Radar level gauge with dielectric rod connection

A radar level gauge using electromagnetic signals to determine a filling level of a product in a tank, comprising:

• a first electronics unit comprising a first mounting portion and a first circuitry portion, said first circuitry portion including first transceiver circuitry for transmitting and receiving electromagnetic signals, first processing circuitry connected to said transceiver circuitry and adapted to determine said filling level based on a relation between transmitted and received signals, and a first directional coupler;
• a second electronics unit comprising a second mounting portion and a second circuitry portion, said circuitry portion including second transceiver circuitry for transmitting and receiving electromagnetic signals, second processing circuitry connected to said transceiver circuitry and adapted to determine said filling level based on a relation between transmitted and received signals, and a second directional coupler;
• wherein each electronics unit provides a functionally independent measurement channel;
• a signal propagation device arranged to direct electromagnetic signals into said said tank and to return electromagnetic signals reflected from said tank;
• and
• a wave guiding structure arranged to guide said electromagnetic signals between said electronics unit and said signal propagation device, said wave guiding structure comprising a rod of a dielectric material, a portion of said dielectric rod extending outside said tank,
• wherein each electronics unit is detachably mounted on said dielectric rod, said dielectric rod extending through an opening in said first mounting portion so as to be at least partially surrounded by said first mounting portion, and said dielectric rod extending through an opening in said second mounting portion so as to be at least partially surrounded by said second mounting portion,
• wherein said first and second electronics units are arranged axially separated along said dielectric rod, and
• wherein said first mounting portion is arranged to secure said first circuitry portion relative said dielectric rod so that said first directional coupler is in a position to couple signals between said first transceiver circuitry and said dielectric rod, and
• wherein said second mounting portion is arranged to secure said second circuitry portion relative said dielectric rod so that said second directional coupler is in a position to couple signals between said second transceiver circuitry and said dielectric rod,
• wherein said dielectric rod is adapted to act as a surface wave guide.