Home/Support / Knowledge Base / Receiver sensitivity and interference blocking specifications

Receiver sensitivity and interference blocking specifications

It is a common misconception that receiver sensitivity can be a bad thing. Some will say that a more sensitive receiver is more susceptible to interference. If that were the case then it would logically follow that the less sensitive the receiver, the better the radio performs in the presence of interference. This statement is simply not true, because a less sensitive receiver has less performance in both the presence and absence of interference.

The truth is that a receivers ability to overcome interference is not related to the receiver sensitivity but is measured by a separate specification - the receiver blocking specification. The blocking specification is a measure of the relative strength of interfering signals to the carrier (desired) signal that causes the receiver sensitivity to degrade by 3dB.

Example:

With the MaxStream 9XStream radio modem, an interfering signal 1MHz away from the carrier frequency must be 60 dB stronger than the desired signal to cause the receiver sensitivity to degrade by 3dB.

If the desired signal is arriving at the radio modem antenna port at a level of -107dBm (3 dB above sensitivity level of -110dBm for 9600 baud modem); the reception will be sucessful as long as the interference arriving at the antenna port from undesired sources is not stronger than -47dBm (-107+60).

The following whitepaper contains further explanation and examples.

Relevant Files

Last updated: Aug 08, 2017

Recently Viewed Articles

No recently viewed articles
Contact a Digi expert and get started today! Contact Us