• State
  • Locked Locked
  • Replies 1 reply
  • Subscribers 53 subscribers
  • Views 1083 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CC1121: Data Whitening: cAutomatic Frequency Tracking for FSK modulation Benefits

Zebryk
Expert 1240 points
Part Number: CC1121

Hello,

According to TA, enabling Data Whitening can benefit "automatic frequency tracking for FSK modulation".

Interested in more elaboration on this. Ours is a 4800BPS 2-FSK packet having a relatively long payload.

Does enabling this feature have any downside?

What is the benefit gain in terms of dBm sensitivity at 1% PER?

Does the CC112x series have some Clock Recovery feature AFTER the Preamble and Sync Word(s)?

If so, does that provide compensation for accumulating Bit-to-Bit by Byte timing errors?

Jay Zebryk

  • 0
    TI__Guru**** 317180 points
    - Tracking through a packet requires some '1' <-> '0' transitions
    - Whitening doesn't affect sensitivity/ BER directly but bit errors due to long strings of either '0' or '1' will be avoided.
    - I have found that increasing the FREQOFF.FOC_KI_FACTOR to 0x3 enables the chip to avoid bit errors even for long '0' and '1' sequences.

    If your protocol allows for it, use whitening or other means to avoid long sequences of '1' or '0'. With the default settings I have seen that bit errors starts to occur after ~7-8 bytes with just '1' or '0'.