[ath9k-devel] ath9k: spectral scan -vs- channel state information

Hi

I am having some trouble understanding the difference between 
channel state information (often requested on the mailing list)
 and what is currently available via spectral scan.


My understanding is as follows;
- spectral scan (once triggered via the debugfs) logs 
channel state estimation for each of the 56 ofdm subcarriers
 (HT20 case). In the spectral code (for ath9k), the channel state 
info is the I and Q values for the subcarriers.
For ath9k, the bulk of the code is in ath_process_fft 


Bits I dont understand :
Can channel state information be collected on a more general 
basis ? --- for example for each phy packet received.

Also, the calibration (ar9003_calib) seems to gather I and Q 
data also... but its not clear when this is run/collected and used.

Any help appreciated....