System and method for determining density of a medium in a tank

摘要

A system and method for determining a density of a non-conducting medium in a tank is disclosed where the relationship between a dielectric constant and a density of the medium is known. The system comprises a transceiver, and a waveguide, the waveguide extends towards and into the medium. The system further comprises a first microwave resonator located along the waveguide. The first microwave resonator has a resonance frequency, which depends on a dielectric constant of a medium surrounding the resonator according to a known relationship, and is arranged to reflect a portion in the frequency domain of a signal being guided along the waveguide. The system further comprises processing circuitry connected to the transceiver and configured to determine the resonance frequency based on a received reflected signal, and to determine a density of the medium at the location of the first microwave resonator based on the resonance frequency.

主权项

1. A system for determining a density of a non-conducting medium in a tank, wherein a relationship between a dielectric constant and a density of said medium is known, and wherein the density is mass per unit volume, said system comprising:
a transceiver configured to generate, transmit and receive a microwave electromagnetic signal comprising frequencies within a predetermined frequency range; a waveguide connected to said transceiver and extending towards and into said medium, arranged to guide a transmitted electromagnetic signal towards and into said medium inside said tank, and to return an electromagnetic signal resulting from a reflection of said transmitted electromagnetic signal; a first microwave resonator having a resonance frequency, and configured to reflect frequencies corresponding to a first bandwidth around said resonance frequency, said first bandwidth being smaller than and within said frequency range, said resonance frequency depending on a dielectric constant of a medium surrounding said resonator according to a known relationship; wherein said first microwave resonator is arranged at a location along said waveguide, and configured to reflect a portion of an electromagnetic signal, in the frequency domain, corresponding to said first bandwidth, when said electromagnetic signal is guided along said waveguide; and processing circuitry connected to said transceiver and configured to: determine said resonance frequency based on a reflected portion of a received signal having been reflected by the first microwave resonator, said processing circuitry being further configured to: determine a density of said medium at the location of said first microwave resonator based on said resonance frequency.