CC1120: How can I expand the RX window?

Danilo A.

Part Number: CC1120

Hi Team,

We would like to ask for your assistance to the customer's inquiry below.

I have a 169Mhz radio (CC1120) set to a frequency of 169.406250Mhz. I have to receive data with a tolerance of +/- 1.5Khz. By doing some tests I have verified that up to +/- 700Hz I receive the data correctly, but not beyond that. How can I expand the RX window?

Thank you for your support!

Regards,

Danilo

over 3 years ago

0 RGW over 3 years ago

TI__Mastermind 29570 points

Hi,

To change the Rx bandwidth, then this is mainly the CHAN_BW register and also IQIC register.

In SmartRF studio for CC1120 Generic 169 MHz PHY, there are three PHYs available with different Rx bandwidths: 10 kHz, 25 kHz and 50 kHz.

Which bandwidth do you use today ?

Regards,

Richard

0 TER over 3 years ago in reply to RGW

TI__Guru**** 317180 points

Also, look into the "Feedback to PLL" feature.

0 Luca Filippucci over 3 years ago

Prodigy 100 points

Hello,
the bandwidth is 10Khz.

IQIC = 0xC6
CHAN_BW = 0x14

As indicated in Smart RF Studio

I also checked the "Feedback to PLL" features and the FREQOFF_CFG register is disabled (0x22).


Regards.

0 RGW over 3 years ago in reply to Luca Filippucci

TI__Mastermind 29570 points

Hi,

Use the same settings as used for the CC1120 169 MHz Generic PHY settings with 25 kHz Rx bandwidth in SmartRF studio.

Let us know if this resolve the issue.

Regards,

Richard

0 Luca Filippucci over 3 years ago in reply to RGW

Prodigy 100 points

Hi,
I configured the CHAN_BW register as expected for 25Khz and now the offset

has expanded as my application needed.


Thanks for the support.

Regards
Luca

Sub-1 GHz

Sub-1 GHz forum

CC1120: How can I expand the RX window?