A novel signal conditioning system for SODAR

Abstract

The Sonic Detection and Ranging (SODAR) instrument is widely used for measuring the Atmospheric Boundary Layer (ABL). SODAR operates on an acoustic principle and creates an ABL structure using air-backscattered signals. These signals have extremely low amplitude and are highly susceptible to environmental noise. In this paper, a novel signal conditioning circuit with high gain, low noise, and high quality factor Q has been designed for the preamplifier of SODAR. This signal conditioning circuit is comprised of an ultra-low noise amplifier and a dual-amplifier band-pass filter. The designed preamplifier circuit is implemented with SODAR at the CSIR-National Physical Laboratory in New Delhi. The electrical characteristics of the proposed system are compared to the existing design of a single low-noise amplifier and state variable filter. The gain and signal-to-noise ratio performance of the designed preamplifier circuit are significantly improved in comparison to the existing one.