A pulsed radar level gauge comprising a pulse generator configured to generate a transmit signal (S.sub.T) in the form of a pulse train, a propagation device connected to direct the transmit signal (S.sub.T) into a tank and return a microwave return signal (S.sub.R), a receiver, sampling circuitry configured to provide a time expanded tank signal, and processing circuitry for determining said filling level based on the time expanded tank signal. The gauge further comprises impedance increasing circuitry arranged to ensure that an input impedance of the receiver is at least 2 kΩ and a delay line arranged between said receiver and said propagation device, the delay line configured to introduce a delay greater than said pulse duration, such that said time expanded signal includes a transmitted pulse.

A testing device for testing a distance sensor that operates using electromagnetic waves includes: a receiving element for receiving an electromagnetic free-space wave as a receive signal (S.sub.RX); and a radiating element for radiating an electromagnetic output signal (S.sub.TX). In a test mode, a test signal unit generates a test signal (S.sub.test), and the radiating element is configured to radiate the test signal (S.sub.test) or a test signal (S′.sub.test) derived from the test signal (S.sub.test) as the electromagnetic output signal (S.sub.TX). In the test mode, an analysis unit is configured to analyze the receive signal (S.sub.RX) or the derived receive signal (S′.sub.RX) in terms of its phase angle (Phi) and/or amplitude (A) and store a determined value of phase angle (Phi) and/or amplitude (A) synchronously with the radiation of the test signal (S.sub.test) or of the derived test signal (S′.sub.test) as the electromagnetic output signal (S.sub.TX).

Methods and structures are disclosed for using a graphics processing unit (GPU) to detect and organize pulses in an efficient, parallel manner. A received signal is divided into a plurality of sub-batches. Each of the plurality of sub-batches is processed in parallel by detecting a number of pulses present within each of the plurality of sub-batches. A scanning algorithm process for combining the pulse information of the detected pulses includes providing pulse information from detected pulses within a plurality of subgroups with each subgroup including 2.sup.n sub-batches, with n equal to a number of iterations of performing the providing, and repeating the iterations, increasing n by 1 for each iteration, until 2.sup.n is equal to the total number of sub-batches in the plurality of sub-batches. An output array is generated having a size based on a total combined pulse count and including sequential pulses from the plurality of sub-batches.

An apparatus for radar synchronization may include a local radar device configured to transmit and receive radar signals; a wireless device configured to wirelessly transmit and receive data; at least one processor operably coupled to the wireless device and the radar device, and the at least one processor configured to perform a method including obtaining local radar information regarding one or more radar pulses sent and/or received by the local radar device; and obtaining neighboring radar information associated with radar pulses sent and/or received from one or more neighboring radar devices; and updating a radar data structure using the obtained local and neighboring radar information, wherein the radar data structure comprises radar information for each of a plurality of radar pulses transmitted by the local radar device and/or the one or more neighboring radar devices.

Aspects of the invention provide improvements to analyze data collected by a radar system. One of the systems includes a phased array module configured to transmit a sequence of pulses to an environment according to a pre-determined pattern. A data analysis system constructs an image based on returned signals from a single point received by the phased array module, and determines one or more characteristics of a target object in the environment based on the image constructed from the returned signals from the single point.

A method for controlling a radar apparatus that detects an object using frequency modulation includes: performing first reception of a radio wave in a state where transmission of a radio wave for detecting the object is stopped, to obtain a first reception signal; performing second reception of a radio wave in a state where the transmission of the radio wave is stopped, to obtain a second reception signal, after the performing of the first reception; acquiring a strength of a difference signal between the first reception signal and the second reception signal; comparing the strength with a threshold value; and starting the transmission of the radio wave in a case where the strength is equal to or less than the first threshold value in the comparison.

Example embodiments describe a method for estimating a number of persons present in a room including i) obtaining measurements of electromagnetic sounding signals transmitted within the room; ii) determining at least one reverberation time from the measurements; iii) determining the number of people in the room based on the at least one reverberation time, on a room parameter indicative for a capacity of the room for absorbing the signals and a person parameter indicative for an average capacity of a person for absorbing the signals.

A clutter suppressing device for suppressing echo data of reflection waves caused by radar transmission signals reflecting on a static object is provided. Each of the radar transmission signals is transmitted at a predetermined azimuth from a radar antenna at a predetermined time interval. The clutter suppressing device includes an echo data memory configured to sequentially store a plurality of echo data of reflection waves caused by the radar transmission signals reflecting on objects, a filter configured to select, from the plurality of echo data, a data row in the azimuth direction for a predetermined distance, and suppress, in the data row, echo data of a target object moving at a speed within a predetermined range, and a suppression echo data output unit configured to output suppression echo data containing the echo data suppressed by the filter.

An apparatus for determining the fill level of a fill substance in a container, comprising at least one antenna element. The at least one antenna element has a hollow conductor, wherein there is arranged at a first end region of the hollow conductor a coupling element for the out-coupling of transmission signals and for the in-coupling of received signals, wherein there is arranged at a second end region of the hollow conductor a radiating element directed toward the fill substance, a transmitting/receiving unit having a signal generator for producing the transmission signals. The transmitting/receiving unit determines the fill level of the fill substance in the container based on the travel time of the transmission- and received signals. The connecting line and/or the hollow conductor are/is embodied in such a way that the transmission signals are transmitted time delayed, so that the distance between the at least one antenna element and the surface of the fill substance is virtually increased and the received signal is isolated in time from disturbances of the transmitting/receiving unit, which arise in the case of producing the transmission signals.

Provided are a direct wave suppression method and system for a microwave imaging system. The method includes a series of filtering operations, such as conversion from a frequency domain to a time domain, filtering, conversion from the time domain to the frequency domain, and cancellation subtraction, on an echo signal set composed of echo signals obtained by a vertical linear array antenna at all the equivalent antenna collection positions thereof.