The use of the shielding box is very extensive. It can shield the electromagnetic radiation and also prevent the electromagnetic from entering a certain area, so as to shield the interference signal. There are various types of shielding boxes, each with its own advantages.
According to the application field, the shielding box can be divided into the following types:
1. Electromagnetic shielding box: mainly used in electromagnetic wave testing and electromagnetic compatibility testing, which can effectively shield the influence of external electromagnetic signals, ensure test accuracy, have a wide frequency range and good Shielding effect.
2. Shortwave shielding box: mainly used for shielding between shortwave reception and shortwave transmission to achieve interference-free communication, with good anti-interference performance and signal transmission quality.
3. Microwave shielding box: Mainly used in microwave testing and microwave communication fields, it can shield microwave signals with high frequency range and short wavelength, and has excellent high-frequency shielding performance and stability.
4. Radiation shielding box: mainly used for radio radiation testing and adjustment, with good anti-interference performance and stability.
According to the structure, the shielding box can be divided into the following types:
1. Fully enclosed shielding box: the equipment shell is made of a fully sealed structure, and protective measures such as grounding are added to prevent the magnetic field from contaminating the interior and avoiding the noise in the external environment from affecting the normal operation of the equipment. , To prevent dust and sundries from entering the interior to cause short circuit, the fully enclosed shielding box is currently the most used shielding box.
2. Semi-enclosed shielding box: that is, a layer of shell is put on the outside of the box to prevent external noise from invading the internal electronic circuit. This kind of shielding box has poor heat dissipation performance and is prone to overheating damage.
3. Open shielding box: Put a layer of net cover on the outside of the box to reduce external interference and low cost, but it is easily affected by external dust and sundries and shortens the service life.
The working principle of the shielding box is to use the internal shielding material to reflect, absorb, and scatter electromagnetic wave signals, and control the path of signal transmission, so as to prevent signal leakage or external interference. The outside of the shielding box is mostly metal material, which can be used as a part of the shielding layer.
The application fields of the shielding box mainly include coupling test, RF function test, EMI test, EMS test, wireless communication test, sensitivity test, Bluetooth, mobile phone and other equipment testing, suitable for the need to protect electromechanical devices from interference, guarantee testing, debugging, communication, etc. Where security is applied. For example:
1. Electromagnetic compatibility (EMC) testing needs to be carried out in a controlled environment, free from electromagnetic field interference, and without causing unnecessary interference to the electromagnetic environment, to ensure the accuracy of the test.
2. Radio testing and communication are faster and more convenient. It is necessary to ensure the accuracy and confidentiality of information transmission. To ensure that information is not leaked, it is necessary to strengthen the physical isolation of the network.
3. High-precision testing or measurement needs to prevent the interference of external electromagnetic noise on the equipment. Electromagnetic interference will cause abnormal operation of the equipment, which is related to the accuracy of the detection data.
4. Where sensitive information is handled or where information security needs to be ensured, appropriate shielding materials and shielding measures are required.
It should be noted that different types of shielding boxes are suitable for different applications and equipment with different power, frequency range, field strength, waveform, sensitivity, etc. Before use, it needs to be carefully checked and tested to judge the shielding effect to ensure the application effect and safety.