WIDEBAND INSTANTANEOUS FREQUENCY MEASUREMENTS (IFM) USING SAW DEVICES.

A popular method of performing frequency measurement is by using the autocorrelation of the signal to be measured with a delayed (fixed delay) version of the same signal. A disadvantage of this approach is the ambiguity in the result unless the input bandwidth is limited. Instead, a variable delay line controlled by a feedback arrangement is proposed. This approach using SAW components for the voltage controlled delay line (VCDL) is shown to provide a wide-band measurement with no ambiguity. Systems with different feedback loop filters are analyzed and compared.