FIELD: physics.
SUBSTANCE: device for level measurement of fluid situated under a dielectric constant gas with the constant value within given range. The device includes: microwave transmitter emitting given mode into tube through gas in the direction of fluid surface; microwave receiver for the signal reflected off the fluid surface and propagating back through the tube; and signal processing device for calculating fluid level on the base of transmitted and reflected signal propagation speed data. Actually, in order to eliminate impact of dielectric constant of the gas above the fluid on the calculated level value, the transmitter is enabled to transmit microwave signal in a definite frequency range, where group propagation velocity of a microwave signal in the form of given mode is basically independent of dielectric constant within definite value range.
EFFECT: elimination of gas dielectric constant impact on the calculated level value.
42 cl, 12 dwg
