Radar level sensors are becoming the primary option for level measurement in many industries. Few days back Rocksensor India has supplied 58 no. compact radar level transmitter for one of the smart city project in India.


In one of the smart city project, there is a need of reliable continious level measurement of water canal. The water arrives through a large canal supplied by reservoirs. Reservoir's flow rate is controlled by measuring the canal level. The measurement is critical, and the operators had experienced difficulty with other level sensors in the past when the weather was bad.


The consumer prefers a compact, integrated instrument. The major issue is that compact instruments typically do not operate effectively in all weather situations. In the winter, the instrument needs to run at (-)10°C, while in the summer, it must operate at 60°C in direct sunlight. Most instruments usually fail if they are exposed directly to the sun due to their temperature limitations for an extended period of time. Protection against the environment is a big consideration too.


Rocksensor India suggested the use of compact radar level transmitters that are unaffected by environmental conditions such as rain or wind. The radar level transmitter sends continuous level measured, to the system, which controls reservoir flow rates. With RLT6400C the operator can see what's going on locally and get a convenient indication of the level. There is no extra enclosure needed or required with the RLT6400C, as it is approved to work outside in all weather situations, including heavy rain.

Radar level transmitters used for level measurements in different applications are of two types:

Contact Type Transmitter

Non-Contact Type Transmitter

Working Principle

Radar level transmitters work on one of two working principles:
• Frequency-modulated continuous wave (FMCW)
• Time-of-flight (ToF)

Time of Flight

The Time-of-Flight principle (ToF) is a method for measuring the distance between a sensor to the product surface, based on the time difference between the emission of a signal and its return to the sensor, after being reflected by product surface.

The microprocessor identifies the echo and calculates the time it took for the signal to return.

Various types of signals can be used with the Time-of-Flight principle, the most common being sound and light.

Frequency Modulated Continuous Wave

Frequency Modulated Continuous Wave (FMCW) radar is a type of radar where the frequency of the transmitted signal is continuously varied at a known rate over a defined period of time. The reflected frequency signal is received by the radar and then compared. The difference between the transmitted and reflected signals is directly proportional to the time of flight, which is directly proportional to the range.

Key Industries

The radar level transmitters being accurate are used in different critical engineering environments. Some of the industrial applications of these level sensors are as follows.


Mining Industry:

In the mining industry, these transmitters are used to check the depth or length of mines, as well as the level of the ore's surface. Due of frequency continuity, FMCW radar level transmitters are generally utilised here. When the only accessible medium is air, ultrasonic radar technology may be used.


Boiler Engineering:

Boilers are potentially hazardous equipment of machinery. Due to the extremely high water and stream temperatures, measuring fluid level is extremely challenging. In such cases guided wave radar level sensors are used. Their guided probes are immune to high temperatures and have no effect. Therefore, they are utilized in boiler applications as fuel level or fluid level indicators.


Aeronautics Industry:

In automobile industries, the fuel levels are frequently measured by using contact type level indicators. However, a fuel storage system is a little complex. Therefore, radar-level transmitters are used.


Paper and Pulp Industry:

In the paper and pulp industry level of slurry, water and storage tanks, can be measure using these level transmitters. As Guided probes can be utilised in chemical environments, therefore it is a suitable choice in paper and pulp industry.


Bore Digging Technology:

In the bore digging process, the level measurement devices are exposed to mud, slurry, and under-surface gases throughout the process. These level indicators are used to check surface levels in such instances.