SWRA682 December   2020 CC1310 , CC1312PSIP , CC1312R , CC1314R10 , CC1350 , CC1352P , CC1352P7 , CC1352R

 

  1.   Trademarks
  2. 1 Introduction
  3. 2 Recommended Test Setup
  4. 3 Overrides
  5. 4 Find the Needed RX BW
  6. 5 How to Set the Deviation
  7. 6 Theoretical Sensitivity
  8. 7 Determine AGC_REF Level
  9. 8 Determine Anti-Aliasing BW
  10. 9 Determine PA Ramp Settings
  11. 10Intermediate Frequency (IF)
  12. 11LNA Ib Offset
  13. 12Sensitivity and Selection of Sync Word
  14. 13Narrowband
    1. 13.1 Frequency Offset Tolerance
    2. 13.2 Low Datarate
    3. 13.3 Phase Noise
  15. 14RSSI Offset

10 Intermediate Frequency (IF)

Most PHYs uses the default IF frequency. The default frequency is dependent on the RX BW and is given in the Receiver Bandwidth Settings table in the device-specific Technical Reference Manual (TRM). In some cases it could be a benefit to use a different IF than the default. The IF frequency is set through CMD_PROP_RADIO_DIV_SETUP.intFreq . A lower IF can potentially improve blocking as a lower anti-aliasing BW can be used.

The .intFreq can be calculated as dec2hex(IF frequency*4096/1e6).

Good design practice: RXIF - deviation + guard band > DC. Guard band is needed to keep the "lower end" of the RX BW sufficiently above DC. There is a DC filter that removes 1/f noise, and the guard band is needed so that the DC filter does not remove any of the signal.