Comparison of measurements of wind by means of a sodar and the device MTP-5
- Measurements of a sodar depend on humidity of air. During strong rainfall reliability of data falls.
- data from the MTP-5 device don't depend on humidity of air.
- Sodar measures average wind.
- MTP-5 also measures average wind, but, allows to trace a rush if he was, in 5 minutes after the previous measurement.
- When the pulsing acoustic signal (sound) passes through the atmosphere, he meets vortex streams on the way that leads to dispersion
energy of sound waves in all directions. Part of a signal is reflected and, thanks to Dopler's effect, is measured.
When the reflecting signal moves towards the antenna of a sodar, the frequency of a scattered signal will be higher,
than the frequency of the transmitted signal. On the contrary, when the target moves away from the antenna, the frequency of a scattered signal will be lower.
Therefore, in this case vertical, but not horizontal wind is defined.
- MTP-5 measures horizontal wind.
- Sodar transmits and accepts sound signals within a specific frequency strip. Any extraneous noise within this strip influences
on the received signal, therefore, errors of measurements aren't excluded.
- Accuracy of measurements of the MTP-5 doesn't depend on noise and can work in any place.
- Action height. As force of the reflected signal usually strongly changes with height, weaker signal from higher layer of the atmosphere,
it can be more likely lost because of extraneous noise. Don't specify exact height in many modifications,
and only phrase "... depends on meteoconditions".
- The MTP-5 measures data at the heights from 0 to 1000 m and his measurements don't depend on meteoconditions.
- Hindrances from the land surface. Influence of this factor is especially strong when a side component of a signal of a sodar from the transferring antenna
is reflected close located objects – buildings, trees, pipes, etc.
This effect can suppress the signal disseminated by the atmosphere and lead to obtaining the distorted data with an opposite inclination of characteristics of wind.
- The MTP-5 performs measurements on any landscape, but, of course, the accuracy of measurements will be higher on open areas.
- Sodar consists of the transferring and reception antenna.
- The MTP-5 contains only the reception antenna that allows not to load the atmosphere with excess noise and is more favorable for environment and the operators performing measurements.
- Monostatic sodar allows to obtain a lot of information on a condition of the atmosphere.
It is intensity, or signal amplitude which characterizes a temperature profile.
- The MTP-5 also performs measurement of temperature profiles that will also allow to estimate of atmospheric pressure and relative humidity.