Which two metrics are commonly used to assess receiver performance?

• A. Sensitivity (min detectable signal) and selectivity (ability to reject adjacent channels)
• B. Bandwidth and gain
• C. Power consumption and temperature stability
• D. Noise figure and intermodulation performance

Answer: (A)

Two metrics commonly used to assess receiver performance are sensitivity and selectivity.

Sensitivity is about how weak a signal the receiver can detect and still produce a usable output. It’s the minimum input signal level, often given as a dBm value at a specified output SNR or BER. This tells you how faint a transmission can be and still be decoded reliably.

Selectivity measures the receiver’s ability to reject signals on nearby frequencies. It describes how well the receiver isolates the desired channel from adjacent channels and interferers, typically expressed as adjacent-channel rejection or similar specs in dB. Good selectivity keeps strong nearby signals from masking the wanted signal.

Understanding both together highlights a key balance: you want enough sensitivity to pull in weak transmissions, and enough selectivity to keep neighboring signals from causing interference. Other metrics like bandwidth, gain, power consumption, or temperature stability are important in design and operation, but sensitivity and selectivity are the core pair that define how well a receiver actually performs in a crowded spectrum.