Non-contact radar discharge system - RQ-30

The flow velocity and the water level are measured separately and the discharge is calculated by combining the two measurements. The RQ-30 measurement system is a combination of two sensors for the measurement and an integrated processor to calculate the quantity of discharge. The measurement of the flow velocity is based on the principle of the frequency shift due to the Doppler effect.

The radar sensor is installed pointing in a defined angle on the water surface. Via the send and receive antenna a constant frequency of 24 GHz is sent. This signal is partly reflected at the water surface and returns with a specific shift to the antenna. With support of spectral analysis, filters and statistical methods the velocity is determined.

The water level is measured on the principle of a transit time measurement. The radar sensor transmits defined impulses of a length in the low microsecond range vertically to the water surface. There the signal is reflected back to the radar sensor, where it is received. The time span between the transmission and the receiving of the impulse is measured, which is proportional to the distance between the sensor and the water surface.

The discharge Q is calculated corresponding to the continuity equation by multiplying the area of the cross section and the mean velocity. The area of the cross section is deviated from the profile at the measurement site and the actual water level.

• Waterproof IP 68
• Fast measurement and calm measuring signal
• Dynamic of measuring process
• Automatic and internal inclination sensor
• Flow direction recognition
• Small, compact design
• External input for additional sensors e.g. water temperature
• Digital output for alarm systems or activation of sampler
• High velocity measurable - up to 15 m/s
• Easier integration and update possibility
• More interfaces - SDI 12, RS 485, analog
• Bed river changes measurable
• Low power consumption

• Sommer_NonContactRadarDischargeSystem_RQ30_b.pdf

• Sommer_TechnicalInformation_RQ30.pdf