What Does Image Rejection Mean in Relation to a Microphone System?

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Question: Answer:

Question:

What does image rejection mean in relation to a microphone system?

Answer:

Image rejection is a technical specification that refers to a wireless microphone receiver's ability to filter out unwanted radio signals that can interfere with the audio transmission. These unwanted signals occur at what's called the image frequency, a by product of how receivers convert radio signals to intermediate frequencies (IF) for processing.
Wireless microphone systems often use superheterodyne receivers, which mix the incoming signal with a local oscillator to produce an IF. Unfortunately, this process can also allow a second, unwanted signal (the image frequency) to produce the same IF, potentially causing interference.
A receiver with high image rejection (typically measured in decibels) is better at ignoring these unwanted signals, resulting a cleaner audio, no or fewer dropouts, improved signal reliability, especially in environments with heavy RF traffic.