What are the RF Test Cables shielding attenuation test methods?

In order to improve the anti-interference ability of the RF Test Cables and reduce the pollution to the surrounding electromagnetic environment, it is a simple and effective method to use shielded cables. The shielded cable can not only prevent the leakage of the signal inside the cable, but also prevent the external interference signal from entering the inside of the cable. The shielding performance of a shielded cable is generally measured by the shielding attenuation of the cable, which is an important indicator to characterize the electromagnetic compatibility (anti-interference and anti-leakage) of the coaxial cable, which is defined as: as = 10 lg ( Pin / Pmax ) 

                                         
where Pin is the injected power and Pmax is the maximum power of radiation. Due to the variety of shielding layers of RF Test Cable, different shielding materials and shielding structures, the shielding attenuation of RF Test Cable will be very different. In order to provide an accurate reference for engineering evaluation, comparison, design and use of shielded cables, the shielding attenuation of RF Test Cable must be measured. Therefore, the testing technology of cable shielding attenuation is becoming the concern of many researchers.

Coaxial cable Assemblies is a general term for coaxial cables used to transmit radio frequency signals or energy. Its working frequency is usually 15 kHz ~ 20 GHz, mainly used in communication broadcasting, television, microwave relay, radar, navigation and telemetry and other fields. The test methods of RF Test Cable shielding attenuation can be divided into: a. Indirectly describe the RF coaxial cable surface transfer impedance by measuring it, the triaxial method is a typical transfer impedance measurement method; b. Directly measure the shielding of RF Test Cable Attenuation, the more commonly used power absorption clamp method, reverberation chamber method, GTEM cell method and so on. Among the above test methods, the reverberation chamber method and the GTEM cell method are based on the field point of view, and the rest of the test methods are based on the circuit point of view.