What follows is the summarization of cell phone jammer

In order to obtain good electromagnetic shielding, should be: ① use of a good conductor; ② to shield a certain thickness, in order to suppress the magnetic field, generally greater than 10 times the thickness of the penetration depth; ③ avoid openings, cracks caused by shielding effect is reduced, the maximum size of apertures should generally be less than the maximum frequency of the electromagnetic wavelength of 1 / 20. 4 In order to measure the shielding effectiveness of the shielding effect of the shield is the shielding effectiveness of shielding is not added when the field strength of a point (E0, H0) and with a little added masked field strength (Es, Hs) ratio and in decibels (dB ) that E 0 (no shield) SE E = 20 lg of the electric field E s (shielded) H 0 (no shield) SE H = 20 lg of the magnetic field H s (shielded) shielding effectiveness SE greater shielding effect that the more good. SE = R + A + BR for the return loss,What follows is the summarization of cell phone jammer . A is the absorption loss, B is a complete multi-reflection loss 3.2.1 shielding effectiveness of shielding integrity of the shield is a completely closed shielding structure, the electromagnetic field only through the shield wall to access the closed structure. 1. Reflection loss of electromagnetic wave propagation of electromagnetic waves to the interface of different media electromagnetic wave reflection and transmission occurs through the shield of reflection and transmission when the general Zl>> Z2 | Z1 | return loss R = 20 lg 4 | Z2 | 2. What follows is the application and features of    cell phone jammer .Loss of electromagnetic wave absorption of electromagnetic waves reach the body shield when the magnetic field strength come through H = H 0 e? T / δ E = E 0 e? T / δ t shield the electric field strength of the absorption loss A = 20 lg e = 8.69 δ t δ 3. Multiple reflection loss of electromagnetic wave electromagnetic wave shielding body piercing, in the place come through reflection, the reflected wave back into the surface is reflected again, and so forth, until its energy is absorbed to a negligible so far.
Principles defined in electromagnetic shielding using magnetic shielding or low resistance metal material (aluminum, copper) made from the container will need to isolate the equipment, devices, circuits all wrap called the shield. Shielding effects: one is the container equipment, devices, circuits do not interfere with the receiver outside the container, and the second is a container outside sources of electromagnetic interference on the receiver inside the container does not constitute interference shielding categories: shielded electrostatic shielding: mainly electrostatic coupling to prevent interference; magnetic Shield. What follows is the main functions of    cell phone jammer     .The main low-frequency magnetic field to prevent interference; electromagnetic shielding: mainly high-frequency field to prevent interference. 1. electrostatic shielding to eliminate the two devices, devices and circuits as distributed capacitance coupling between the electrostatic field generated by electrostatic shielding interference call.
Reflection attenuation due to air and the characteristic impedance of the shield are not equal, wave reflection, resulting in the incident electromagnetic energy through the weakening of the interface. 2. Absorbed into the decay part of the electromagnetic wave shielding, the induced eddy current, weakened the field, and eddy current losses, resulting in attenuation of electromagnetic energy.What follows is the installation steps and methods of    cell phone jammer     .