ODUNGE STANS
5 days ago
Assuming you were to measure a frequency deviation of FM wave, explain how you will achieve this using a spectrum analyzer.
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Google Gemini AI
5 days ago
Materials:
- Spectrum analyzer
- FM signal generator
Procedure:
1. Set up the FM Signal Generator:
- Configure the FM signal generator to output the desired FM wave.
- Set the carrier frequency, modulation frequency, and modulation index.
2. Connect the Signal Generator to the Spectrum Analyzer:
- Connect the output of the FM signal generator to the input of the spectrum analyzer.
3. Configure the Spectrum Analyzer:
- Set the frequency range to encompass the carrier frequency and sidebands.
- Set the resolution bandwidth (RBW) to a narrow value (e.g., 10 kHz).
- Set the video bandwidth (VBW) to a wide value (e.g., 100 kHz).
4. Identify the Carrier and Sidebands:
- The carrier will appear as a peak at the carrier frequency.
- The sidebands will appear symmetrically around the carrier.
5. Measure the Frequency Deviation:
- Determine the frequency separation between the carrier and the upper sideband (or lower sideband).
- Double this value to obtain the frequency deviation.
Formula:
```
Frequency Deviation = 2 × (Frequency Separation between Carrier and Sideband)
```
Example:
If the frequency separation between the carrier and upper sideband is 15 kHz, then the frequency deviation is:
```
Frequency Deviation = 2 × 15 kHz = 30 kHz
```
Note:
- The RBW and VBW settings can affect the accuracy of the measurement. A narrower RBW will provide a more precise measurement, but will also reduce the signal-to-noise ratio. A wider VBW will improve the signal-to-noise ratio, but may reduce the measurement resolution.
- The modulation index of the FM wave will also affect the frequency deviation. A higher modulation index will result in a greater frequency deviation.
- Spectrum analyzer
- FM signal generator
Procedure:
1. Set up the FM Signal Generator:
- Configure the FM signal generator to output the desired FM wave.
- Set the carrier frequency, modulation frequency, and modulation index.
2. Connect the Signal Generator to the Spectrum Analyzer:
- Connect the output of the FM signal generator to the input of the spectrum analyzer.
3. Configure the Spectrum Analyzer:
- Set the frequency range to encompass the carrier frequency and sidebands.
- Set the resolution bandwidth (RBW) to a narrow value (e.g., 10 kHz).
- Set the video bandwidth (VBW) to a wide value (e.g., 100 kHz).
4. Identify the Carrier and Sidebands:
- The carrier will appear as a peak at the carrier frequency.
- The sidebands will appear symmetrically around the carrier.
5. Measure the Frequency Deviation:
- Determine the frequency separation between the carrier and the upper sideband (or lower sideband).
- Double this value to obtain the frequency deviation.
Formula:
```
Frequency Deviation = 2 × (Frequency Separation between Carrier and Sideband)
```
Example:
If the frequency separation between the carrier and upper sideband is 15 kHz, then the frequency deviation is:
```
Frequency Deviation = 2 × 15 kHz = 30 kHz
```
Note:
- The RBW and VBW settings can affect the accuracy of the measurement. A narrower RBW will provide a more precise measurement, but will also reduce the signal-to-noise ratio. A wider VBW will improve the signal-to-noise ratio, but may reduce the measurement resolution.
- The modulation index of the FM wave will also affect the frequency deviation. A higher modulation index will result in a greater frequency deviation.
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