Special Issues at Low frequencies: Dynamic (ctd.)
•Power variations may be > 20 db/sec.
•Implications:
–High dynamic electronics needed
•Automatic attenuators or very fast AGC may be be needed in narrow band channels.
•Correlation is better made by 1 bit correlator +power measurement (or many bits correlator - challenging ?)
–If a spectrum is computed before correlation, it will have the dynamic of narrow channels (neglecting interferences)
•Note: Dynamic on images (Tb) may be much higher