A spectrum analyser with a noise figure of has its resolution bandwidth set to and…
PHYSICS · Multi-part · Fermi University Physics · Electronics, Instrumentation & Communication · Sensors, detectors and experimental instrumentation · Communication systems and RF engineering
Inside the Instrument, Ch Transmission lines, grounding and the bench
Problem
A spectrum analyser with a noise figure of 12dB has its resolution bandwidth set to 3kHz and its detector in log-averaging mode. An ordinary marker on its noise floor reads −110dBm; the instrument has applied no bandwidth normalisation and no detector correction. Take the noise bandwidth equal to the resolution bandwidth.
((a)) Find the noise density at the input, in dBmHz−1.
((b)) Find the analyser's own floor density, and decide whether the measured density belongs to the source.