Chn)=Pre-Set(30dB)+(Target(dB)-(Tn(f))); f=2402MHz, 2441MHz, 2480MHz;

[0124] Or, Pathloss(f)(Chn)=Pre-Set(30dB)+(laboratory test value-(Tn(f)); f=2402MHz, 2441MHz, 2480MHz; where,

[0125] Pathloss(f)(Chn) is the line loss value when the nth transmission channel among the selected multiple transmission channels is turned on, Pre-Set(30dB) is the preset line loss value, Target(dB) is the target line loss value, (Tn(f) is the actual line loss value when the nth transmission channel is turned on, and Chn is the channel number.

[0126] This embodiment takes 4 channels as an example for explanation, and the line loss data of each channel can be obtained by using the following formula:

[0127] Pathloss(f)(Ch0)=Pre-Set(30dB)+(Target(dB)-T 0 (f)); f = 2402MHz, 2441M

[0128] Hz, 2480MHz.

[0129] Pathloss(f)(Ch1)=Pre-Set(30dB)+(Target(dB)-T 1 (f)); f = 2402MHz, 2441M

[0130] Hz, 2480MHz.

[0131] Pathloss(f)(Ch2)=Pre-Set(30dB)+(Target(dB)-T 2 (f)); f = 2402MHz, 2441M

[0132] Hz, 2480MHz.

[0133] Pathloss(f)(Ch3)=Pre-Set(30dB)+(Target(dB)-T 3 (f)); f = 2402MHz, 2441M

[0134] Hz, 2480MHz.

[0135] Or if laboratory standards are used, the compensation data for each channel is:

[0136] Pathloss(f)(Ch0)=Pre-Set(30dB)+(Laboratory Test Value-T 0 (f)); f=2402MHz, 2441MHz, 2480MHz.

[0137] Pathloss(f)(Ch1)=Pre-Set(30dB)+(Laboratory Test Value-T 1 (f)); f=2402MHz, 2441MHz, 2480MHz.

[0138] Pathloss(f)(Ch2)=Pre-Set(30dB)+(Laboratory Test Value-T 2 (f)); f=2402MHz, 2441MHz, 2480MHz.

[0139] Pathloss(f)(Ch3)=Pre-Set(30dB)+(Laboratory Test Value-T 3 (f)); f=2402MHz, 2441MHz, 2480MHz.

[0140] Step 4: Update the actual Pathloss (f) (Ch0, Ch1, Ch2, Ch3), f = 2402MHz, 2441MHz, 2480MHz to the offset table of each channel frequency band of the host computer for use in actual testing. In some embodiments, the received power of the antenna can also be tested, which can be achieved through the Rx channel of the antenna. The Pathloss Offset value of the Rx channel of the corresponding antenna is set to the same as the corresponding Tx channel. (The Rx channel is the receiving channel, also known as the downlink channel).

[0141] Reference Figures 1 to 3 In one embodiment, the step S100 specifically includes:

[0142] Multiple products to be tested are placed in the test fixture in sequence, and the selected multiple transmission channels are switched on in turn according to the preset order. When each transmission channel is turned on, the products to be tested are controlled to send excitation signals of preset frequency bands in sequence according to the preset order to obtain the transmission power of the products to be tested in each frequency band on different channels.

[0143] In this embodiment, the number of products to be tested can be 10. Take 10 products to be tested as temporary standards, mark the 10 temporary standards as DUT1-DUT10 respectively, and test the transmission power (Tx Power) of the product in each frequency band under different antennas of the test system.

[0144] Specifically, Step 1: Take the DUT 1 (temporary standard sample) is placed in the test fixture, and the host computer is started to start the test. The host computer controls the test channel to switch to channel 0. The host computer controls the DUT to send the excitation signal S1(f), f = 2402MHz, 2441MHz, 2480MHz, BW = 1MHz, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module. 0(TxPower) (f, i), f = 2402MHz, 2441MHz, 2480MHz, i = 1 and sent back to the host computer; the host computer controls the test channel to switch to channel 1, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module 1(TxPower) (f, i), f = 2402MHz, 2441MHz, 2480MHz, i = 1 and sent back to the host computer; the host computer controls the test channel to switch to channel 2, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module 2(TxPower) (f, i)f=2402MHz, 2441MHz, 2480MHz, i=1 and sent back to the host computer; the host computer controls the test channel to switch to channel 3, and controls the wireless comprehensive tester to receive the signal T sent by the DUT through the antenna module3(TxPower) (f, i)f=2402MHz, 2441MHz, 2480MHz, i=1 and transmitted back to the host computer.

[0145] Step 2: The host computer analyzes the data of each channel T 0(TxPower) (f,i),T 1(TxPower) (f,i),T 2(TxPowe r) (f,i),T 3(TxPower) (f, i); f=2402MHz, 2441MHz, 2480MHz, BW=1MHz.

[0146] Step 3: Data post-processing, the host computer analyzes the data of each channel 0(Post-TxPower) (f,i),T 1(Post-Tx Power) (f,i),T 2(Post-TxPower) (f,i),T 3(Post-TxPower) (f, i); f=2402MHz, 2441MHz, 2480MHz, BW=1MHz; i=1

[0147] T 0(Post-TxPower) (f, i) = T 0(TxPower) (f, i) + Pathloss (f) (Ch0); f = 2402MHz, 2441

[0148] MHz, 2480MHz, BW=1MHz; i=1

[0149] T 1(Post-TxPower) (f, i) = T 1(TxPower) (f, i) + Pathloss (f) (Ch1); f = 2402MHz, 2441M

[0150] Hz, 2480MHz, BW=1MHz; i=1

[0151] T 2(Post-TxPower) (f, i) = T 2(TxPower) (f, i) + Pathloss (f) (Ch2); f = 2402MHz, 2441M

[0152] Hz, 2480MHz, BW=1MHz; i=1

[0153] T 3(Post-TxPower) (f, i) = T 3(TxPower) (f, i) + Pathloss (f) (Ch3); f = 2402MHz, 2441M

[0154] Hz, 2480MHz, BW=1MHz; i=1

[0155] Similarly, the same test is performed on DUT2 to DUT10 to obtain data of 10 products under different test system configurations, and the omnidirectional radiated power data obtained by the laboratory and the transmission power data obtained by the system test are listed. The TRP test values ​​of all tested products and the OTA TxPower test values ​​of different antennas at certain positions and rotation angles are summarized. See Table 1 for details. Table 1 shows the omnidirectional radiated power data obtained in the laboratory and the transmission power data obtained by the system test (TRP Vs OT A TxPower test value).

[0156] T 0(Post-TxPower) (f, i) = T 0(TxPower) (f, i) + Pathloss (f) (Ch0); f = 2402MHz, 2441

[0157] MHz, 2480MHz, BW=1MHz; i=2~10.

[0158] T 1(Post-TxPower) (f, i) = T 1(TxPower) (f, i) + Pathloss (f) (Ch1); f = 2402MHz, 2441

[0159] MHz, 2480MHz, BW=1MHz; i=2~10.

[0160] T 2(Post-TxPower) (f, i) = T 2(TxPower) (f, i) + Pathloss (f) (Ch2); f = 2402MHz, 2441

[0161] MHz, 2480MHz, BW=1MHz; i=2~10.

[0162] T 3(Post-TxPower) (f, i) = T 3(TxPower) (f, i) + Pathloss (f) (Ch3); f = 2402MHz, 2441

[0163] MHz, 2480MHz, BW=1MHz; i=2~10.

[0164] Table 1

[0165]

[0166]

[0167] The present invention also provides a multi-antenna testing system.

[0168] Reference Figures 4 to 6, the multi-antenna test system includes:

[0169] Test fixture 10;

[0170] Comprehensive tester 20;

[0171] A plurality of antenna modules 30, wherein the relative positions of the plurality of antenna modules 30 and the test fixture 10 are different, and a plurality of transmission channels are formed between each product to be tested placed in the test fixture 10 and the plurality of antenna modules 30 and the comprehensive tester 20; and,

[0172] The host computer 40 includes: a memory and a processor. The memory stores a calibration program for a multi-antenna test system. When the calibration program for a multi-antenna test system is executed by the processor, the steps of the calibration method for a multi-antenna test system as described above are implemented.

[0173] A shielding box 50, in which the test fixture 10 is fixed;

[0174] The plurality of antenna modules 30 are disposed on the side walls and the upper wall of the shielding box 50 .

[0175] In this embodiment, the test fixture 10 can be provided with a carrier for placing the product to be tested and a circuit function module for communicating with the host computer 40, so that the control instructions sent by the host computer 40 to the product to be tested can be received by the test fixture 10 and output to the product to be tested, and the product to be tested can also feedback the information, data parameters, etc. during the test to the host computer 40 through the test fixture 10. The comprehensive tester 20 is provided with an excitation signal generation and signal analysis module, etc. When testing the antenna, a receiving channel, i.e., an Rx channel, also called a downlink channel, can be formed with the antenna module 30 through the RF switch 60, and a radiation signal can be emitted to the antenna module 30 to achieve the test of the antenna receiving power, etc. The comprehensive tester 20 can calculate the transmission power of the product to be tested according to the RF signal generated by the excitation of the product to be tested received by the antenna module 30, and output it to the host computer 40 to complete the transmission power test of the product to be tested. The plurality of antenna modules 30 are orthogonal antenna modules 30, each of which is adjustable in a preset direction, and each of which can rotate 180 degrees along a preset direction. The host computer 40 can be implemented by a computer, which is loaded with software capable of completing the test and has built an operating environment required to complete the test. The shielding box 50 is provided with an antenna access interface for connecting the antenna module 30 to the comprehensive tester 20, and a communication interface, such as a USB interface, for the test fixture 10 to communicate with the host computer 40. With the help of the customized shielding box 50 and its internal modular 8 antenna modules 30, the 8 antenna modules 30 are arranged and divided on the left, right, back and top inner sides of the shielding box 50. The 8 antenna modules 30 are orthogonal antenna modules 30. The top is 1# antenna module 30, which can realize the position adjustment in the four directions of left, right, front and back and 180-degree rotation in the horizontal direction (Step: 30 degrees or 45 degrees); the right side is antenna 2~4# modules and the left side is antenna 6~8# modules, which can realize the position adjustment in the front and back and up and down directions, and a single antenna module 30 can realize 180-degree rotation in the vertical direction (Step: 30 degrees or 45 degrees); the back side is antenna 5# module, which can realize the position adjustment in the left, right, up and down directions, and a single antenna module 30 can realize 180-degree rotation in the vertical direction (Step: 30 degrees or 45 degrees). All angles of the upper hemisphere of the product can be covered as much as possible to find the coupling position and angle that can best match the product antenna. The eight antenna modules 30 can form eight test channels with the integrated tester 20. When calibrating the antenna, the antenna module 30 required for the test can be selected from the eight antenna modules 30 according to the type of antennas integrated in the product, the number of antennas, etc., and the radiation frequency band of the antenna. During calibration, the corresponding test channel can be turned on so that the antenna module 30 receives excitation signals of different frequencies emitted by the antenna of the product to be tested.That is, when a test channel is turned on, the product to be tested can be controlled to radiate outward in turn, and the antenna inside the product can radiate each frequency band, so that each antenna module 30 in the selected antenna module 30 can receive a set of excitation signals sent by the product to be tested, that is, the transmission power of each frequency band of the product to be tested. By using the correlation between the laboratory TRP test (Total Radiated Power) and the power (Power) test of the uplink channel (Tx or Uplink channel) of the test system, and modeling with the help of the linear regression analysis method based on the least squares method, the best matching antenna module 30 can be quickly selected and the corresponding antenna test channel can be calibrated, and the laboratory standard can be passed to the production line test system, that is, multiple different antenna modules 30 can be well coupled with antennas of different functions of the product, or multiple antenna modules 30 can be well coupled with different frequency bands of a certain function of the product, or multiple different antenna modules 30 can be well coupled with multiple antennas of a certain function of the product, to meet the multi-antenna OTA test requirements. Compared with the current test system, which performs experimental verification on each antenna without purpose, and can only replace other antenna modules 30 for further verification when instability or poor consistency is found during use, the cycle is long and the final result is uncertain, the complex matching antenna selection and calibration process is now streamlined, greatly reducing the complexity and workload. It can be extended to home, hearable and wearable products.

[0176] Reference Figures 4 to 6 In one embodiment, the multi-antenna test system further includes:

[0177] A radio frequency switch (RF Switch Box) 60 , wherein a plurality of first ends of the radio frequency switch 60 are connected to a plurality of the antenna modules 30 in a one-to-one correspondence; and a second end of the radio frequency switch 60 is connected to the comprehensive tester 20 .

[0178] In this embodiment, the number of RF switches 60 can be multiple, and they are set according to the number of corresponding antenna modules 30. The RF switches 60 are controlled by the host computer 40. Each RF switch 60 can control whether the antenna module 30 is electrically connected to the comprehensive tester 20, thereby controlling the on / off of a test channel. Alternatively, the RF switch 60 can also be implemented by a single-pole multi-throw switch. When the single-pole multi-throw switch is switched to an antenna module 30, an antenna module 30 can be electrically connected to the comprehensive tester 20, thereby controlling the on / off of a test channel. When the test channel is turned on, the corresponding antenna module 30 can receive the excitation signal sent by the product to be tested, that is, the transmission power of each frequency band of the product to be tested.

[0179] The present invention also provides a readable storage medium, on which a computer program is stored, and when the computer program is executed by the processor 101, the steps of the audio processing method of the multi-antenna test system described above are implemented. In the embodiments of the multi-antenna test system and the computer-readable storage medium provided by the present invention, all technical features of the various embodiments of the audio processing method of the multi-antenna test system described above are included, and the expansion and explanation content of the specification are basically the same as those of the various embodiments of the method described above, and will not be repeated here.

[0180] Reference Figure 7 The terminal of the embodiment of the present invention may be a PC, or a smart phone, a tablet computer, an e-book reader, an MP4 (Moving Picture Experts Group Audio Layer IV) player, a portable computer, or other mobile terminal devices with display functions. Figure 1 The terminal may include a processor 101 (such as a CPU), a communication bus 102, a user interface 103, a network interface 104, and a memory 105. The communication bus 102 is used to realize the connection and communication between these components; the user interface 103 may include a display screen (Display), an input unit such as a keyboard (Keyboard); the network interface 104 may optionally include a standard wired interface, etc.; the memory 105 may be a high-speed RAM memory 105, or a stable memory 105 (non-volatile memory), such as a disk memory 105, and the memory 105 may also be a storage device independent of the aforementioned processor 101.

[0181] Those skilled in the art will understand that Figure 7 The terminal structure of the multi-antenna test system hardware operating environment shown in the figure does not constitute a limitation on the multi-antenna test system of the present invention, and may include more or less components than shown in the figure, or a combination of certain components, or a different arrangement of components.

[0182] The above descriptions are only optional embodiments of the present invention, and are not intended to limit the patent scope of the present invention. All equivalent structural changes made using the contents of the present invention's specification and drawings, or directly / indirectly applied in other related technical fields, are included in the patent protection scope of the present invention.

Claims

1. A calibration method for a multi-antenna test system, characterized in that: The multi-antenna test system comprises a test fixture, a comprehensive tester and a plurality of antenna modules. The relative positions and angles between the plurality of antenna modules and the test fixture are different. A plurality of transmission channels are formed between each product to be tested placed in the test fixture and the plurality of antenna modules and the comprehensive tester. The calibration method of the multi-antenna test system comprises: Step S100, sequentially testing the transmission power of multiple first products to be tested placed in the test fixture in each frequency band on different transmission channels, and obtaining corresponding transmission power data; Step S200, performing omnidirectional radiation power tests on a plurality of first products to be tested in sequence, and obtaining corresponding omnidirectional radiation power data; Step S300: performing a linear regression model analysis based on the least squares method on the acquired transmission power data and omnidirectional radiation power data; Step S400: After adjusting the position and / or angle of the antenna module on each transmission channel, return to execute step S100 until an antenna module that best matches the product to be tested among the multiple antenna modules is obtained; Step S500: Select a first preset number of calibration products and sequentially place them into a test fixture to calibrate the line loss of each transmission channel of the test system; Step S600: Select a preset number of standard sample products to verify the calibration of the test system, and when the verification result meets the standard, record the position and angle of each antenna module.

2. The calibration method of a multi-antenna test system according to claim 1, characterized in that: Before step S100, the calibration method of the multi-antenna test system further includes: Step S700: pre-calibrate the line loss of each transmission channel of the test system.

3. The calibration method of a multi-antenna test system according to claim 2, characterized in that: The step S700 specifically includes: Step S710, randomly selecting one of the multiple products to be tested as a temporary standard sample, and placing it in the test fixture, switching the selected multiple transmission channels in turn according to a preset order, and when each transmission channel is turned on, controlling the temporary standard sample to sequentially send excitation signals of multiple preset frequency bands to obtain the radio frequency signal received by the antenna module in the transmission channel; Step S720: performing line loss analysis on the acquired radio frequency signals of the multiple channels to obtain compensated line loss data of each transmission channel; Step S730: Compensate the compensated line loss data into the test system.

4. The calibration method of a multi-antenna test system according to claim 3, characterized in that: The line loss data is calculated using the following formula: Pathloss(f)(Chn)=Pre-Set(30dB)+(Target(dB)-(Tn(f))); f=2402MHz, 2441MHz, 2480MHz; Or, Pathloss(f)(Chn)=Pre-Set(30dB)+(laboratory test value-(Tn(f)); f=2402MHz, 2441MHz, 2480MHz; where, Pathloss(f)(Chn) is the line loss value when the nth transmission channel among the selected multiple transmission channels is turned on, Chn is the channel number, Pre-Set(30dB) is the preset line loss value, Target(dB) is the target line loss value, (Tn(f) is the actual line loss value when the nth transmission channel is turned on.

5. The calibration method of a multi-antenna test system according to claim 1, characterized in that: The step S100 specifically includes: Multiple products to be tested are placed in the test fixture in sequence, and the selected multiple transmission channels are switched on in turn according to the preset order. When each transmission channel is turned on, the products to be tested are controlled to send excitation signals of preset frequency bands in sequence according to the preset order to obtain the transmission power of the products to be tested in each frequency band on different channels.

6. The calibration method of a multi-antenna test system according to claim 1, characterized in that: The step S300 specifically includes: Establish a univariate linear regression model, specifically: Y i =αX i +β+ε i ,(i=1,2,…,n); In the formula, αX i +β is a linear function, X i is the TRP test value; Y i For OTA test station T xPower Test value, ε i are random errors, independent of each other; The linear coefficient α and its estimated value in the univariate linear regression model are obtained from the transmission power data, isotropic radiated power data and their observed values The intercept β and its estimated value and the residual square σ 2 and its estimated value Get the estimated formula of the empirical equation: Construct the Q(xi,yi) function: Find the partial derivative of Q with respect to a and b; We get the system of equations: The solution is: Calculate the correlation coefficient R: in, 7. The calibration method of a multi-antenna test system according to any one of claims 1 to 6, characterized in that: The step S600 specifically includes: Perform transmission power tests on a preset number of standard sample products, and obtain the transmission power test average value of multiple preset products; Verification is performed based on a first difference between the test average value and the target value, and when the first difference is within a preset difference range, it is determined that the verification result meets the standard, and the position and angle of each antenna module are recorded; Alternatively, verification is performed based on a second difference between the average transmission power test values ​​of the multiple preset products and the average laboratory test values. When the second difference is within a preset difference range, the verification result is determined to be up to standard, and the position and angle values ​​of each antenna module are recorded.

8. A multi-antenna test system, characterized in that: The multi-antenna test system includes: Test fixtures; Comprehensive tester; Multiple antenna modules, the relative positions of the multiple antenna modules and the test fixture are different, and multiple transmission channels are formed between each product to be tested placed in the test fixture and the multiple antenna modules and the comprehensive tester; and, A host computer, the host computer comprising: a memory and a processor, wherein the memory stores a calibration program for a multi-antenna test system, and when the calibration program for the multi-antenna test system is executed by the processor, the steps of the calibration method for the multi-antenna test system as described in any one of claims 1 to 7 are implemented.

9. The multi-antenna test system according to claim 8, characterized in that: The multi-antenna test system further comprises: A shielding box, in which the test fixture is fixed; The plurality of antenna modules are arranged on the side wall and the upper wall of the shielding box.

10. The multi-antenna testing system according to claim 8, characterized in that: The multi-antenna test system further comprises: A radio frequency switch, wherein the multiple first ends of the radio frequency switch are connected to the multiple antenna modules in a one-to-one correspondence; and the second end of the radio frequency switch is connected to the comprehensive tester.

11. The multi-antenna test system according to claim 8, characterized in that: The plurality of antenna modules are orthogonal antenna modules, each of which is adjustable in a preset direction, and each of which is capable of rotating 180 degrees along a preset direction.

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