We are using the CC1200 with the following main parameters:
1. Bit rate of data is: >= 500 kbps
2. Modulation format = 4-GFSK.
3. Packet length mode = Infinite , changed to fix when the rest of packet is less 256 Bytes.
4. Deviation :0.3 of the bit rate approx.
5. The protocol: one packet from A to B and then one packet in opposite from B to A and again.
6. The length of preamble : 4 bytes.
In lower than 500 kbps bit rate, the PER is very good.
The problem :
When the auto-cal for FS is turn On, the PER is very bad regardless of the signal level.
But when it turn off, The PER is an acceptable
At rate of 500 kbps with the Modulation format: 2 -GFSK is working fine, even when the auto-cal is On.
Beyond the 500 kbps bit rate , there is not option to work other than 4-GFSK.
Is there any explanation why is it not good working when the auto cal is turn on in 4- GFSK ?
What should be the corrected setting ?
Maybe there is another wrong setting ?
What should by the recommended stability of the oscillator when the auto calibration is turn off ?
By using TCXO of the stability of +- 2 ppm over the temperture range, is good enough to tun off the auto calibration ?
I appreciate your clarification.
B.R.
Yoram