How many types of electric wave anechoic test chamber laboratories are there? How many types of radioactive anechoic test chamber laboratories do you know?
Classified by the use of the radio wave anechoic test chamber
Electric wave anechoic test chamber can be divided into antenna diagram test microwave anechoic chamber, radar cross-section anechoic test chamber, electromagnetic compatibility (EMC) anechoic test chamber, electronic warfare (countermeasures) anechoic test chamber according to the purpose.
The antenna is an indispensable part of EMC testing, and the accuracy of antenna parameters will have an impact on the test results. Microwave Anechoic Chamber Antenna diagram test chamber is the laboratory specializing in testing antenna parameters, such as antenna directional diagram and gain, etc.
Radar cross-section anechoic test chamber
Used to test the radar cross-section contained in ships, aircraft, missiles (rockets), vehicles, etc.
An electromagnetic compatibility anechoic test chamber
This is a more widely used electric wave chamber, for general electronic products, in its official use in the market before the radiation emission and radiation immunity test, in order to determine whether the product can be put on the market, an electromagnetic compatibility test chamber can complete the test task.
An electromagnetic compatibility test chamber
This is a more widely used electric wave chamber, for general electronic products, in its official use in the market before the radiation emission and radiation immunity test, in order to determine whether the product can be put on the market, an electromagnetic compatibility test chamber can complete the test task.
Electronic warfare (countermeasures) anechoic test chamber
Simulate the working condition of the equipment system under the situation of electromagnetic interference in real combat.
Classification by the shape of the radio wave anechoic test chamber
Electric wave anechoic chambers can be divided into rectangular electric wave anechoic test chambers and cone-shaped electric wave anechoic test chambers according to the shape.
Rectangular anechoic chamber
At present, most of the radio wave chambers are built into rectangles, and the standard 3m method, 5m method, and 10m method chambers are all rectangle anechoic chambers.
Cone-shaped anechoic chamber
This type of chamber can effectively avoid side, top, and ground reflections, which often affect the performance of rectangular anechoic chambers. The rectangular radio wave anechoic chamber has poor performance at low frequencies (below 1GHz), and the conical radio wave anechoic chamber does not have this disadvantage. So it is often used to test or measure satellite communications as well as entire satellites.
Classification according to the paste method of absorbing material on the inner surface
According to the way of pasting the absorbing material on the inner surface, the chamber can be divided into the half-wave chamber, full-wave chamber, and improved half-wave anechoic test chamber.
Semi-wave anechoic test chamber
A Semi-wave anechoic chamber is a shielded chamber with wave-absorbing materials on all five sides except for the ground (grounded plate). As an alternative to the outdoor open test site, the semi-wave chamber has been recognized by domestic and international standards and has become a widely used EMC test site.
However, the semi-wave anechoic chamber has its own defects, such as the lift of the antenna and the instability of the measurement value caused by the reflection of electromagnetic waves from the ground plane. The semi-wave anechoic chamber is used for EMC radiation emission and electromagnetic radiation sensitivity measurement. The main performance indicators are measured by normalized field attenuation (NSA) and test surface field uniformity (FU).
Full-wave anechoic test chamber
A full-wave anechoic chamber is a shielded chamber with all inner surfaces equipped with wave-absorbing materials. It is used to simulate the propagation environment of free space. The full-wave anechoic chamber completely abandons the principle of planar earth interference and solves many of the defects inherent in the half-wave anechoic chamber.
At the same time, because of the simulation of free space, no reflection occurs, there is no interference model, the consistency of horizontal polarization, vertical polarization is better; and there are no 3m and 10m of the fight, sometimes only 3m can, for electromagnetic compatibility test provides a low cost, low cost, convenient and efficient, flexible and accurate test method.
The full-electric wave chamber is mainly used for microwave antenna system parameter measurement. Usually with the static area, reflectivity level, cross-polarization degree, multi-path loss, amplitude uniformity, and operating frequency, and other six indicators to express.
Improved half-wave anechoic test chamber
The improved semi-wave anechoic chamber is a semi-wave chamber equipped with additional absorbing material on the grounded flat plate. As the radio wave anechoic chamber is not only the test site of the harassment radiation but also the immunity test site.
Equipment immunity (equipment sensitivity) test to assess the immunity of the EUT to radiation from space electromagnetic field performance, the test should be conducted in the wave chamber, the ground should be laid on the absorbing material.
Therefore, for the semi-wave anechoic chamber, the test must be made up of absorbing material so that there is no reflection, which becomes a modified semi-wave chamber. In the test, radiation emission is when the absorbing material is removed and reverted to a semi-wave anechoic chamber.
According to the size of the anechoic test chamber classification
The size of the electric wave anechoic test chamber can be divided into the ultra-tight predictive full-wave anechoic chamber, small practical size electric wave anechoic chamber, small electric wave anechoic chamber, 3m electric wave anechoic chamber, 5m electric wave anechoic chamber, 10m electric wave anechoic chamber.
Ultra-tight predictive full-wave anechoic test chamber
The size is about 4.6m×2.5m×2.75m. It is mainly used for immunity testing, but also for predictive testing of radiation emission. This chamber occupies little space, low cost, especially because it is assembled, so it can be disassembled and installed anywhere. And it is easy to upgrade to the 733 type chamber and the standard 3-meter method chamber. This kind of chamber is very suitable for small and medium-sized enterprises.
Small practical size electric wave anechoic test chamber
The size is about 7m×3m×3m, mainly used for RF immunity, emission prediction, and free space emission test. The suitable frequency is 26MHz~1GHz, the cost is low, and it is suitable for small and medium-sized enterprises to do internal testing.
Small radio wave anechoic test chamber
The size is about 8m×4m×4m, mainly used for RF immunity emission prediction and free space emission test. Suitable for frequency 26MHz～1GHz, slightly higher and larger than small practical size radio wave anechoic chamber.
3m radio wave anechoic test chamber
The size is about 9m×6m×6m. It is used for RF immunity and emission test size below 2m. Is commonly used internationally instead of the open field of the experimental site.
5m radio wave anechoic test chamber
The size is about 11m×7m×9m. The price is more expensive than the 3m radio wave anechoic chamber, but it is only one-third of the price of the 10m anechoic chamber. The performance is superior to the 3m anechoic chamber in a wide range, and the conversion correction relationship with the 10m anechoic chamber is superior to the conversion correction relationship of the 3m anechoic chamber to the 10m anechoic chamber. This chamber has been gradually promoted and applied.
10m radio wave anechoic test chamber
The size is about 21m×12m×9m. The cost is expensive. Test performance effect is more accurate than the previous small wave anenchoic test chamber data and often used in large equipment electromagnetic compatibility radiation site testing, currently reused for large units.
These are the anechoic test chamber types we talked about today. Do you know any other anechoic test chambers? If so, please leave your comments.
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