Other Parts Discussed in Thread: CC1175
We'd made some communication tests with CC1120 recently.
We tried several communication baudrate and found that at different baudrate it is better to use different preamble length. When preamble length was wrong, packet loss will happen.
The configuration of our system is as below:
A:
- Xtal Frequency 32 MHz
- Modulation Format 2FSK
- Symbol Rate 38.4 Ksps
- Deviation 19.2 KHz
- Rx Filter BW 125 KHz
- Sync Word Length 16 bit
- Zero-IF
- AGC_WIN_SIZE 64 samples
- UPSAMPLER_P P = 8
The preamble length 4 Bytes seems to be the best.
B:
- Xtal Frequency 32MHz
- Modulation Format 2FSK
- Symbol Rate 76.8Ksps
- Deviation 38.4KHz
- Rx Filter BW 200KHz
- Sync Word Length 16bit
- Zero-IF
- AGC_WIN_SIZE 128 samples
- UPSAMPLER_P P = 4
The preamble length 12 Bytes seems to be the best.
Longer preamble means more protocol overhead, hence we want to get the minimum usable preamble length.
What is related to the preamble length configuration?
Thanks.
KinyAnderson