DOP3010 overview

The DOP3010 includes all the available software packages of the DOP3000 series of ultrasonic Doppler velocimeter, such as the variable emitting frequency, resolution, number gates, and many others capability. This places this instrument on the top of Signal Processing's technology. Moreover, the instrument always keep the possibility to install any future software packages.

This multiplexer allows to measure velocity profiles or other data issue from different probes one after the other. Up to 10 different transducers can be connected. During the acquisition process in multiplexer mode, the multiplexer switches from one channel to the other after the measurement of a user's defined number of data profiles. As all the 10 channels are totally independent, each channel can accept different probes and different set of parameters or settings, such as different emitting frequencies, PRF, number of channels, TGC, etc...

This multiplexer has been designed to enable easy flow mapping studies, in case of stationary velocity field or when only mean values of the velocity field are requested. For non stationary velocity field, the UDV 2D/3D controller is recommended.

This 10 channels multiplexer increases the application field and the flexibility of the DOP3010.

UDV 2D or 3D Ultrasonic Doppler Velocimetry measuring technique is a method that enables the measurement of two velocity components (Vx and Vz) or three velocity components (Vx, Vy and Vz) simultaneously along a line. UDV 2D/3D has all the advantages of classical ultrasonic Doppler velocimetry, such as the capacity to realize measurements in non translucid liquids. One of the most interesting property of this technique compared to other techniques is that it can measure simultaneously more than one velocity component in real time. Only few tens of milliseconds are necessary to compute and display a complete 2D or 3D velocity field. This is not> possible by means of use of the 10 channels multiplexer.

The DOP3010 contains a special internal controller that manages the way the emitted burst is send and the way the echoes are received from the 2 or 3 receivers.

Note that in order to be able to use this hardware an additional software package must be purchased and installed.

Unlike the DOP2000, the DOP3000 series has no embedded computer. An external PC desktop or laptop controls the instrument through its built-in USB interface. This flexible solution allows to use the instrument in all kinds of situations.

Based on very simple indications given by the user, such as the depth of measure along the ultrasonic beam and the maximum velocity to be measured, the brand new UDOP software delivered with the DOP3000 automatically computes most operating parameters (TGC, PRF, scale factors, number of emissions per profile). Tedious manual setting can therefore be avoided. Of course, advanced users can still fine-tune all these parameters or bypass this automatic mode.

The DOP3000 series also lets the user to set a quality factor of the measure, which defines an optimal trade-off between signal to noise ratio and sampling rate.

The sensitivity is a very important parameter because it influences the range of possible application of the instrument. A high sensitive instrument allows measurements in liquids containing few particles and/or in liquids having high attenuation coefficient. The sensitivity is defined as the minimum instantaneous power of the Doppler echoes from which Doppler information can be extracted and is expressed in dBm (reference power 1mW on a 50 ohm impedance).

Unfortunately, for most ultrasonic Doppler instruments find on the market, any numbers characterizing the sensitivity are not given. This makes the comparison difficult. Signal Processing has a put a lot of effort to offer very high sensitive instruments. This is why when many other instruments failed the DOP3000 series of ultrasonic velocimeter still deliver quality information.

The definition of the thickness of the sampling volumes are not only defined by the ultrasonic burst length as it some times mentioned. This would be the case only if the electronic bandwidth of the instrument was infinite. This is never the case as all ultrasonic instruments owns filters to rejected unwanted noise level. The bandwidth reduction defines the minimum thickness of the sampling volume. In order to realize the best compromise between the noise level and the desired resolution, the DOP3000 series of velocimeter can modify both the burst length and the bandwidth of the receiver stage.

The way we design our velocimeters offers to our customers a very versatile instrument that allows for instance to collect and record raw data. This opens the possibility to evaluate any customer's processing methods and ideas, and therefore to advise them so that they can improve the way they use their DOP velocimeter