HF Receiver Testing: Issues Advances

摘要

1. Sensitivity 1.1 Test signal level for a given signaloise ratio in a given bandwidth 1.2 Usually stated as Minimum Discernible Signal (MDS) or noise floor: 1.2.1 Input in dBm at 500 Hz bandwidth to raise audio output level by 3 dB 2. Selectivity & shape factor 2.1 IF or detection bandwidth at -6 and -60 dB points on passband curve 3. Reciprocal mixing dynamic range (RMDR) 3.1 Test signal level at a given offset from RX freq. to raise audio output by 3 dB, minus MDS 3.1.1 A function of local-oscillator phase noise 4. 2-signal, 3rd-order IMD dynamic range (DR3) 4.1 Input power of each of two equal test signals at a given spacing and 500 Hz bandwidth to raise demodulated IMD product by 3 dB, minus MDS 5. Blocking gain compression 5.1 Level of strong signal at a given offset from weak signal to reduce level of demodulated weak signal by 1 dB. RX tuned to weak signal; 500 Hz bandwidth.