Does the greater the power of the signal jammer, the greater the shielding range?

Discussion on the uncertainty of equipment power and shielding distance (range, area)

Several parameter issues that are helpful to the shielding effect:
1) Output power
①The output power of the shield
②The performance of antenna radiation (antenna gain, directivity, etc.)
③Other
2) How the shielding works
Nowadays, mobile phones are all digital signals, and the anti-interference ability of digital signals is very strong. Generally, the effect of using analog signal technology to interfere with digital signals is poor. Therefore, digital signals must be used to interfere with digital signals. The interference effect is quite different. The jammer using digital jamming signal technology has lower power and higher efficiency than the jammer using analog signal jamming technology.
3) Indoor and outdoor are different
The synthesis, attenuation, reflection and other analysis of indoor mobile phone signals and interference signals are very complicated.
4) Before being shielded, the strength and quality of the local cell phone signal has a great impact on the shielding. Different mobile phones have different effects. Generally, mobile phones with strong ability to receive weak signals may not have good anti-interference effects.
5) The direction of the base station and the direction of the shielded area of ​​the mobile phone also affect the shielding effect.
6) Shielding distance and the characteristics of radio signal transmission distance. Now, the shielding distance is simply discussed in terms of the attenuation of radio signal transmission in free space. According to the transmission theory formula, the signal strength is attenuated by 6db every time the radio wave transmission distance is doubled (the signal power is reduced by 4 times) ). Then we take a mobile phone jammer GSM 900MHZ as an example. If the signal strength of a mobile phone in an area that needs to be shielded is -50dbm, and the effective shielding distance of the jammer is 10 meters, the change of the signal strength of the mobile phone will directly affect the shielding distance.
①Generally, the signal strength in space is about -60 to -70dbm, and the highest within a few hundred meters of the base station can reach about -40dbm, and the mobile phone reception strength range is generally between -35 to -95dbm.
②The higher the signal power of the space mobile phone, the shorter the shielding distance.

The above discussion is based on the conclusion drawn based on the law of radio signal transmission in free space (so-called free space is similar to space). In reality, there are many obstacles on the ground that affect the transmission of radio waves. The above conclusions can only be qualitatively used as a reference, especially The above rules are very different from the actual indoors. Therefore, it is difficult to calculate this problem accurately at the moment, and can only be determined based on the actual situation on site. Accurate construction projects must carry out preliminary research and signal testing, and then design specific solutions, and then require timely follow-up testing and make certain corresponding supplements to be foolproof, that is, to achieve the effect of strict shielding. For example, when interfering with someone’s language, how much sound can be used to interfere with the volume between him and the audience, speech intelligibility, room echo, and the distance between the speaker and the audience and the interfering person are also related to factors.