CN103051392B - Method and device for intermodulation interference test of wireless communication terminal of private network - Google Patents

Abstract

The embodiment of the present invention provides a method and a device for intermodulation interference testing of private network wireless communication terminals. The method mainly includes: according to the test specification requirements of the intermodulation interference test of the private network wireless communication terminal, selecting and connecting a circulator from the circulator group through the coaxial switch, and/or; selecting from the attenuator group through the coaxial switch Select to connect an attenuator; the circulator group is connected to the attenuator group, and the circulator group receives the input measured signal of the private network wireless communication terminal, and uses the connected circulator and/or attenuator to process the measured signal and attenuate the signal. The detector group outputs the processed signal under test. The embodiment of the present invention overcomes the problem that different test links need to be manually built for different test specifications during the intermodulation interference test process of the private network wireless communication terminal, and realizes all models of the private network wireless communication terminal. System integration of test links for spurious indicators.

Description

Method and device for intermodulation interference test on private network wireless communication terminal

technical field

The invention relates to the technical field of private network wireless communication terminal testing, in particular to a method and device for intermodulation interference testing of private network wireless communication terminals.

Background technique

The private network terminal radio frequency automatic test system refers to the automated test system that uses computer control to automatically complete call establishment, link switching, signal measurement, data calculation and processing, and output test results. It is mainly used for radio frequency index testing and Automatic test system construction, including radio frequency index test of private network wireless communication terminals such as digital walkie-talkie, digital trunking, digital radio, analog walkie-talkie and automatic test system tower construction.

At present, in the process of intermodulation interference test for private network model approval for private network wireless communication terminals, for different intermodulation interference test items and standards, it is necessary to manually install corresponding radio frequency links to meet the test requirements. Sometimes, in In the process of completing an intermodulation interference test, multiple test links need to be carried manually. This test method is not only inefficient, but also manually carries test links, which will introduce measurement errors and affect the accuracy of test results.

Contents of the invention

Embodiments of the present invention provide a method and device for intermodulation interference testing on private network wireless communication terminals, so as to effectively perform intermodulation interference testing on private network wireless communication terminals.

A method for performing intermodulation interference testing on private network wireless communication terminals, comprising:

According to the test specification requirements of the intermodulation interference test of the private network wireless communication terminal, select and connect a circulator from the circulator group through the coaxial switch, and/or; select and connect an attenuator from the attenuator group through the coaxial switch The circulator group includes a plurality of different types of circulators connected in parallel, the attenuator group includes a plurality of different types of attenuators connected in parallel, and the circulator group is connected to the attenuator group;

The circulator group receives the input measured signal of the private network wireless communication terminal, the measured signal passes through the circulator group and the attenuator group in turn, and the connected circulator and/or attenuator are used to control the measured signal. The measured signal is processed, and the attenuator group outputs the processed measured signal.

A device for performing an intermodulation interference test on a private network wireless communication terminal, comprising:

A circulator group, an attenuator group, a first coaxial switch connected to the circulator group, a second coaxial switch connected to the attenuator group, and the circulator group connected to the attenuator group;

According to the test specification requirements of the intermodulation interference test of private network wireless communication terminals, select and connect a circulator from the circulator group through the first coaxial switch, and/or; through the second coaxial switch from the attenuation Select an attenuator in the group;

The circulator group receives the input measured signal of the private network wireless communication terminal, and the measured signal passes through the circulator group and the attenuator group in turn, and the connected circulators and/or the connected circulators in the circulator group The attenuator connected in the attenuator group processes the signal under test, and the amplifier group outputs the signal under test processed by the device.

It can be seen from the above-mentioned technical solutions provided by the embodiments of the present invention that the device for performing intermodulation interference testing on private network wireless communication terminals provided by the embodiments of the present invention is a compact professional private network model-approved intermodulation interference tester The comprehensive solution is suitable for the application of the automatic test system in the field of private network type approval intermodulation interference test design verification and automatic test. It overcomes the problem of manually building different test links for different test specifications during the intermodulation interference test process of private network wireless communication terminals, and realizes the system integration of all intermodulation interference test links for private network wireless communication terminals.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without any creative effort.

FIG. 1 is a structural diagram of a device for performing an intermodulation interference test on a private network wireless communication terminal provided by Embodiment 1 of the present invention;

Fig. 2 is a schematic diagram of connection of four circulators and a coaxial switch provided in Embodiment 1 of the present invention;

FIG. 3 is a schematic diagram of the connection of two attenuators and a coaxial switch provided in Embodiment 1 of the present invention;

FIG. 4 is a specific structural diagram of a device for performing an intermodulation interference test on a private network wireless communication terminal provided by Embodiment 1 of the present invention when the above-mentioned 4 circulators and 2 attenuators are used;

5 is a processing flowchart of a method for performing an intermodulation interference test on a private network wireless communication terminal provided by Embodiment 2 of the present invention;

FIG. 6 is a schematic diagram of a test principle of intermodulation interference for private network wireless communication terminals provided by an embodiment provided by Embodiment 2 of the present invention.

Detailed ways

In order to facilitate the understanding of the embodiments of the present invention, several specific embodiments will be taken as examples for further explanation below in conjunction with the accompanying drawings, and each embodiment does not constitute a limitation to the embodiments of the present invention.

Embodiment one

A structural diagram of a device for performing an intermodulation interference test on a private network wireless communication terminal provided in this embodiment is shown in FIG. 1 , including the following modules:

A circulator group 11 and an attenuator group 12 , and a first coaxial switch 13 connected to the circulator group 11 , and a second coaxial switch 14 connected to the attenuator group 12 . The group of circulators 11 is connected to the group of attenuators 12 . The circulator group 11 receives the input signal under test of the private network wireless communication terminal, and the attenuator group 12 outputs the signal under test after being processed by the device.

The above-mentioned circulator group 11 includes a plurality of different types of circulators connected in parallel, the coaxial switch 13 is connected to each circulator in the circulator group 11, and the circulators are controlled by the first coaxial switch. Each circulator in the circulator group 11 is turned on and off. During a test, the first coaxial switch 13 only turns on one circulator or turns off all the circulators.

The aforementioned attenuator group 12 includes a plurality of different types of attenuators connected in parallel, and the second coaxial switch 14 is connected to each attenuator in the attenuator group 12, and is controlled by the second coaxial switch 14. Each attenuator in the attenuator group 12 is turned on and off. During a test, the second coaxial switch 14 only turns on one attenuator or turns off all the attenuators.

The aforementioned circulators of different types may include: 137-167MHz circulators, 351-389MHz circulators, 403-423.5MHz circulators and 806-866MHz circulators.

The circulator is a multi-port device. The transmission of the signal in the circulator can only circulate in one direction. In modern radar and microwave multi-channel communication systems, devices with unidirectional circulation characteristics are used. In the intermodulation interference test process of wireless communication terminals in private networks, signals of different frequencies can be separated by using a circulator.

The connection schematic diagram of the above four circulators and the coaxial switch is shown in FIG. 2 . The above-mentioned 137-167MHz circulator can loop through the tested signal whose operating frequency is between 137-167MHz. The above-mentioned 351-389MHz circulator can loop through the tested signal whose operating frequency is between 351-389MHz. The above-mentioned 403-423.5MHz circulator can loop through the tested signal whose operating frequency is between 403-423.5MHz. The above-mentioned 806-866MHz circulator can loop through the tested signal whose operating frequency is between 806-866MHz.

The aforementioned attenuators of different types include: a 10dB high-power attenuator and a 20dB high-power attenuator. The function of the high-power attenuator is to reduce the energy of the measured signal processed by the circulator, so as to protect the subsequent test instruments and meet the test requirements.

The connection diagram of the above two attenuators and the coaxial switch is shown in Figure 3. The above-mentioned 10dB high-power attenuator is used to attenuate the power in the signal under test by 10dB, and the above-mentioned 20dB high-power attenuator is used for attenuating the power in the signal under test by 20dB.

When the above-mentioned 4 circulators and 2 attenuators are used, the specific structural diagram of the device for intermodulation interference testing of private network wireless communication terminals according to the embodiment of the present invention is shown in Figure 4. The whole device adopts a standard 4U chassis, 4U The chassis refers to the height of the chassis: 1U=44.5mm, 4U=178mm, the front of the box is provided with an antenna interface, which is mainly used to connect the receiving antenna. The receiving antenna inputs the received signal of the private network wireless communication terminal into the above-mentioned device for intermodulation interference testing of the private network wireless communication terminal, and the above-mentioned measured signal passes through the circulator group and the attenuator group in the device in turn, The circulator and/or attenuator connected by the coaxial switch performs corresponding loop-through and attenuation processing on the above-mentioned measured signal. There is an output interface at the rear of the box, through which the tested signal processed by the above device is sent to the test instrument, and the intermodulation interference test for private network model approval is carried out.

The performance parameters, service life and installation method of each module in the above device can not only meet the relevant requirements of the intermodulation attenuation test of private network equipment, but also provide necessary protection for the test instrument to avoid overheating RF power, DC transient and static electricity. damaged by discharge.

Embodiment two

Based on the device shown in FIG. 1 above, the processing flow of a method for performing an intermodulation interference test on a private network wireless communication terminal provided by this embodiment is shown in FIG. 5 , including the following processing flow:

Step 51, forming a circulator group by using multiple circulators, and forming an attenuator group by multiple attenuators.

A plurality of different types of circulators are connected in parallel to form a circulator group, and the first coaxial switch is connected to each circulator in the circulator group, and each circulator is controlled by the first coaxial switch. Turning on and off, during a test, the first coaxial switch only turns on one circulator or turns off all circulators;

A plurality of attenuators of different types are connected in parallel to form an attenuator group, a second coaxial switch is connected to each attenuator in the attenuator group, and each attenuator is controlled by the second coaxial switch. On and off, during a test, the second coaxial switch only turns on one attenuator or turns off all attenuators.

The set of circulators is connected to the set of attenuators.

The multiple different types of circulators include: 137-167MHz circulators, 351-389MHz circulators, 403-423.5MHz circulators and 806-866MHz circulators;

The multiple attenuators of different models include: a 10dB high-power attenuator and a 20dB high-power attenuator.

Step 52. According to the test specification requirements of the intermodulation interference test of the private network wireless communication terminal, select and connect a circulator from the circulator group through the coaxial switch, and/or; select and connect a circulator from the attenuator group through the coaxial switch through an attenuator.

Different circulators are selected according to the operating frequency of the private network wireless communication terminal, and the operating frequency of the private network wireless communication terminal should be between the operating frequencies of the circulator. The circulators with different bandwidths used in the embodiment of the present invention cover all test items of the private network type approval intermodulation interference test, and can flexibly switch the circulator links used in the test process of each index.

When the private network wireless communication terminal is a private network private network wireless communication terminal, the comparison schematic table of the equipment operating frequency band, circulator group, and selected circulator for the intermodulation interference test of the private network wireless communication terminal is shown in Table 1 below. Show,

Table 1

Only when the working frequency of the device is within the working frequency range of the selected circulator can the selected circulator be triggered to work.

Step 53: Process the signal under test of the private network wireless communication terminal by using the circulator and/or the attenuator that are selectively turned on.

The above-mentioned circulator group receives the input measured signal of the private network wireless communication terminal, and the measured signal passes through the circulator group and the attenuator group in turn, and the attenuator group outputs the measured signal processed by the device.

The above-mentioned measured signal passes through the circulator group and the attenuator group in the device in turn, and the circulator and/or attenuator connected by the coaxial switch performs corresponding circular passing and attenuation processing on the above-mentioned measured signal. There is an instrument interface at the rear of the box, through which the measured signal processed by the above-mentioned device is sent to the test instrument, and the test of different standards of radiation spurious for model approval is carried out.

A schematic diagram of a test principle of intermodulation interference for private network wireless communication terminals provided by this embodiment is shown in FIG. 6 , and a 20db fixed attenuator is respectively connected before and after the circulator.

Connect the test system according to the connection method shown in Figure 6. The measurement equipment is a spectrum analyzer with an effective value detection method. The insertion loss of the circulator is less than 1dB and the isolation is greater than 20dB. The test procedure is as follows:

a) The working frequency of the private network wireless communication terminal is the intermediate frequency, the transmitter continuously transmits the non-modulated signal at the maximum power, and the internal attenuator and frequency span of the spectrum analyzer, select the appropriate value to ensure that the spectrum analyzer works in a linear dynamic range and the spectrum analyzer can accurately measure intermodulation products to the greatest extent;

b) The frequency of the interference signal source is set to be 100kHz higher than the center frequency of the private network wireless communication terminal, and the output power and signal type of the interference signal source are set to be the same as those of the transmitter under test.

c) The interference signal and equipment working signal enter the spectrum analyzer through the circulator, and directly read the difference between the third-order intermodulation product and the main signal, that is, the value of the intermodulation attenuation;

Adjust the frequency of the interference signal source to be 100kHz lower than the center frequency of the private network wireless communication terminal, and repeat the test process from b) to c).

The above private network wireless communication terminal can be: FM base station, FM handheld station, FM vehicle station, FM coast station, FM ship station, public walkie-talkie, digital walkie-talkie system base station, digital walkie-talkie system transponder, digital walkie-talkie system handheld station, digital walkie-talkie System vehicle station, digital walkie-talkie system coastal station, digital walkie-talkie system ship station, short-wave SSB station, digital transmission station, aviation station, AM navigation station, centerless system handheld station, centerless system vehicle station, centerless system transponder , Centerless System Monitoring Station, Digital Centerless System Handheld Station, Digital Centerless System Vehicle Station, Digital Centerless System Transponder, Digital Centerless System Monitoring Station, GSM-R Railway Special Mobile Phone, GSM-R Railway Special Vehicle Mobile phone, GSM-R railway dedicated fixed telephone, GSM-R railway dedicated terminal, analog trunking base station, analog trunking handheld station, analog trunking vehicle station, analog trunking data terminal, digital trunking iDEN base station, digital trunking iDEN handheld station, etc. .

Those skilled in the art can understand that the accompanying drawing is only a schematic diagram of an embodiment, and the modules or processes in the accompanying drawing are not necessarily necessary for implementing the present invention.

The specific process of the method of using the method of the embodiment of the present invention to test the intermodulation interference of the private network wireless communication terminal is similar to the foregoing device embodiment, and will not be repeated here.

In the process of completing an intermodulation interference test, multiple test links need to be carried manually. This test method is not only inefficient, but also manually carries test links, which will introduce measurement errors and affect the accuracy of test results.

To sum up, the device for intermodulation interference testing of private network wireless communication terminals provided by the embodiment of the present invention is a compact and professional private network model-approved intermodulation interference test comprehensive solution, suitable for private network model-approved mutual The application of automatic test system in terms of tuning interference test design verification and automatic test. It overcomes the problem of manually building different test links for different test specifications during the intermodulation interference test process of private network wireless communication terminals, and realizes the system integration of all intermodulation interference test links for private network wireless communication terminals.

The embodiments of the present invention improve the test accuracy and test efficiency of the intermodulation interference test of the private network wireless communication terminal, and at the same time protect the instrument from being damaged due to overheated radio frequency power, DC transient and electrostatic discharge.

The embodiment of the present invention upgrades the test of manual switching circulator components to the stage of automatic switching test, improves test efficiency, reduces human errors, and also lays a foundation for the development of radiation disturbance and radiation spurious indicators in future automatic test systems. It provides a good reference for more complex automated testing in the future.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed in the present invention can easily think of changes or Replacement should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (4)

1. A method for intermodulation interference testing of private network wireless communication terminals, characterized in that, comprising: A plurality of different types of circulators are connected in parallel to form a circulator group, and the first coaxial switch is connected to each circulator in the circulator group, and each circulator is controlled by the first coaxial switch. Turn on and off, connect multiple attenuators of different types in parallel to form an attenuator group, connect the second coaxial switch to each attenuator in the attenuator group, and control it through the second coaxial switch To turn on and off each attenuator, in a test process, according to the test specification requirements of the intermodulation interference test of the private network wireless communication terminal, select and turn on a ring from the circulator group through the first coaxial switch or disconnect all the circulators, connect one attenuator from the attenuator group through the second coaxial switch or disconnect all the attenuators; The multiple different types of circulators include: 137-167MHz circulators, 351-389MHz circulators, 403-423.5MHz circulators and 806-866MHz circulators; the 137-167MHz circulators work at a frequency of 137-167MHz The measured signal between the 351-389MHz circulator loops through the measured signal with an operating frequency between 351-389MHz, and the 403-423.5MHz circulator performs a loop through the operating frequency between 403-423.5MHz The measured signal between the 806-866MHz circulator is looped through the measured signal with the working frequency between 806-866MHz; the working frequency of the private network wireless communication terminal is within the selected circulator The selected circulator can only be triggered within the working frequency range; The multiple different types of attenuators include: 10dB high-power attenuator, 20dB high-power attenuator; The circulator group receives the input measured signal of the private network wireless communication terminal, the measured signal passes through the circulator group and the attenuator group in turn, and the connected circulator and/or attenuator are used to control the measured signal. The measured signal is processed, and the attenuator group outputs the processed measured signal. 2. the method for carrying out intermodulation interference test to private network wireless communication terminal according to claim 1, is characterized in that, described method specifically comprises: The comparison schematic table of the equipment operating frequency band, circulator group, and selected circulator for the intermodulation interference test of the private network wireless communication terminal is shown in the following table 1, Table 1 Only when the working frequency of the device is within the working frequency range of the selected circulator can the selected circulator be triggered to work. 3. A device for intermodulation interference testing of private network wireless communication terminals, characterized in that it comprises: A circulator group, an attenuator group, a first coaxial switch connected to the circulator group, a second coaxial switch connected to the attenuator group, the circulator group connected to the attenuator group, and The circulator group includes multiple circulators of different types connected in parallel, the first coaxial switch is connected to each circulator in the circulator group, and the first coaxial switch controls the circulator group Each circulator is turned on and off, the attenuator group includes a plurality of different types of attenuators connected in parallel, and the second coaxial switch is connected to each attenuator in the attenuator group , the second coaxial switch controls on and off of each attenuator in the attenuator group; The multiple different types of circulators include: 137-167MHz circulators, 351-389MHz circulators, 403-423.5MHz circulators and 806-866MHz circulators; the 137-167MHz circulators work at a frequency of 137-167MHz The measured signal between the 351-389MHz circulator loops through the measured signal with an operating frequency between 351-389MHz, and the 403-423.5MHz circulator performs a loop through the operating frequency between 403-423.5MHz The measured signal between the 806-866MHz circulator is looped through the measured signal with the working frequency between 806-866MHz; the working frequency of the private network wireless communication terminal is within the selected circulator The selected circulator can only be triggered within the working frequency range; The multiple different types of attenuators include: 10dB high-power attenuator, 20dB high-power attenuator; According to the test specification requirements of the intermodulation interference test of the private network wireless communication terminal, in a test process, select a circulator from the circulator group through the first coaxial switch or turn on all circulators disconnecting, selecting one attenuator from the attenuator group through the second coaxial switch or disconnecting all attenuators; The circulator group receives the input measured signal of the private network wireless communication terminal, and the measured signal passes through the circulator group and the attenuator group in turn, and the connected circulators and/or the connected circulators in the circulator group The attenuators connected in the attenuator group process the signal under test, and the attenuator group outputs the signal under test processed by the device. 4. The device for performing intermodulation interference test on a private network wireless communication terminal according to claim 3, wherein the device is provided with an antenna interface and an output interface, and the antenna interface is connected to a receiving antenna to receive input The signal under test of the private network wireless communication terminal, the output interface outputs the signal under test processed by the device.