2. -  Standard Software

The raw acoustic spectra are computed using a Fast Fourier Transform (FFT).

Most of the processing is done by software thus dramatically reducing the amount of transceiver hardware.

The software also handles the transceiver relays which are connected to the different transducers of the antenna and perform the beamforming along the 5 (up to 9) axes (1 vertical, 4 -up to 8- tilted).

In the receive mode, the backscattered signal is first processed through 1024 frequency point FFT’s.

All REMTECH Doppler Sodar systems are provided with the following features :

-   Frequency Coded Transmission

-   Fast Fourier Transform Doppler Detection by software

-   Automatic Fixed Echo Detection

-   Data output on hard disk, CD-RW/DVD-ROM, Display, printer and modem

-   Automatic real-time data validation

-   Standard display and recording of:

.    echo strength

.    wind speed

.    wind direction

.    vertical speed.

3. -  Some Software Options

.    Sigma W Software

Computes the vertical wind speed standard deviation in real time. Sigma w is corrected for individual measurement error using the frequency coding approach.

.    Sigma Theta Software

The standard deviation of horizontal wind direction is computed in real time.

.    Automatic Inversion Detection Routine

This routine uses pattern recognition algorithms which are applied to backscattered signal, wind components and turbulence vertical profiles. The output is a direct read-out of inversion height accomplished in real time. A success rate greater than 90% is experienced at most sites. This routine requires sigma w and sigma theta software options to function.

.   Automatic Mixing Height Calculation

Provides an estimation of the mixing height in real time by using a spectral analysis of the vertical component time series at different levels.

Needs sigma w and sigma theta routines.

.    Automatic Stability Classification Routine

This is a real time direct determination of stable/neutral/unstable categories as a function of height and time. Pattern recognition algorithms using echo profiles, wind, wind shear (pseudo "Bulk Richardson" approach).

Needs sigma w, sigma theta and automatic inversion detection routines.

.    Temperature Lapse Rate Estimation

Provides an estimation of the temperature lapse rate in real time. Requires sigma w, sigma theta, and automatic inversion detection routines.