CN111010247A - Electromagnetic interference test system and method for radio system - Google Patents
Electromagnetic interference test system and method for radio system Download PDFInfo
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- CN111010247A CN111010247A CN201911343217.1A CN201911343217A CN111010247A CN 111010247 A CN111010247 A CN 111010247A CN 201911343217 A CN201911343217 A CN 201911343217A CN 111010247 A CN111010247 A CN 111010247A
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/30—Monitoring; Testing of propagation channels
- H04B17/309—Measuring or estimating channel quality parameters
- H04B17/345—Interference values
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B17/00—Monitoring; Testing
- H04B17/30—Monitoring; Testing of propagation channels
- H04B17/391—Modelling the propagation channel
- H04B17/3912—Simulation models, e.g. distribution of spectral power density or received signal strength indicator [RSSI] for a given geographic region
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Abstract
The invention discloses an electromagnetic interference test system of a radio system, which is arranged in a semi-anechoic chamber and comprises: the system comprises an amplitude modulation transmitter, a frequency modulation transmitter, a receiver, a first transmitting antenna, a second transmitting antenna and a receiving antenna; the first transmitting antenna is connected with the amplitude modulation transmitter, the second transmitting antenna is connected with the frequency modulation transmitter, and the receiving antenna is connected with the receiver; the amplitude modulation transmitter is in communication connection with the receiver through a first transmitting antenna and a receiving antenna, and the frequency modulation transmitter is in communication connection with the receiver through a second transmitting antenna and a receiving antenna; the receiving antenna is arranged at a position where the vertical distance between the amplitude modulation transmitter and the frequency modulation transmitter is a second preset distance. The invention also discloses a method for testing the electromagnetic interference of the radio system, which can effectively eliminate other electromagnetic interference in the space and reduce the hardware requirement of the testing equipment, thereby effectively reducing the testing difficulty and improving the accuracy of the testing result.
Description
Technical Field
The present invention relates to the field of wireless communication technologies, and in particular, to a system and a method for testing electromagnetic interference of a radio system.
Background
With the rapid development of information-based construction, different electromagnetic interference can be caused among radio equipment, and the radio equipment develops towards intellectualization, integration and complication, so that the problem of the caused electromagnetic interference is very serious; modulation is important in radio communications and the problem of electromagnetic interference between transmitting devices of different modulations is investigated. At present, a test scheme of a transmitting system is complex, a plurality of test devices are used, electromagnetic interference in a wireless communication system is various, so that the test difficulty is high, and the uncertainty of a test result is high.
Disclosure of Invention
The embodiment of the invention provides a system and a method for testing electromagnetic interference of a radio system, which can effectively eliminate other electromagnetic interference in space and reduce the computational complexity and hardware requirements of testing equipment, thereby effectively reducing the testing difficulty and improving the accuracy of a testing result.
An embodiment of the present invention provides an electromagnetic interference testing system for a radio system, which is installed in a semi-anechoic chamber, and includes: the system comprises an amplitude modulation transmitter, a frequency modulation transmitter, a receiver, a first transmitting antenna, a second transmitting antenna and a receiving antenna;
the first transmitting antenna is connected with the amplitude modulation transmitter, the second transmitting antenna is connected with the frequency modulation transmitter, and the receiving antenna is connected with the receiver;
the amplitude modulation transmitter is in communication connection with the receiver through the first transmitting antenna and the receiving antenna, and the frequency modulation transmitter is in communication connection with the receiver through the second transmitting antenna and the receiving antenna;
the receiving antenna is arranged at a position where the vertical distance between the amplitude modulation transmitter and the frequency modulation transmitter is a second preset distance.
As a modification of the above, the first preset distance is 0.2m to 0.5 m.
As a modification of the above, the second preset distance is 1 m.
As an improvement of the above solution, the receiver is a radio with fm reception.
Another embodiment of the present invention correspondingly provides a method for testing electromagnetic interference of a radio system, which is suitable for the above-mentioned system for testing electromagnetic interference of a radio system, and the method includes the steps of:
receiving a first signal transmitted by an amplitude modulation transmitter and a third signal generated by a second signal transmitted by the frequency modulation transmitter through a receiving antenna in a preset receiving frequency band; the first signal is transmitted by the amplitude modulation transmitter through a first transmitting antenna according to a preset first working frequency point, and the second signal is transmitted by the amplitude modulation transmitter through a second transmitting antenna according to a preset second working frequency point;
and analyzing the frequency point and the signal intensity corresponding to the third signal, and determining the frequency point and the interference value of the electromagnetic interference generated by the radio system.
As an improvement of the above scheme, the first operating frequency point and the second operating frequency point are different.
As an improvement of the above solution, before the receiving, by the receiving antenna, the first signal transmitted by the am transmitter and the second signal transmitted by the fm transmitter in the preset receiving frequency band, the method further includes:
determining a main working frequency point, transmitting power and a communication distance of an amplitude modulation transmitter, and setting a first working frequency point of the amplitude modulation transmitter;
the method comprises the steps of determining a main working frequency point, transmitting power and a communication distance of a frequency modulation transmitter, and setting a second working frequency point of the frequency modulation transmitter.
As an improvement of the above solution, before the receiving, by the receiving antenna, the first signal transmitted by the am transmitter and the second signal transmitted by the fm transmitter in the preset receiving frequency band, the method further includes:
presetting a receiving frequency band of a receiver;
and selecting a corresponding receiving antenna according to the receiving frequency band of the receiver.
Compared with the prior art, the electromagnetic interference test system and the method for the radio system disclosed by the embodiment of the invention have the advantages that a first signal is sent to a receiver through a first transmitting antenna according to a preset first working frequency point by an amplitude modulation transmitter, a second signal is sent to the receiver through a second transmitting antenna according to a preset second working frequency point by a frequency modulation transmitter, then the receiver receives a third signal generated by the first signal and the second signal through a receiving antenna in a preset receiving frequency band, and then the frequency point and the signal intensity corresponding to the third signal are analyzed, and the frequency point and the interference value of the electromagnetic interference generated by the radio system are determined, so that the electromagnetic interference existing in the radio communication system can be determined by analyzing the electromagnetic environment between the amplitude modulation transmitter and the frequency modulation transmitter, and the electromagnetic interference environment based on the amplitude modulation and the frequency modulation communication system can be better simulated, the simulation of the electromagnetic interference environment is realized by adopting a small amount of equipment instruments, the test scheme is simple, the operation is simple and convenient, and the calculation complexity of the test is effectively reduced, so that the hardware requirement of the test equipment is reduced. Meanwhile, the electromagnetic interference test system of the radio system is arranged in a semi-anechoic chamber, and other electromagnetic interference in the space can be effectively eliminated, so that the test difficulty can be effectively reduced, the contact degree of the simulation test is improved, and the accuracy of the test result is improved.
Drawings
Fig. 1 is a schematic structural diagram of an electromagnetic interference testing system of a radio system according to an embodiment of the present invention;
fig. 2 is a schematic flowchart of a method for testing electromagnetic interference of a radio system according to a second embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example one
Fig. 1 is a schematic structural diagram of an electromagnetic interference testing system of a radio system according to an embodiment of the present invention, including:
is installed in a semi-anechoic chamber and comprises: an amplitude modulation transmitter 11, a frequency modulation transmitter 12, a receiver 13, a first transmitting antenna 14, a second transmitting antenna 15 and a receiving antenna 16;
the first transmitting antenna 14 is connected to the am transmitter 11, the second transmitting antenna 15 is connected to the fm transmitter 12, and the receiving antenna 16 is connected to the receiver 13;
the AM transmitter 11 is connected with the receiver 13 through the first transmitting antenna 14 and the receiving antenna 16, and the FM transmitter 12 is connected with the receiver 13 through the second transmitting antenna 15 and the receiving antenna 16;
the am transmitter 11 is installed at a first preset distance from the fm transmitter 12, and the receiving antenna 16 is installed at a second preset distance from the am transmitter 11 to the fm transmitter 12.
Preferably, the first preset distance d1 is 0.2m to 0.5 m.
Preferably, the second preset distance d2 is 1 m.
Preferably, the receiver 13 is a radio with fm reception.
In this embodiment, the half anechoic chamber is similar to the full anechoic chamber in that it is a six-sided box with a shielding design, and the inside of the box is covered with an electromagnetic wave absorbing material. But the difference is that the semi-anechoic chamber uses a conductive floor and is not covered with wave-absorbing materials. The semi-anechoic chamber simulates the ideal open field situation, i.e. the field has an infinitely large, well conducting ground plane. In the semi-anechoic chamber, because the ground is not covered with the wave-absorbing material, a reflection path is generated, so that the signal received by the receiving antenna is the sum of the signals of the direct path and the reflection path, the electromagnetic interference in the external environment is isolated, and other electromagnetic interference existing in the space is eliminated.
It should be noted that the amplitude modulation transmitter 11 serves as a transmitting device for transmitting signals through the first transmitting antenna 14. The fm transmitter 12 serves as a transmitting device for transmitting signals through the second transmitting antenna 15. The receiver 13 is used as a receiving device for receiving signals through the receiving antenna 16, so as to form a wireless communication network for electrical interference test with the transmitting device, and a small amount of equipment instruments are adopted to realize the simulation of electromagnetic interference environment, so that the test scheme is simple, the operation is simple and convenient, and the hardware requirement of the test device is reduced. Illustratively, the distance d1 between the AM transmitter and the FM transmitter is 0.2m-0.5m, and the vertical distance d2 between the receiving antenna and the AM transmitter and the FM transmitter is 1 m.
The electromagnetic interference test system of the radio system provided by the embodiment of the invention is characterized in that an amplitude modulation transmitter, a frequency modulation transmitter, a receiver, a first transmitting antenna, a second transmitting antenna and a receiving antenna are arranged, the amplitude modulation transmitter transmits a first signal to the receiver through the first transmitting antenna according to a preset first working frequency point, the frequency modulation transmitter transmits a second signal to the receiver through the second transmitting antenna according to a preset second working frequency point, the receiver receives a third signal generated by the first signal and the second signal through the receiving antenna in a preset receiving frequency band, and then the frequency point and the signal intensity corresponding to the third signal are analyzed, the frequency point and the interference value of the electromagnetic interference generated by a radio system are determined, so the electromagnetic interference existing in the radio communication system can be determined by analyzing the electromagnetic environment between the amplitude modulation transmitter and the frequency modulation transmitter, the method is favorable for better simulating the electromagnetic interference environment based on the amplitude modulation and frequency modulation communication systems, realizes the simulation of the electromagnetic interference environment by adopting a small amount of equipment instruments, has simple test scheme and simple and convenient operation, and effectively reduces the calculation complexity of the test, thereby reducing the hardware requirement of the test equipment. Meanwhile, the electromagnetic interference test system of the radio system is arranged in a semi-anechoic chamber, and other electromagnetic interference in the space can be effectively eliminated, so that the test difficulty can be effectively reduced, the contact degree of the simulation test is improved, and the accuracy of the test result is improved.
Example two
Referring to fig. 2, a flowchart of a method for testing electromagnetic interference of a radio system according to a second embodiment of the present invention is shown, where the method includes steps S201 to S202.
S201, receiving a first signal transmitted by an amplitude modulation transmitter and a third signal generated by a second signal transmitted by the frequency modulation transmitter through a receiving antenna in a preset receiving frequency band; the first signal is transmitted by the amplitude modulation transmitter through a first transmitting antenna according to a preset first working frequency point, and the second signal is transmitted by the amplitude modulation transmitter through a second transmitting antenna according to a preset second working frequency point.
In the above embodiment, it is preferable that before step S201, the method further includes:
determining a main working frequency point, transmitting power and a communication distance of an amplitude modulation transmitter, and setting a first working frequency point of the amplitude modulation transmitter;
the method comprises the steps of determining a main working frequency point, transmitting power and a communication distance of a frequency modulation transmitter, and setting a second working frequency point of the frequency modulation transmitter.
Further, preferably, a receiving frequency band of the receiver is preset;
and selecting a corresponding receiving antenna according to the receiving frequency band of the receiver.
Illustratively, the receiver can be a receiver with frequency modulation reception, and when the receiving frequency band of the receiver is 30 MHz-200 MHz, a biconical antenna is selected; and when the receiving frequency band of the receiver is 200 MHz-1 GHz, selecting the horn antenna.
It should be noted that, in this embodiment, the first operating frequency point and the second operating frequency point are different. Exemplarily, in the working frequency band of the am transmitter, the first working frequency points fA1, fA2, fA3 are respectively selected, and in the working frequency band of the am transmitter, the second working frequency points fB1, fB2, fB3, fB4 are respectively selected, and the above test is repeated; wherein, the selected working frequency point needs to satisfy the conditions: fA1 ≠ fA2 ≠ fA3 ≠ fB1 ≠ fB2 ≠ fB3 ≠ fB 4. Therefore, when the AM transmitter and the FM transmitter work at different working frequency points, the receiver records the signal intensity and the frequency point of the third signal received by the receiving antenna in the receiving frequency band.
S202, analyzing the frequency point and the signal intensity corresponding to the third signal, and determining the frequency point and the interference value of the electromagnetic interference generated by the radio system.
It should be noted that, by analyzing the frequency point and the signal strength of the received third signal, it is determined whether the electromagnetic interference phenomenon exists in the radio communication system environment, and then the frequency point and the interference value of the generated electromagnetic interference are determined, and the theoretical reason of the generated electromagnetic interference can be researched.
The electromagnetic interference testing method for the radio system provided by the embodiment of the invention transmits a first signal to a receiver through a first transmitting antenna according to a preset first working frequency point by an amplitude modulation transmitter, transmits a second signal to the receiver through a second transmitting antenna according to a preset second working frequency point by a frequency modulation transmitter, further receives a third signal generated by the first signal and the second signal through a receiving antenna in a preset receiving frequency band by the receiver, and determines a frequency point and an interference value of electromagnetic interference generated by a radio system by analyzing a frequency point and signal intensity corresponding to the third signal, so that the electromagnetic interference existing in the radio communication system can be determined by analyzing the electromagnetic environment between the amplitude modulation transmitter and the frequency modulation transmitter, and the electromagnetic interference environment based on the electromagnetic interference between the amplitude modulation communication system and the frequency modulation communication system can be better simulated, the simulation of the electromagnetic interference environment is realized by adopting a small amount of equipment instruments, the test scheme is simple, the operation is simple and convenient, and the calculation complexity of the test is effectively reduced, so that the hardware requirement of the test equipment is reduced. Meanwhile, the electromagnetic interference test system of the radio system is arranged in a semi-anechoic chamber, and other electromagnetic interference in the space can be effectively eliminated, so that the test difficulty can be effectively reduced, the contact degree of the simulation test is improved, and the accuracy of the test result is improved.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.
Claims (8)
1. A radio system electromagnetic interference test system, installed in a semi-anechoic chamber, comprising: the system comprises an amplitude modulation transmitter, a frequency modulation transmitter, a receiver, a first transmitting antenna, a second transmitting antenna and a receiving antenna;
the first transmitting antenna is connected with the amplitude modulation transmitter, the second transmitting antenna is connected with the frequency modulation transmitter, and the receiving antenna is connected with the receiver;
the amplitude modulation transmitter is in communication connection with the receiver through the first transmitting antenna and the receiving antenna, and the frequency modulation transmitter is in communication connection with the receiver through the second transmitting antenna and the receiving antenna;
the receiving antenna is arranged at a position where the vertical distance between the amplitude modulation transmitter and the frequency modulation transmitter is a second preset distance.
2. The radio system emi testing method as claimed in claim 1, wherein said first predetermined distance is 0.2m to 0.5 m.
3. The radio system emi testing method as claimed in claim 1, wherein said second predetermined distance is 1 m.
4. A method for testing electromagnetic interference in a radio system as claimed in claim 1, characterized in that said receiver is a radio with fm reception.
5. A radio system electromagnetic interference test method, adapted to the radio system electromagnetic interference test system according to any one of claims 1 to 4, said method comprising the steps of:
receiving a first signal transmitted by an amplitude modulation transmitter and a third signal generated by a second signal transmitted by the frequency modulation transmitter through a receiving antenna in a preset receiving frequency band; the first signal is transmitted by the amplitude modulation transmitter through a first transmitting antenna according to a preset first working frequency point, and the second signal is transmitted by the amplitude modulation transmitter through a second transmitting antenna according to a preset second working frequency point;
and analyzing the frequency point and the signal intensity corresponding to the third signal, and determining the frequency point and the interference value of the electromagnetic interference generated by the radio system.
6. The method of claim 5, wherein the first operating frequency point and the second operating frequency point are different.
7. The method of claim 5, wherein prior to receiving the first signal transmitted by the AM transmitter and the second signal transmitted by the FM transmitter via the receiving antenna within the predetermined receiving frequency band, further comprising:
determining a main working frequency point, transmitting power and a communication distance of an amplitude modulation transmitter, and setting a first working frequency point of the amplitude modulation transmitter;
the method comprises the steps of determining a main working frequency point, transmitting power and a communication distance of a frequency modulation transmitter, and setting a second working frequency point of the frequency modulation transmitter.
8. The method of claim 5, wherein prior to receiving the first signal transmitted by the AM transmitter and the second signal transmitted by the FM transmitter via the receiving antenna within the predetermined receiving frequency band, further comprising:
presetting a receiving frequency band of a receiver;
and selecting a corresponding receiving antenna according to the receiving frequency band of the receiver.
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| CN111654341A (en) * | 2020-05-29 | 2020-09-11 | 北京小米移动软件有限公司 | Method, device, equipment and storage medium for testing wireless communication equipment |
| CN112162159A (en) * | 2020-09-08 | 2021-01-01 | 中电科仪器仪表有限公司 | Electromagnetic interference field test method based on signal identification |
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| CN112162159A (en) * | 2020-09-08 | 2021-01-01 | 中电科仪器仪表有限公司 | Electromagnetic interference field test method based on signal identification |
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Address after: 610041 1-6, building 3, No.9, Wuke East Third Road, Wuhou New Town Management Committee, Wuhou District, Chengdu, Sichuan Province Patentee after: GRG METROLOGY & TEST (CHENGDU) CO.,LTD. Patentee after: Radio and TV Measurement and Testing Group Co.,Ltd. Address before: 610041 1-6, building 3, No.9, Wuke East Third Road, Wuhou New Town Management Committee, Wuhou District, Chengdu, Sichuan Province Patentee before: GRG METROLOGY & TEST (CHENGDU) CO.,LTD. Patentee before: GUANGZHOU GRG METROLOGY & TEST Co.,Ltd. |