Rosemount Tank Radar Ab

Saab Ab

Saab Rosemount Tank Radar Ab

Saab Marine Electronics Ab

Valter Nilsson

Fabian Wenger

Niklas Penndal

Anders Jirskog

Anders Höök

Theodor Hassiakis

Max Wallen

Bruno Lumetzberger

P&auml;r Abrahamsson

Ola Bååth

Anders Hoeoek

Niklas Janehag

Max Wallén

The invention relates to a method and a system for providing current from a DC power supply to pulsed loads in an array. The array comprises at least two electronic units. Each electronic unit comprises a regulator connected to an energy storage, to a pulsed load and to a charge control unit. The charge control unit is arranged to control the supply of DC current to the pulsed load connected to the electronic unit. The method comprises: selecting a pulse load pattern for the pulsed loads, selecting a charge control sequence by a control system connected to the electronic units and the DC power supply, starting the selected charge control sequence, starting the pulse load pattern, providing DC current from the DC power supply to each electronic unit at different times according to the selected charge control sequence set by the charge control unit.

Method and system for DC voltage supply of pulsating loads

The present invention relates to a radar system for a vehicle, a method for controlling a radar system, a computer program product, and a vehicle comprising such a radar system. The radar system comprises an antenna arrangement for transmitting and/or receiving electromagnetic waves, a power supply connected to the antenna arrangement, the power supply being arranged to supply the antenna arrangement with operating power. The radar system further comprises an antenna controller connected to the antenna arrangement, the antenna controller being configured to control an operation of the antenna arrangement. The radar system also comprises an auxiliary power source connectable to the antenna arrangement for supplying the antenna arrangement with supplementary operating power so to increase an output power of the antenna arrangement, and a boost controller connected to the auxiliary power source and to the antenna controller, the boost controller being configured to connect and disconnect the auxiliary power source to/from the antenna arrangement. Hereby presenting a radar system capable of increasing the maximum range of the antenna arrangement during an arbitrary period of time without suffering from too heavy penalties in terms of increased weight or cost.

Vehicle radar system comprising an auxiliary power source

A switching mode DC/DC power converter for delivering a direct current to a pulse radar unit. A first switching element connects and disconnects the power converter from a power source in each cycle of the power converter. An inductor charges and discharges in each cycle. A capacitor maintains a DC output voltage as the inductor charges and discharges in each cycle. A second switching element transfers energy from the inductor to the capacitor when the first switch disconnects the switching mode power converter from the power source. A control loop regulates the voltage with a time constant, to a predetermined value by controlling the first switching element. An on time for the first switching element in each cycle is chosen to allow the current through the inductor to fall to zero in each cycle. The cycle is shorter than RF pulse duration and time constant of the control loop is longer than the RF pulses.

Switching mode DC/DC power converter for delivering a direct current to a pulse radar unit

Method for determining product surface distance in a tank comprising:

Radar level gauging

A device for using electromagnetic pulses to determine a distance to a surface includes a pulse generator, a real time sampler and a calibration unit having a signal generator for generating a calibration signal with a predefined frequency. In a calibration mode the real time sampler receives the calibration signal, and an average sample time delay of the sampler is determined based on the sampled calibration signal and the known calibration frequency. In a measurement mode, the real time sampler receives a reflection signal and the distance is determined based on a sampled reflection signal and the average sample time delay. Knowledge of the average delay of the sampler makes it possible to exactly determine the distance (in time and thus space) between two points in the sampled signal.

Calibration of a distance measuring device

A loop-powered field device for determining a process variable and providing a measurement signal indicative of the process variable to a remote location via a two-wire current loop, the loop-powered field device comprising: a measurement device for determining the process variable; and loop interface circuitry for providing the measurement signal to the two-wire current loop and for providing power from the two-wire current loop to the measurement device. The loop interface circuitry comprises: current control circuitry connected to the two-wire current loop and the measurement device, the current control circuitry being controllable by the measurement device to provide the measurement signal to the two-wire current loop; a first converter having inputs connected to the two-wire current loop in series with the current control circuitry, and an output for providing power to the measurement device; and voltage regulation circuitry for regulating a voltage across the current control circuitry towards a desired voltage, by controlling an input voltage across the inputs of the first converter.

Loop-powered field device

A method for determining a process variable of a product in a tank based on a time delay of electromagnetic waves. The method further comprises forming a measurement signal comprising a sequence of values, each value representing a time correlation between a pulse of a reference signal and a reflected signal, sampling and digitizing this measurement signal to form a digital signal, identifying a time window of the digital signal including the surface echo peak, determining a relative time period between a reference time corresponding to the predefined reference and a beginning of the time window, time-to-frequency transforming the digital signal in the time window to obtain a phase spectrum, determining a relative phase shift of the spectrum and using the relative phase shift to calculate a corresponding time shift, and determining the time delay by adding the relative time period and the time shift. The invention is based on the realization that major improvement of measurement performance, compared to amplitude detection only, can be achieved by discrimination of the phase difference between the reflected signal and a reference. The detection is further independent of the pulse waveform and modulation, significantly reducing the requirements on pulse modulation.

Pulsed radar level gauging with relative phase detection

A radar level gauge (RLG) system and method for determining a filling level of a filling material in a tank is disclosed. The RLG system comprises a transmitter for generating and transmitting an electromagnetic transmitter pulse signal, a transmitter controller for controlling means for pulse width adjustment for adjusting the pulse width of the transmitter pulse signal in dependence of at least one application specific condition. Further, the system comprises a signal medium interface connectable to means for directing said transmitter pulse signal towards said filling material and for receiving a reception pulse signal reflected back from said filling material; a receiver for receiving said reception pulse signal from the tank; and processing circuitry for determining the filling level of the tank based on said reflection pulse signal received by said receiver. The application specific condition(s) is e.g. one or several of tank height, level of the filling material, type of filling material, presence of other tank structure providing reflecting surfaces and required accuracy of measurement.

Radar level gauge with variable pulse parameters

A radar level gauge (RLG) using electromagnetic waves for determining a process variable of a product in a tank is provided which includes timing circuitry adapted to provide timing control of a transceiver, and a communication interface arranged to receive power in an intrinsically safe manner and to connect the radar level gauge externally thereof. The RLG further comprises an isolation interface arranged to galvanically isolate the transceiver from the timing circuitry and the communication interface, the isolation interface being arranged to transfer power and timing control from the timing circuitry and the communication interface to the transceiver circuitry.

Radar level gauge with a galvanically isolated interface

A radar level gauge system is disclosed, comprising: a transmitter for transmitting pulsed measuring signals into a tank; a receiver for receiving echo signals from the tank; and processing circuitry for processing the received echo signals, said processing means including an amplifier for amplification of the received echo signals. Further, the amplifier is operable in a high and a low amplification mode, and the processing circuitry is arranged to control the amplifier intermittently in order to be in the high amplification mode only during certain time slots. By intermittently operating the amplifier in a low amplification mode, providing only a low or moderate amplification, or preferably being shut off (i.e. with essentially no amplification), the power required for the amplification could be significantly reduced. Further, the noise generated by the amplifier could be significantly reduced. A corresponding processing circuitry and operating method are also disclosed.

Radar level gauge system with intermittent amplification

A radar level gauge using microwaves coupable to a two-wire process control loop for measuring level of a product in a tank. A microwave antenna unit is directable into the tank. A low power microwave source sends a microwave signal through the antenna unit into the tank. A low power microwave receiver receives a reflected microwave signal from a surface of the product in the tank. Measurement circuitry coupled to the source and receiver initiates transmission of the microwave signal and for determining product level based upon the received signal. Output circuitry coupled to the two-wire process control loop transmits information related to product level over the loop. Power supply circuitry coupled to the two-wire process control loop receives power from the loop being the sole source of power for the low power microwave source, the low power microwave receiver, the measurement circuitry and the output circuitry in the radar level gauge. An isolation circuit non-conductively transfers power from the loop to the power supply circuitry and non-conductively transmits the information between the output circuitry and the loop.

Isolation circuit

A radar level gauge for measuring a level of a surface of a product in a tank having a two-wire process control loop, output circuitry coupled to the two-wire process control loop for setting in the loop a desired value of a loop current (I ) corresponding to the product level, a power supply circuitry coupled to the two-wire process control loop for receiving power from the loop and being a source of power for a microwave source, a microwave receiver, a measurement circuitry and the output circuitry and including a converter for transferring power from the loop to said power supply circuitry by means of feeding a first current (I ) from the loop to the power supply circuitry, a current generator included in said output circuitry for generating in parallel to said first current a second current (I ) in the loop for maintaining said loop current at a value corresponding to said product level and a sensing circuit for determining the value of said second current and having an output indicative of the value of said second current.

Growing community of inventors

Hovås, Sweden

Valter Nilsson