Each wireless transmitting device occupies a frequency bandwidth when it is working, just like each car occupies a lane. Here, the frequency is like a highway, and the bandwidth is like that there are countless lanes on the road. The microphone receiver is like a waiter on this driveway. When the wireless device is working, if other devices use your frequency band. on
This has nothing to do with whether you use genuine or replica, big factory or small factory wireless microphone. All microphone manufacturers in the world have no way to completely solve the problem that this microphone receiver is interfered by other co-frequency signals. Of course, excellent manufacturers will use technology to minimize this possibility. The transmitter minimizes spurious emissions such as: parasitic, intermodulation, harmonics, etc., while the receiver uses SQ (Squelch, squelch threshold) or narrow. Frequency work, frequency hopping technology, etc. This is used to resolve the effects of interference on its system and to increase the number of wireless microphones in the system.
However, the current relatively effective solution is to use frequency hopping technology. This technology for military communication was first developed as a kind of spread spectrum technology for confidential communication after World War II. It has been widely used in civil communications, such as CDMA communications.