Because the log-domain circuit is based on the log-exponential companding characteristics of transistors, and the noise sources exist in the transistor抯 interior, therefore, this gives rise to a phenomenon called signal-noise inter-modulation, which is contrasted with the constant noise in linear and non-companding circuits.
First based on existed methods of the realization of CWT, we present a method using log-domain circuits to improve system capability, that is to say, by using log domain technology to design the function modules in existed architectures we realize the purpose of improvement of system performance.
In the circuits proposed presently for implementation of continuous wavelets transforms(CWT),we take out several crucial analog devices from them and discuss the relationships between these devices and log-domain circuits.
A CWT was realized by using log-domain circuits. An analogue CMOS high-frequency continuous wavelet transformation circuit has been proposed to perform a time-frequency decomposition of a high-frequency input signal.