Abstract: A radar level gauge comprising transceiver circuitry, a propagation device and processing circuitry for determining a value of the process variable based on a relationship between a transmit signal and a return signal. The gauge has a DC/DC converter connected to a power supply interface, and configured to convert a first voltage to a second voltage, lower than the first voltage, and an energy storage. The gauge further has a switch, connected between the DC/DC converter and the energy storage, the switch having a non-conducting state for disconnecting the energy storage from the DC/DC converter when the transceiver circuitry is active, and a conducting state for connecting the energy storage to the DC/DC converter only when the transceiver circuitry is inactive.

Abstract: A radar level gauge comprising a housing enclosing a compartment providing explosion proof protection, RLG circuitry located inside compartment, which circuitry is incompatible with intrinsic safety requirements, and a signal propagation device located outside the compartment. The housing has an explosion proof first signal passage providing a transmission line for the microwave transmit signal, and an explosion proof second signal passage in providing a two-wire interface for electrically conductively connecting the radar level gauge to an intrinsically safe system located externally of the radar level gauge. Further, the RLG includes an electrical barrier connected between the RLG circuitry and the two-wire interface, the electrical barrier preventing energy and/or thermal energy in the RLG circuitry from compromising the intrinsic safety of an intrinsically safe system connected to the two-wire interface.

Abstract: A radar level gauge comprising a housing enclosing a compartment providing explosion proof protection, RLG circuitry located inside compartment, which circuitry is incompatible with intrinsic safety requirements, and a signal propagation device located outside the compartment. The housing has an explosion proof first signal passage providing a transmission line for the microwave transmit signal, and an explosion proof second signal passage in providing a two-wire interface for electrically conductively connecting the radar level gauge to an intrinsically safe system located externally of the radar level gauge. Further, the RLG includes an electrical barrier connected between the RLG circuitry and the two-wire interface, the electrical barrier preventing energy and/or thermal energy in the RLG circuitry from compromising the intrinsic safety of an intrinsically safe system connected to the two-wire interface.

Abstract: A radar level gauge for determining a filling level of a product in a tank, comprising a volatile high-speed working memory, a first processing unit connected to the volatile high-speed working memory, the first processing unit having an active mode in which the first processing unit is turned on and accesses the working memory, and an inactive mode where the first processing unit is turned off, memory loading functionality, configured to transfer software code from a non-volatile memory into the volatile high-speed working memory, wherein the memory loading functionality is further configured to divide the software code into a plurality of smaller portions, and transfer one such smaller portion at a time. By dividing the software code which is to be transferred into a plurality of smaller portions, the energy required to complete transfer of one such smaller portion can be sufficiently small to allow energy storage capacity of feasible size and cost.

Abstract: A radar level gauge for determining a filling level of a product in a tank, comprising a volatile high-speed working memory, a first processing unit connected to the volatile high-speed working memory, the first processing unit having an active mode in which the first processing unit is turned on and accesses the working memory, and an inactive mode where the first processing unit is turned off, wherein the working memory has a memory preserving low power mode during periods when the first processing unit is in inactive mode, and an auxiliary power connection configured to provide power to the volatile high-speed working memory from the power management circuitry during the low power mode, wherein the processing circuitry is designed to reduce any leakage currents from the volatile high speed memory to the other parts of the processing circuitry in the memory preserving low power mode.

Abstract: A radar level gauge for determining a filling level of a product in a tank, comprising a volatile high-speed working memory, a first processing unit connected to the volatile high-speed working memory, the first processing unit having an active mode in which the first processing unit is turned on and accesses the working memory, and an inactive mode where the first processing unit is turned off, memory loading circuitry, separate from the processor, configured to transfer software code from a non-volatile memory into the volatile high-speed working memory while the processor is in inactive mode, and an auxiliary power connection configured to provide power only to the volatile high-speed working memory and the memory loading circuitry. With this design, the memory loading circuitry and working memory can be powered separately, thereby allowing loading of software code from the non-volatile memory into the volatile high-speed working memory without activating the relatively power-hungry processor.

Abstract: A radar level gauge system controllable between a measurement state and a signal processing state. In the measurement state a first timing signal circuit is enabled, a microwave signal source generates a transmit signal with a time-varying frequency being related to first timing signals from the first timing signal generating circuitry, and a sampler samples a mixer signal at sampling times related to the first timing signals. in the signal processing state, the first timing signal circuit is disabled, and a signal processor determines the filling level based on the sampled values of the mixer signal using second timing signals from a second timing signal generating circuit.

Abstract: A radar level gauge comprising transceiver circuitry, a propagation device and processing circuitry for determining a value of the process variable based on a relationship between a transmit signal and a return signal. The gauge has a DC/DC converter connected to a power supply interface, and configured to convert a first voltage to a second voltage, lower than the first voltage, and an energy storage. The gauge further has a switch, connected between the DC/DC converter and the energy storage, the switch having a non-conducting state for disconnecting the energy storage from the DC/DC converter when the transceiver circuitry is active, and a conducting state for connecting the energy storage to the DC/DC converter only when the transceiver circuitry is inactive.

Abstract: A radar level gauge system controllable between a measurement state and a signal processing state. In the measurement state a first timing signal circuit is enabled, a microwave signal source generates a transmit signal with a time-varying frequency being related to first timing signals from the first timing signal generating circuitry, and a sampler samples a mixer signal at sampling times related to the first timing signals. in the signal processing state, the first timing signal circuit is disabled, and a signal processor determines the filling level based on the sampled values of the mixer signal using second timing signals from a second timing signal generating circuit.

Abstract: A radar level gauge arrangement for determining the fill level of a filling material in a tank is disclosed, which arrangement is mounted on a hatch of a tank and/or on a support which is adapted to be mounted on a hatch of a tank. The arrangement comprises a transmitter for transmitting measuring signals at least along a first axis for determining the fill level of the tank; a receiver for receiving echo signals corresponding to the distance to the surface; a first processing circuitry for receiving the echo signals and to determine a fill level of the tank based on the echo signal; an inclinometer attached to the support and adapted to generate an inclination output corresponding to the inclination relative the surface normal; a second processing circuitry for generating, based on the inclination output, an angular output when there is an angular difference between the first axis and the surface normal.

Abstract: A method for providing narrow-band interference unaffected measurement of a distance to a surface of a product kept in a tank, comprising mixing a return signal with a transmit signal to provide an intermediate frequency signal, and determining the distance, based on the intermediate frequency signal. The step of determining the distance further comprises dividing the intermediate frequency signal into a plurality of frequency portions, wherein each frequency portion corresponds to a frequency interval of the transmit signal, identifying disturbed frequency portions as frequency portions affected by narrow-band interference, and determining the distance based on frequency portions being unaffected by narrow-band interference. By dividing the IF-signal into frequency portions corresponding to frequency intervals of the transmit signal, frequency intervals where narrow-band interferences are present may be detected.

Abstract: A radar level gauge arrangement for determining the fill level of a filling material in a tank is disclosed, which arrangement is mounted on a hatch of a tank and/or on a support which is adapted to be mounted on a hatch of a tank. The arrangement comprises a transmitter for transmitting measuring signals at least along a first axis for determining the fill level of the tank; a receiver for receiving echo signals corresponding to the distance to the surface; a first processing circuitry for receiving the echo signals and to determine a fill level of the tank based on the echo signal; an inclinometer attached to the support and adapted to generate an inclination output corresponding to the inclination relative the surface normal; a second processing circuitry for generating, based on the inclination output, an angular output when there is an angular difference between the first axis and the surface normal.

Abstract: A self-diagnosing FMCW radar level gauge and a method for providing self-diagnosing with a radar level gauge is provided in a radar level gauge comprising a transceiver, a mixer, a signal propagating device and a signal propagation path connecting the transceiver and the signal propagating device, a filter arrangement and processing circuitry. The filter arrangement provides a filtered intermediate frequency signal. The transceiver outputs either a diagnostic sweep configured such that a reference echo from the signal propagation path is detectable in said filtered intermediate frequency signal, or a measurement sweep configured such that the reference echo is suppressed in the filtered intermediate frequency signal and that a surface echo is detectable. The processing circuitry is configured to self-diagnose the radar level gauge based on the reference echo, and to determine the distance to the surface based on the surface echo.

Abstract: The present invention relates to a radar level gauge system comprising a signal propagation device; a microwave signal source; a microwave signal source controller; a mixer configured to combine a transmit signal from the microwave signal source and a reflection signal from the surface to form an intermediate frequency signal; and processing circuitry coupled to the mixer and configured to determine the filling level based on the intermediate frequency signal. The microwave signal source is configured to exhibit a phase noise greater than or equal to ?70 dBc/Hz @ 100 kHz offset from a carrier frequency for the transmit signal.

Abstract: The present invention relates to a radar level gauge system comprising a signal propagation device; a microwave signal source; a microwave signal source controller; a mixer configured to combine a transmit signal from the microwave signal source and a reflection signal from the surface to form an intermediate frequency signal; and processing circuitry coupled to the mixer and configured to determine the filling level based on the intermediate frequency signal.

Abstract: The present invention relates to a radar level gauge system comprising PLL circuitry for generating an output signal. The PLL circuitry is configured to indicate a lock state of the PLL circuitry; and signal modifying circuitry is connected to the PLL circuitry for receiving the output signal and for modifying at least one property of the output signal for forming the transmit signal. The signal modifying circuitry is arranged and configured to receive a PLL status signal indicative of the lock state of the PLL circuitry, and to modify the at least one property of the output signal in response to the PLL status signal indicating that the PLL circuitry is in a locked state.

Abstract: A radar level gauge arrangement for determining the fill level of a filling material in a tank is disclosed, which arrangement is mounted on a hatch of a tank and/or on a support which is adapted to be mounted on a hatch of a tank. The arrangement comprises a transmitter for transmitting measuring signals at least along a first axis for determining the fill level of the tank; a receiver for receiving echo signals corresponding to the distance to the surface; a first processing circuitry for receiving the echo signals and to determine a fill level of the tank based on the echo signal; an inclinometer attached to the support and adapted to generate an inclination output corresponding to the inclination relative the surface normal; a second processing circuitry for generating, based on the inclination output, an angular output when there is an angular difference between the first axis and the surface normal.

Abstract: A self-diagnosing FMCW radar level gauge and a method for providing self-diagnosing with a radar level gauge is provided in a radar level gauge comprising a transceiver, a mixer, a signal propagating device and a signal propagation path connecting the transceiver and the signal propagating device, a filter arrangement and processing circuitry. The filter arrangement provides a filtered intermediate frequency signal. The transceiver outputs either a diagnostic sweep configured such that a reference echo from the signal propagation path is detectable in said filtered intermediate frequency signal, or a measurement sweep configured such that the reference echo is suppressed in the filtered intermediate frequency signal and that a surface echo is detectable. The processing circuitry is configured to self-diagnose the radar level gauge based on the reference echo, and to determine the distance to the surface based on the surface echo.

Abstract: The present invention relates to a radar level gauge system comprising a signal propagation device; a microwave signal source; a microwave signal source controller; a mixer configured to combine a transmit signal from the microwave signal source and a reflection signal from the surface to form an intermediate frequency signal; and processing circuitry coupled to the mixer and configured to determine the filling level based on the intermediate frequency signal. The microwave signal source is configured to exhibit a phase noise greater than or equal to ?70 dBc/Hz @ 100 kHz offset from a carrier frequency for the transmit signal.

Abstract: The present invention relates to a radar level gauge system comprising a signal propagation device; a microwave signal source; a microwave signal source controller; a mixer configured to combine a transmit signal from the microwave signal source and a reflection signal from the surface to form an intermediate frequency signal; and processing circuitry coupled to the mixer and configured to determine the filling level based on the intermediate frequency signal.