Characteristics and Signal Interference Factors of Wireless Intercom System
The wireless intercom system is simple and convenient to operate, and can be used as a high-altitude operation and remote command. It is flexible to use, and can break the influence of buildings and obstacles. It can achieve little interference, no obstacles, and a large degree of use, but there are also some factors. , it will cause interference to the wireless counter-sword system, such as radio waves, or industrial electrical equipment, and electromagnetics, etc., which are described in detail below.
1. Features of wireless intercom system
1. Simple and fast operation, high flexibility
It is understood that the wireless intercom system has the characteristics of simple and flexible operation and fast voice transmission. The system can realize multi-party communication, flexible and convenient without pressing any buttons. You can answer when you are speaking, and you can also speak when you are answering, without the need for a host or repeater. It can be operated with only simple settings. The wireless dialogue system is suitable for aerial work, radio command, remote communication and other operations.
2. Wide coverage
The wireless intercom system adopts the conventional wireless communication system, and responds to all calls in the way of talking. The system continuously covers the communication between buildings without blind spots, thereby breaking the obstacles caused by the building structure and environment to wireless signals. So that the signal can penetrate smoothly from the ground floor to the underground floor, which improves the coverage of the wireless intercom system in a real sense.
3. High call quality
A high-quality wireless intercom system must not only ensure high call quality, but also avoid antenna radiation sources that interfere with other systems inside the building. It is carried out in strict accordance with the standard that the electromagnetic wave interference field strength within a certain range is not greater than 3V/m.
Second, the common interference factors of wireless intercom system
1. Radio disturbance
from various wireless transmitters. It is characterized by a wide frequency range, covering almost all frequency bands used. But the frequency for a specific station is generally fixed, so it can be protected. In addition, because the radio frequency management is relatively complete, such interference can be limited to a small limit.
2. Industrial interference
From various electrical equipment, such as motors, power lines, power switches, electric ignition (such as car ignition) devices, etc. Such interference is generally in the lower frequency range, such as car ignition interference in the tens of megahertz range. With shielding and sophisticated filtering measures, industrial interference can be avoided to a large extent.
3. Electrical interference
From thunder and lightning, magnetic storms, sunspots and cosmic rays, etc., they are closely related to seasonal and climate changes. Different regions are also very different, such as near the equator and the two regions. In the year when the sunspot changes (about 11 years a cycle), the interference of the sky and electricity increases, and sometimes short-wave communication is interrupted for a long time. signal jammer
4. External interference
From various electronic device resistors, antennas, and transmission lines inside the channel. The random thermal motion of molecules or electrons in these electronic devices, forming so-called ripple noise, creates additive interference to communication signals. Mainly this noise is called thermal noise. From the mechanism, it is a Gaussian statistical feature and is an important factor of communication system interference.