Ultrasonic level measurement and DATEM digital echo processing Digital Adaptive Tracking of Echo Movement

Features
• Superb echo discrimination
• Most accurate ultrasonic level measurement system in the world
• Easy application set-up
• Locks onto the true echo, ignores interference from other signals
• Trouble free operation

As a technique, ultrasonic level measurement has been around for decades, working on the ‘time of flight’ principle that if you know the speed of sound, then the time that a sound pulse takes to travel from a transducer and back again may be used to calculate the distance that pulse has travelled. Divide by two and you have the distance to the ‘target’.

Early analogue instruments, while they were fine for simple applications, were easily ‘confused’, they had to be carefully set up and the path to the target had to be clear and unobstructed, because the success of the measurement depended on the true echo returning from the target being ‘louder’ than any competing echo. As time went on, more sophisticated digital echo processing allowed for more discrimination of echoes, but still depended on blocking out competing echo traces and using software to identify the true echo from among the competing traces.

Pulsar pioneers the way in ultrasonic level echo processing technology.

As microprocessors have improved, Pulsar has continued to develop and improve echo processing software, so that it is now possible to make successful measurements in situations that would have been far beyond the units of even a decade ago. Pulsar’s echo discrimination system, DATEM, works on the basis that it first identifies the true, moving echo from the background noise, then follows it, ignoring all of the competing echoes as it does, so DATEM allows Pulsar equipment to work in a cluttered sewage wet well, or in a noisy stone silo, an agitated tank or even through a grid. DATEM also looks for echoes within a very small frequency range, which helps to make it especially good at ignoring both acoustic and electrical noise. The high power of Pulsar’s dB series transducers makes sure that all the echoes from an application can be easily monitored. The end result is highly reliable level measurement in applications which previously could not be considered.