| ??? 06/10/09 12:17 Read: times |
#165986 - Suggestions Responding to: ???'s previous message |
The HART signal will probably have good frequency accuracy as the HART modem chips (such as the Maxim DS8500) will use a stable oscillator, and guarantee phase continuity. The electrical environment that of a HART connection will be industrial and noisy, so you will need proper filtering in the analogue domain so that the noise doesn't swamp the ADC input range. I would also suggest increasing the ADC sampling rate to make the design of the nyquist filter easier.
Detecting a frequency in a set of digital samples is a textbook DSP problem. |
| Topic | Author | Date |
| FSK / HART - Demodulation on ADC | 01/01/70 00:00 | |
| Unknown phase. | 01/01/70 00:00 | |
| back in the days of tape cassettes ... | 01/01/70 00:00 | |
| Goertzel algorithm to detect tones | 01/01/70 00:00 | |
| /Goertzel_algorithm is a good tone FFT decoder | 01/01/70 00:00 | |
Thanks - I'll have a look | 01/01/70 00:00 | |
| Suggestions | 01/01/70 00:00 |