Other Parts Discussed in Thread: CC1190, CC1120
Tool/software:
Hi all,
I'm currently working on an RF application using the CC1120 transceiver with the CC1190 range extender (booster pack), and I need some clarification regarding the AGC_CS_THR (Carrier Sense Threshold Configuration) register.
According to the [CC1120 datasheet], this register defines the carrier sense threshold in dBm using a two’s complement format with 1 dB resolution. I have a few questions:
1. How do I configure AGC_CS_THR properly?
- I see that this value determines whether the channel is considered busy or idle based on RSSI.
- The default value in SmartRF Studio seems to be
0x19(decimal 25), which corresponds to -77 dBm (25 - 102 = -77 dBm). - What are the key considerations for setting this threshold optimally for my application?
2. How does this register affect RF transmission and reception?
- Will setting a higher threshold (e.g., -77 dBm) cause the receiver to ignore weaker signals?
- Will setting a lower threshold (e.g., -100 dBm) cause it to treat noise as activity and potentially avoid transmitting?
- How does this value impact Listen Before Talk (LBT) or CSMA/CA functionality?
3. Any specific guidance when using CC1190 with CC1120?
- Since CC1190 provides additional gain in the RX path, should the
AGC_CS_THRvalue be adjusted accordingly to account for increased sensitivity? - Are there any recommended values for use cases with high receiver gain and short-range or long-range links?
