Method for testing absolute radiated power of end product based on source stirred reverberation chamber

Abstract

The application discloses a terminal product absolute radiation power test method based on a source stirring reverberation test box, which comprises a source stirring reverberation test box, a signal generator, a signal receiving circuit and a spectrum analyzer; a withdrawable tray is arranged in a shielding cavity of the test box, and a plurality of signal receiving antennas are arranged around the tray in the shielding cavity; and the test steps comprise: sequentially placing and measuring the emission signals of a reference antenna, a virtual reference antenna, a measured terminal product and a virtual terminal product antenna in the shielding cavity, and finally obtaining the absolute TRP value of the measured terminal product through calculation and processing. The application can directly test the TRP in the production line by using the source stirring reverberation chamber, without the need of placing the product into a standard darkroom for calibration test, and is beneficial to the rapid iteration of the product.

Description

Technical Field

[0001] This invention relates to the field of microwave communication technology, and in particular to a method for testing the absolute radiated power of terminal products based on a source stirring reverberation test chamber. It is applicable to production line testing of terminal products and is used for testing the total radiated power (TRP) of the main frequency of terminal products. Background Technology

[0002] Currently, with the arrival of the 5G era, terminal products are gradually expanding from low-frequency narrowband coverage to high-frequency broadband coverage. System integration and complexity are also increasing exponentially, requiring multi-band, multi-antenna TRP (Total Recovery Point) testing. Typically, testing the TRP of terminal products requires a spherical multi-probe anechoic chamber, using an algorithm to convert the near-field electromagnetic field to the far-field to generate the absolute TRP value. Such an anechoic chamber requires millions of dollars. For example, to test a product with a frequency of 650MHz, the anechoic chamber dimensions would be approximately (L*W*H): 1820*1700*1950mm, with a testing accuracy of approximately ±0.5dB. This process is lengthy and expensive, making it unsuitable for mass production testing. For mass production line testing, the primary method is to use a comparative gold-plating tester. First, the product undergoes TRP testing in a spherical multi-probe anechoic chamber. A gold-plating tester that meets the requirements is selected, placed in the mass production testing equipment to obtain a stable value. Then, the gold-plating tester is removed, and a mass-produced product is tested to obtain a new value. If the difference between this value and the gold-plating tester's value in the mass production testing equipment is within a specified range, the production requirements are met. Currently, there are three main mass production testing solutions on the market:

[0003] 1. Reverberation Chamber-like Solution: The test is conducted by placing a circularly polarized antenna coupling plate inside a metal shielded box. The test is usually performed in the near-field radiation region. Since the signal emitted by the test is continuously reflected inside the shielded box, and the antenna coupling plate and the test are strongly coupled, even a slight offset of the coupling plate can cause a large change in the test results, introducing test errors. This causes production personnel to spend a lot of time searching for and fixing the optimal position of the coupling plate, wasting a lot of manpower.

[0004] 2. Extremely Near Field Testing Scheme: This scheme primarily uses an electromagnetic field probe array to extract data from the device under test in the near-field region. Data acquisition is achieved by switching the probes on and off. However, since the near-field region mainly consists of induced fields, radiated fields, and surface waves, complex algorithms are required to eliminate interference field strength. Furthermore, the fixed position of the antenna array elements prevents modification of the spatial resolution and makes it impossible to replace the probes. Consequently, the receiving sensitivity can only be improved by adjusting the link signal-to-noise ratio, greatly reducing its applicability. It also suffers from issues related to positional accuracy leading to testing accuracy problems and poor high-frequency signal reception.

[0005] The basic principle of the two above schemes is that they require relative testing using a standard instrument. The final product value obtained from the test is close to that of the standard instrument. If you want to test the absolute TRP value of a product, in addition to a spherical multi-probe anechoic chamber, a mechanically stirred reverberation chamber can also be used for testing. However, this has disadvantages such as a construction cost in the millions, long testing time, and large space occupation (testing a 650MHz product requires a reverberation chamber with dimensions of approximately (L*W*H): 1600X2000x1800mm). In the process of product development or when problems occur in mass production, it is quite difficult for R&D or production lines to quickly obtain the absolute TRP value of a product. Summary of the Invention

[0006] To address the aforementioned problems, the present invention aims to provide a method for testing the absolute radiated power (TRP) of end products based on a source stirring reverberation test chamber. This method utilizes a production line source stirring reverberation test chamber to measure the absolute TRP value of the product. It employs a calibration method using a reference antenna and a virtual product to test both the virtual reference antenna and the end product, and processes the data through an algorithm. This overcomes the bottleneck of lacking a standard reference unit and enables the measurement of the absolute TRP value of the product. This facilitates product iteration and provides a reference for product manufacturing.

[0007] To achieve the above objectives, the solution of the present invention is as follows:

[0008] A method for testing the absolute radiated power of a terminal product based on a source stirring reverberation test chamber includes a source stirring reverberation test chamber, a signal generator, a signal receiving circuit, and a spectrum analyzer. A removable tray is provided within the shielded cavity of the test chamber, and multiple signal receiving antennas are arranged around the tray within the shielded cavity. The test steps of the method include:

[0009] S1. Place a reference antenna on the edge of the tray and in the center of the cavity. The reference antenna is connected to the signal generator through a cable. The signal generator transmits a signal through the reference antenna. The spectrum analyzer receives the signal from each signal receiving antenna through the signal receiving circuit.

[0010] S2. Perform statistical processing on the signals received from each receiving antenna to obtain the output power of the reference antenna, denoted as P. Ref ;

[0011] S3. Select a virtual reference antenna to replace the reference antenna on the edge of the tray and place it in the center of the cavity. The physical size of the virtual reference antenna is smaller than that of the reference antenna. The signal generator outputs a signal with the same power and transmits it through the virtual reference antenna. The spectrum analyzer receives the signals from each signal receiving antenna through the signal receiving circuit.

[0012] S4. Perform statistical processing on the signals received from each receiving antenna in S3 to obtain the output power of the virtual reference antenna, denoted as P. xrefBy covering the virtual reference antenna with absorbing or degrading material, the output power of the virtual reference antenna can be made equal to the output power of the reference antenna by increasing or decreasing the amount of absorbing or degrading material, i.e.: P xref =P Ref ;

[0013] S5. Replace the virtual reference antenna of the terminal product under test on the edge of the tray and place it in the center of the cavity. Control the terminal product under test to transmit signals. The spectrum analyzer receives the signals of each signal receiving antenna through the signal receiving circuit.

[0014] S6. Perform statistical processing on the signals received from each receiving antenna in S5 to obtain the transmit power of the tested terminal product, denoted as P. Dut ;

[0015] S7. Select a virtual terminal product antenna to replace the terminal product under test on the edge of the tray and place it in the center of the cavity. The virtual terminal product antenna is connected to the signal generator. The signal power value output by the signal generator to the virtual terminal product antenna port is the conducted power value of the terminal product under test. The spectrum analyzer receives the signal from each signal receiving antenna through the signal receiving circuit.

[0016] S8. Perform statistical processing on the signals received from each receiving antenna in S7 to obtain the output power of the virtual terminal product antenna, denoted as P. xDut By covering the antenna of the virtual terminal product with absorbing or damaging materials, and by increasing or decreasing the amount of absorbing or damaging materials, the output power of the virtual terminal product antenna is made equal to the transmission power of the received terminal product, i.e.: P xDutf =P Dut ;

[0017] S9. Remove the virtual terminal product and place the terminal product under test and the virtual reference antenna on the tray. The terminal product under test is placed on the edge of the tray and positioned at the center of the cavity. It transmits a signal. The virtual reference antenna is placed at a position one-quarter wavelength away from the test frequency band of the reference antenna and connected to a matching load. The spectrum analyzer receives signals from each signal receiving antenna through its signal receiving circuit. Statistical processing is performed on the received signals from each signal receiving antenna to obtain the combined power of the terminal product under test and the virtual reference antenna, denoted as P. RxDUT ;

[0018] S10. Remove the terminal product under test and the virtual reference antenna. Place the reference antenna and the virtual terminal product antenna on the tray, with the reference antenna positioned along the edge of the tray and at the center of the cavity. The reference antenna is connected to the signal generator to transmit signals. The virtual terminal product antenna is placed at a quarter-wavelength position relative to the test frequency band of the reference antenna and connected to a matching load. The spectrum analyzer receives signals from each signal receiving antenna through the signal receiving circuit. The received signals from each signal receiving antenna are statistically processed to obtain the combined power of the reference antenna and the virtual terminal product antenna, denoted as P. RxRef :

[0019] S11. Calculate the absolute TRP of the tested terminal product using the following formula. DUT value:

[0020] ;

[0021] Where: P RxDUT P represents the combined power value of the tested terminal product and the virtual reference antenna. RxRef The combined power value of the reference antenna and the virtual terminal product antenna; P in IL is the output signal power value of the signal generator. Ref For cable loss; For reference antenna efficiency.

[0022] A further aspect of the solution is that the signal receiving circuit is a switching matrix, and the spectrum analyzer receives the signals from each signal receiving antenna one by one through the switching matrix.

[0023] The solution further includes the following: the output power of the reference antenna, the output power of the virtual reference antenna, the transmission power of the terminal product under test, and the output power of the virtual terminal product antenna are obtained by statistically averaging the signals received by each signal receiving antenna.

[0024] A further aspect of the scheme is that the signal generator emits a signal with a test frequency band wavelength of 50mm-500mm via the reference antenna.

[0025] The solution further includes: the absorbing material is a polyurethane flat plate absorbing material, and the damaging material is a ferrite magnetic material.

[0026] A further aspect of the solution is that the multiple signal receiving antennas are arranged in a non-uniform layout around the tray in the shielding cavity, so that the field uniformity formed on the entire tray is less than 1dB in the range of 0.6-18GHz.

[0027] The solution further includes: both the reference antenna and the virtual reference antenna are designed as omnidirectional antennas using a rigid PCB, covering a frequency range of 0.6-18GHz, with a typical VSWR of 2.

[0028] The solution further specifies that the dimensions of the shielding cavity are 750mm long x 670mm wide x 450mm high.

[0029] The beneficial effects of this invention are: this invention eliminates the need to place the product in a standard darkroom for calibration testing, and allows for precise testing of TRP directly on the production line using a source stirring reverberation chamber, which facilitates rapid product iteration.

[0030] It has a small volume: the test chamber is only 1 / 25 the size of a mechanically stirred reverberation chamber.

[0031] The invention will be further explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0032] Figure 1 Schematic diagram of the source stirring reverberation test chamber;

[0033] Figure 2 Schematic diagram of the shielded cavity layout of the source stirring reverberation test chamber;

[0034] Figure 3 This is a schematic diagram of the measurement link in step S1;

[0035] Figure 4 This is a schematic diagram of the measurement link in step S3;

[0036] Figure 5 This is a schematic diagram of the measurement link in step S5;

[0037] Figure 6 This is a schematic diagram of the measurement link in step S7;

[0038] Figure 7 This is a schematic diagram of the measurement link in step S9;

[0039] Figure 8 This is a schematic diagram of the measurement link in step S10. Detailed Implementation

[0040] A method for testing the absolute radiated power of end products based on a source stirring reverberation test chamber, specifically for testing the absolute radiated power of 600MHz end products, see [link to relevant documentation]. Figures 1 to 8The method for testing the absolute radiated power of the terminal product includes a source stirring reverberation test chamber 1, a signal generator 2, a signal receiving circuit 3, and a spectrum analyzer 4. A removable tray 102 is provided in the shielded cavity 101 of the test chamber, and multiple signal receiving antennas 5 are arranged around the tray in the shielded cavity. The signal receiving circuit 3 is a switch matrix, and the spectrum analyzer receives the signal from each signal receiving antenna 5 one by one through a single-pole n-throw switch 301 in the switch matrix. The dimensions of the shielded cavity are 750mm long x 670mm wide x 450mm high, which is 1 / 20 of the mechanical stirring reverberation anechoic chamber.

[0041] The test steps of the test method include:

[0042] S1, such as Figure 3 As shown, a reference antenna is placed on the edge of the tray and at the center of the cavity plane. The reference antenna is connected to the signal generator 2 through the cable 6. The signal generator 2 transmits signals through the reference antenna. The spectrum analyzer 4 receives the signals from each signal receiving antenna through the signal receiving circuit 3.

[0043] S2. Perform statistical processing on the signals received from each receiving antenna to obtain the output power of the reference antenna, denoted as P. Ref ;

[0044] S3, such as Figure 4 As shown, a virtual reference antenna is selected to replace the reference antenna on the edge of the tray and placed at the center of the cavity plane. The physical size of the virtual reference antenna is smaller than that of the reference antenna. The signal generator outputs a signal with the same power and transmits it through the virtual reference antenna. The spectrum analyzer receives the signals from each signal receiving antenna through the signal receiving circuit.

[0045] S4. Perform statistical processing on the signals received from each receiving antenna in S3 to obtain the output power of the virtual reference antenna, denoted as P. xref By covering the virtual reference antenna with absorbing or degrading material, the output power of the virtual reference antenna can be made equal to the output power of the reference antenna by increasing or decreasing the amount of absorbing or degrading material, i.e.: P xref =P Ref ;

[0046] S5, such as Figure 5 As shown, the virtual reference antenna is replaced by the terminal product under test (e.g., mobile phone) on the edge of the tray and placed at the center of the cavity plane. The terminal product under test is controlled to transmit signals, and the spectrum analyzer receives the signals from each signal receiving antenna through the signal receiving circuit.

[0047] S6. Perform statistical processing on the signals received from each receiving antenna in S5 to obtain the transmit power of the tested terminal product, denoted as P. Dut ;

[0048] S7, such as Figure 6 As shown, a virtual terminal product antenna is selected to replace the terminal product under test on the edge of the tray and placed at the center of the cavity plane. The virtual terminal product antenna is connected to the signal generator. The signal power value output by the signal generator to the virtual terminal product antenna port is the conducted power value of the terminal product under test. The spectrum analyzer receives the signal from each signal receiving antenna through the signal receiving circuit.

[0049] The virtual terminal product antenna is a miniaturized omnidirectional antenna that can be used as a transmitting antenna for the terminal product. The antenna is designed to cover the frequency used by the terminal product and has a normal radiating volume that can be placed on a tray. Furthermore, the radiation pattern and efficiency of this antenna can be disregarded.

[0050] S8. Perform statistical processing on the signals received from each receiving antenna in S7 to obtain the output power of the virtual terminal product antenna, denoted as P. xDut By covering the antenna of the virtual terminal product with absorbing or damaging materials, and by increasing or decreasing the amount of absorbing or damaging materials, the output power of the virtual terminal product antenna is made equal to the transmission power of the received terminal product, i.e.: P xDutf =P Dut ;

[0051] S9. Retrieve the virtual terminal product, such as Figure 7 As shown, the terminal product under test (DUT) and the virtual reference antenna are placed on a tray, with the DUT positioned along the edge of the tray and at the center of the cavity plane. The DUT transmits a signal. The virtual reference antenna is positioned at a position one-quarter wavelength away from the test frequency band of the reference antenna, and is connected to a matched load. The spectrum analyzer receives signals from each receiving antenna through a signal receiving circuit. Statistical processing is performed on the received signals from each receiving antenna to obtain the combined power of the DUT and the virtual reference antenna, denoted as P. RxDUT ;

[0052] S10. Remove the terminal product under test and the virtual reference antenna, such as... Figure 8 As shown, the reference antenna and the virtual terminal product antenna are placed on the tray. The reference antenna is positioned along the edge of the tray and at the center of the cavity plane, and is connected to the signal generator to transmit signals. The virtual terminal product antenna is placed at a quarter-wavelength position of the test frequency band from the reference antenna and connected to a matching load. The spectrum analyzer receives signals from each signal receiving antenna through the signal receiving circuit. The received signals from each signal receiving antenna are statistically processed to obtain the combined power of the reference antenna and the virtual terminal product antenna, denoted as P. RxRef ;

[0053] For steps S9 and S10, according to the relevant provisions of CTIA's "Large-Size Wireless Equipment Air Interface Performance Test Scheme" (Version 1.2.1, February 2019), TRP (Total Radiated Power) measurement is performed in a reverberation chamber. All test products and reference antennas must be placed in the quiet zone of the reverberation chamber to ensure that the loading effect inside the chamber is the same for both the test product and the reference antenna, and that the physical distance meets the quarter-wavelength requirement for accurate TRP values. For traditional testing, if testing a 600MHz product, according to antenna principles, the terminal antenna design size needs to meet the quarter-wavelength resonance requirement for normal radiation. Ordinary antennas are 125mm in size. Although using an LC circuit can reduce the antenna volume through a matching circuit, both the reference antenna and the DUT are still relatively large. They need to meet the quarter-wavelength distance requirement when placed on the tray, which is not easy to achieve. This embodiment changes the traditional method by using a production line source stirring reverberation test chamber to measure the absolute TRP value of the product. To this end, it proposes to equate the loading effect of the virtual reference antenna with that of the reference antenna and the loading effect of the virtual terminal product antenna with that of the product DUT through the above method. By using absorbing and damaging materials, it can be miniaturized without having to pay attention to the antenna pattern characteristics. This can meet the following conditions in the CTIA standard for testing the absolute TRP in the reverberation chamber: 1. The products are a quarter wavelength apart, which can be achieved through miniaturization using an innovative method; 2. The product and the reference antenna are simultaneously in the reverberation chamber, and the loading effect is made consistent within the chamber through an innovative method, so as to ensure that the measured TRP value is accurate.

[0054] S11. Calculate the absolute TRP of the tested terminal product using the following formula. DUT value:

[0055] ;

[0056] Where: P RxDUT P represents the combined power value of the tested terminal product and the virtual reference antenna. RxRef The combined power value of the reference antenna and the virtual terminal product antenna; P in IL is the output signal power value of the signal generator. Ref For cable loss; For reference antenna efficiency.

[0057] After steps S2-S4 above, the virtual reference antenna replaces the loading effect of the reference antenna, enabling step S9 to test an accurate value. After steps S6-S8 above, the virtual terminal product antenna replaces the loading effect of the terminal product, enabling step S10 to test an accurate value.

[0058] Wherein: the output power of the reference antenna, the output power of the virtual reference antenna, the transmit power of the terminal product under test, and the output power of the antenna of the virtual terminal product are obtained by statistical averaging of the signals received by each signal receiving antenna.

[0059] In this embodiment, the signal generated by the signal generator has a test frequency band wavelength of 50mm-500mm via the reference antenna, which is determined according to the frequency used by the terminal product.

[0060] The absorbing material is a polyurethane flat plate absorbing material, and the loss material is a high-loss magnetic material, such as a ferrite magnetic material.

[0061] In this embodiment, the multiple signal receiving antennas are arranged in a non-uniform layout around the tray in the shielding cavity, so that the field uniformity formed on the entire tray is less than 1dB in the range of 0.6-18GHz.

[0062] The reference antenna and the virtual reference antenna are both designed as omnidirectional antennas using a rigid PCB, covering a frequency range of 0.6-18GHz, with a typical VSWR of 2.

[0063] The above-described embodiment of the terminal product absolute radiated power test method based on a source stirring reverberation test chamber adopts a source stirring reverberation chamber scheme. Inside the shielded box, multiple probes (usually 15 / 24 / 32 antennas) are used for reception. The probes are switched via switches, and the received data is processed by statistical algorithms to create stable field uniformity in the test area. The antenna arrangement and distance are basically in the near-field radiation region. Only a small shielded box is needed (for testing 600MHz products, the shielded box size is approximately (L*W*H): 750mm x 670mm x 450mm) with reasonable design of probes and links to obtain a stable absolute TRP (Total Radiated Power) value. Moreover, this scheme is not sensitive to the product location and has the advantages of high accuracy and stability.

Claims

1. A method for testing the absolute radiated power of an end product based on a source stirring reverberation test chamber, comprising a source stirring reverberation test chamber, a signal generator, a signal receiving circuit, and a spectrum analyzer; a removable tray is disposed in the center of the shielded cavity of the test chamber, and multiple signal receiving antennas are arranged around the tray within the shielded cavity, characterized in that, The test steps of the test method include: S1. Place a reference antenna on the edge of the tray and in the center of the cavity. The reference antenna is connected to the signal generator through a cable. The signal generator transmits a signal through the reference antenna. The spectrum analyzer receives the signal from each signal receiving antenna through the signal receiving circuit. S2. Perform statistical processing on the signals received from each receiving antenna to obtain the output power of the reference antenna, denoted as P. Ref ; S3. Select a virtual reference antenna to replace the reference antenna on the edge of the tray and place it in the center of the cavity. The physical size of the virtual reference antenna is smaller than that of the reference antenna. The signal generator outputs a signal with the same power and transmits it through the virtual reference antenna. The spectrum analyzer receives the signals from each signal receiving antenna through the signal receiving circuit. S4. Perform statistical processing on the signals received from each receiving antenna in S3 to obtain the output power of the virtual reference antenna, denoted as P. xref By covering the virtual reference antenna with absorbing or degrading material, the output power of the virtual reference antenna can be made equal to the output power of the reference antenna by increasing or decreasing the amount of absorbing or degrading material, i.e.: P xref =P Ref ; S5. Replace the virtual reference antenna of the terminal product under test on the edge of the tray and place it in the center of the cavity. Control the terminal product under test to transmit signals. The spectrum analyzer receives the signals of each signal receiving antenna through the signal receiving circuit. S6. Perform statistical processing on the signals received from each receiving antenna in S5 to obtain the transmit power of the tested terminal product, denoted as P. Dut ; S7. Select a virtual terminal product antenna to replace the terminal product under test on the edge of the tray and place it in the center of the cavity. The virtual terminal product antenna is connected to the signal generator. The signal power value output by the signal generator to the virtual terminal product antenna port is the conducted power value of the terminal product under test. The spectrum analyzer receives the signal from each signal receiving antenna through the signal receiving circuit. S8. Perform statistical processing on the signals received from each receiving antenna in S7 to obtain the output power of the virtual terminal product antenna, denoted as P. xDut By covering the antenna of the virtual terminal product with absorbing or damaging materials, and by increasing or decreasing the amount of absorbing or damaging materials, the output power of the virtual terminal product antenna is made equal to the transmission power of the received terminal product, i.e.: P xDutf =P Dut ; S9. Remove the virtual terminal product and place the terminal product under test and the virtual reference antenna on the tray. The terminal product under test is placed on the edge of the tray and positioned at the center of the cavity. It transmits a signal. The virtual reference antenna is placed at a position one-quarter wavelength away from the test frequency band of the reference antenna and connected to a matching load. The spectrum analyzer receives signals from each signal receiving antenna through its signal receiving circuit. Statistical processing is performed on the received signals from each signal receiving antenna to obtain the combined power of the terminal product under test and the virtual reference antenna, denoted as P. RxDUT ; S10. Remove the terminal product under test and the virtual reference antenna. Place the reference antenna and the virtual terminal product antenna on the tray, with the reference antenna positioned along the edge of the tray and at the center of the cavity. The reference antenna is connected to the signal generator to transmit signals. The virtual terminal product antenna is placed at a quarter-wavelength position relative to the test frequency band of the reference antenna and connected to a matching load. The spectrum analyzer receives signals from each signal receiving antenna through the signal receiving circuit. The received signals from each signal receiving antenna are statistically processed to obtain the combined power of the reference antenna and the virtual terminal product antenna, denoted as P. RxRef : S11. Calculate the absolute TRP of the tested terminal product using the following formula. DUT value: ； Where: P RxDUT P represents the combined power value of the tested terminal product and the virtual reference antenna. RxRef The combined power value of the reference antenna and the virtual terminal product antenna; P in IL is the output signal power value of the signal generator. Ref For cable loss; For reference antenna efficiency.

2. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The signal receiving circuit is a switching matrix, and the spectrum analyzer receives the signals from each signal receiving antenna one by one through the switching matrix.

3. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The output power of the reference antenna, the output power of the virtual reference antenna, the transmit power of the terminal product under test, and the output power of the virtual terminal product antenna are obtained by statistical averaging of the signals received by each signal receiving antenna.

4. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The signal generator emits a signal with a test frequency band wavelength of 50mm-500mm via the reference antenna.

5. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The absorbing material is a polyurethane flat plate absorbing material, and the damaging material is a ferrite magnetic material.

6. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The multiple signal receiving antennas are arranged in a non-uniform layout around the tray in the shielded cavity, so that the field uniformity formed on the entire tray is less than 1dB in the range of 0.6-18GHz.

7. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, Both the reference antenna and the virtual reference antenna are designed as omnidirectional antennas using a rigid PCB, covering a frequency range of 0.6-18GHz, with a typical VSWR of 2.

8. The method for testing the absolute radiated power of a terminal product according to claim 1, characterized in that, The dimensions of the shielding cavity are 750mm long x 670mm wide x 450mm high.

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