In a message dated 3/31/2007 17:29:21 Pacific Daylight Time, [EMAIL PROTECTED] writes:
Multiplying the 2 signals is essential as the non correlated components of the 2 signals will then average to zero (for infinite measurement time) whilst the correlated components of the 2 signals will not. A cross spectral analysis is somewhat analogous to using an array of single frequency correlators. The residual noise decreases as the integration time increases. When multiple power spectra are averaged the noise floor will decrease as 1/n where n is the number spectra averaged. Bruce Hi Bruce, got it, thanks. But isn't a signal source typically single-ended, and has a 50 Ohm source impedance which creates noise? Wouldn't we need a source with 1 Ohm source impedance even if the measurement system is cross-correlated? Would a differential source suffice? bye, Said ************************************** See what's free at http://www.aol.com. _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
