desense
desense
(OP)
Dose everyone know desense of wireless problem?
what is the meaning of desense/
what is the meaning of desense/
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RE: desense
At each subsequent RF or Intermediate Frequency (IF) stage, the bandwidth typically becomes narrower and narrower. The AGC loop must control the RF and IF gain closer to the front end (and thus the AGC circuit is exposed to a wider bandwidths than the entire receiver end-to-end). Thus, an off-channel signal can affect the AGC, but you don't hear the off-channel signal because it isn't within the bandwidth of the whole chain. But the off-channel signal does cause the receiver to go deaf due to the action of the AGC.
Another possible mechanism is saturation, but the AGC mechanism is more likely since it can occur at more reasonable amplitudes. Except with digital radios (those with DSP in the signal path) - they need lots of bits (bit depth) to accomodate weak signals accomanied by off-channel stronger signals - otherwise 'digital saturation'. 16 bits is usually inadequate for such application.