I believe everyone is not unfamiliar with cell phone jammer. In recent years, various jammers on the market have emerged one after another. Everyone claims that their jammers are particularly good, and the materials are full of moisture, making you confused. Good or bad, then what should we know about the jammer?
The first point is that the greater the power of the mobile phone signal shielding device, the farther the shielding effect is. In fact, this is not completely correct. Many manufacturers use ordinary users to detect the actual power status, deliberately exaggerating the openness of shielding power. Cause the equipment’s nominal power index to lose its reference value. Regarding large-scale shielding systems, shielding skills are the decisive factor that affects shielding effectiveness. The advantages of advanced shielding skills are far greater than the output power factor of shielding equipment. The second point is to use directional antennas to avoid external disturbances. This is also incorrect, because the directional antenna covers the main lobe, side lobes and back lobes. The main lobe masking angle is defined as the cell phone signal masking inclusion angle when the external power of the main lobe drops by 3dB. In other words, the radiation intensity on the side and back of the directional antenna is only much lower than the main lobe. Therefore, if the space close to the antenna is still relatively shielded, the reflection of the shielded building will still cause external disturbance. In addition, if it is used improperly, it will cause upstream disturbance, and the scale of disturbance will be even greater. Therefore, whether the equipment skills are satisfactory, the use of antennas, and the debugging of the system are far more meaningful than whether to use directional antennas. The third point is that we all think that the cell phone signal shielding interval is a hard indicator. In fact, the interval is not an absolute value. It is related to the strength and quality of the spatial signal. Simply put, the interval is meaningless. For the same shielding power, if the interval is 100 meters-70 decibels at the weak point, then only 12.5 meters at the strong-52 decibels. The shielding interval is related to the antenna gain. The same power shielding host uses different gain antennas, and the interval will be very different. For example, the antenna interval with a gain of 16 db is 100 meters, and the antenna interval with a gain of 4 db is only 25 meters. To sum up, when selecting a mobile phone signal, it is necessary to combine the actual situation of the scene environment, not only trust the hearing, but also personally test it.
