| Measurement of analog modulation signals |
| Center frequency |
|
10 MHz to 3 GHz |
| Demodulation bandwidth |
|
2 MHz, 1 MHz, 500 kHz, 300 kHz, 200 kHz, 100 kHz, 50 kHz, 30 kHz, 20 kHz, 10 kHz (nom.) |
| Bandwidth accuracy |
|
< ± 5% (nom.) |
| Display |
AM |
carrier power, carrier frequency offset, AM modulation depth, modulation frequency, THD, SINAD |
| FM |
carrier power, carrier frequency offset, FM deviation, modulation frequency, THD, SINAD |
| Carrier power |
| Carrier power measurement accuracy |
|
add 0.2 dB, see section Level measurement uncertainty |
| Display resolution |
|
0.1 dB |
| AF (modulation frequency) 1 |
| Range |
AM |
20 Hz to 100 kHz (nom.) |
| FM |
20 Hz to 200 kHz (nom.) |
| Resolution |
|
1 Hz |
| Measurement uncertainty |
1 kHz ≤ AF ≤ 200 kHz |
±(1 % of measured value) (nom.) |
| 20 Hz ≤ AF < 1 kHz |
± 1 Hz (nom.) |
| AF filters |
| Lowpass |
audio decimation |
bypass, 1/10, 1/30, 1/100 (nom.) |
| Deemphasis |
FM demodulation and demodulation bandwidth 200 kHz and 300 kHz |
off, 50 μs, 75 μs (nom.) |
| AM demodulation 2 |
| Measurement range |
modulation depth |
5 % to 95 % (nom.) |
| Modulation depth uncertainty |
|
±(4 %) (nom.) |
| FM demodulation 3 |
| Measurement range |
frequency deviation |
10 kHz to 400 kHz (nom.), max. 0.4 × demodulation bandwidth |
| Deviation uncertainty |
|
±(0.04 × (AF + deviation)) (nom.) |
| Modulation distortion 1, 2, 3 |
| Measurement functions |
|
THD, SINAD |
| Measurement range |
|
–50 dB to 0 dB (THD) |
| 0 dB to 50 dB (SINAD, AM) |
| 0 dB to 40 dB (SINAD, FM) |
| Display resolution |
|
0.1 dB |
| Measurement uncertainty |
|
1 dB (nom.) |
| AF frequency range |
|
20 Hz to 100 kHz (nom.) |
1 Min. and max. detectable audio frequency and harmonics depend on the demodulation bandwidth and audio filter settings.
2 Modulation frequency 1 kHz sine, AM modulation depth 50 %, carrier level 0 dBm, center frequency = 499 MHz, reference level 6 dBm, demodulation bandwidth = 20 kHz, SNR > 60 dB, audio filter = bypass.
3 Modulation frequency 1 kHz sine, FM-deviation = 75 kHz, carrier level 0 dBm, center frequency = 499 MHz, reference level 6 dBm, demodulation BW = 300 kHz, SNR > 60 dB, audio filter = 1/10, deemphasis = off. |
| Measurement of digital modulation signals (ASK, FSK) |
| Center frequency |
|
10 MHz to 4 GHz |
| Demodulation bandwidth |
|
400 Hz to 2 MHz auto-set corresponding to signal and demodulation bandwidth requirements |
| Display |
ASK diagram |
eye diagram, symbols, modulation depth, modulation error |
| ASK numerical results |
carrier power, carrier frequency error, modulation depth and index, modulation error |
| FSK diagram |
eye diagram, symbols, modulation deviation, modulation error |
| FSK numerical results |
carrier power, carrier frequency error, frequency deviation, modulation error, magnitude error |
| Demodulation parameters |
| Modulation and demodulation filters |
transmit filter |
root raised cosine (RRC) |
| raised cosine (RC) |
| Gaussian (GAUSS) |
| unfiltered 5 |
| (measurement and reference filters are internally adapted to signal parameters) |
| Points/symbol |
|
4, 8, 16 internally adapted to signal parameters |
| Filter length |
|
internally adapted to signal parameters |
| Demodulation length |
|
20 symbols to max. 1000 symbols (at 4 points/symbol) |
| Carrier power |
| Carrier power measurement accuracy |
|
add 0.2 dB, see section Level measurement uncertainty |
| Carrier power range |
|
-30 dBm to +20 dBm (nom.) |
| Display resolution |
|
0.1 dB |
| ASK demodulation 6 |
| Measurement range |
symbol rate |
1 kHz to 100 kHz (nom.) |
| modulation depth |
5 % to 95 % (nom.) |
| Modulation depth uncertainty |
|
±(4 %) (nom.) |
| Display resolution |
|
0.1 % |
| FSK demodulation 7 |
| Measurement range |
symbol rate |
1 kHz to 100 kHz (nom.) |
| frequency deviation |
1 kHz to 400 kHz (nom.) |
| symbol rate |
| 1 kHz to 20 kHz |
1 ≤ beta 9 ≤ 20 |
| > 20 kHz to 50 kHz |
1 ≤ beta ≤ 8 |
| > 50 kHz to 100 kHz |
1 ≤ beta ≤ 4 |
| Accuracy |
|
± (4 %) (nom.) |
| Display resolution |
|
0.1 Hz |
5 Reference signal is generated with a Gauss filter, BT = 3.
6 ASK modulation index 50 %, symbol rate = 100 kHz, Gauss BT = 1.0, modulation signal PSBS.
7 FSK modulation deviation 100 kHz, symbol rate = 100 kHz, Gauss BT = 1.0, modulation signal PRBS.
9 Beta is the ratio of frequency deviation to symbol rate. |