CHIRP DESIGN FOR ACOUSTICAL SYSTEM-IDENTIFICATION

A repeated linear chirp (choip) is a broadband waveform with the lowest possible peak to rms amplitude ratio (peak factor) also having the property that the frequency band for its power concentration (power band) can be specified. A low peak factor is desirable to maximize signal power while avoiding clipping or saturation effects. The capability to concentrate power is desirable to maximize the signal to noise ratio. Choips, having both properties, make reduced measurement time possible in practical system identification relative to impulse and maximum length sequence waveforms. This is particularly useful with time-varying systems. Choips for use with analog-digital data acquisition systems can be designed easily and quickly. They can be designed to minimize leakage and aliasing. For application to a typical acoustical system, over 99% of a choip's power can be concentrated in a specified power band.