SPRACF4C June 2018 – January 2023 AWR1243 , AWR1443 , AWR1642 , AWR1843 , AWR1843AOP , AWR2243 , AWR2944 , AWR6843 , AWR6843AOP , IWR1843 , IWR6443 , IWR6843 , IWR6843AOP
The HPF1 and HPF2 high pass filters are only calibrated once, at boot time. The RX IFA square wave loopback is used to feed a known tone at the IFA input, and the ADC output’s FFT component at the same frequency is measured. The filter is tuned to achieve the desired attenuation at the desired cutoff frequency.