How should the filter bandwidth of a receiver's IF section be relative to the bandwidth of a received signal?

The filter bandwidth of a receiver's intermediate frequency (IF) section should be slightly greater than the bandwidth of the received signal to effectively capture the desired signal while minimizing the impact of noise and unwanted signals. This approach allows the receiver to accommodate variations in the signal due to factors such as frequency shifts or signal distortion, which can occur during transmission.

When the filter bandwidth is slightly greater than the signal bandwidth, it ensures that the complete signal is captured without clipping or losing critical parts. Additionally, having a slightly wider bandwidth helps to enhance the receiver's sensitivity and reduce the potential for signal distortion while still allowing for effective filtering of noise and adjacent channel interference.

A bandwidth that is much greater than the received-signal bandwidth may result in increased noise and reduced overall system performance, as it allows more unwanted signals to be included in the output. An equal filter bandwidth may be insufficient to cover variations in the signal, potentially leading to the loss of important signal components. Conversely, a filter bandwidth that is slightly less than the received-signal bandwidth could result in missed signal information, as parts of the signal would be outside the filter's range, which can degrade reception quality.