A method for encoding and storing digital data, which include a plurality of real values, in a signal processing unit of a radar sensor. In the method, at least one real value r in an exponential representation in the form r=m.Math.b.sup.−k is stored, where m is a digital mantissa having a length p, b is a base, and k is a positive number that is encoded as a digital number having a length q. The values r for the compressed storage are transformed into an exponential representation in the form r=m*.Math.b.sup.−f(k), where m* is the mantissa and f is a function of k that is selected from multiple functions, and the selection of function f takes place based on a value distribution of the values to be stored.

A phased-array antenna device with a long operating life without mechanical parts, has a high spatial resolution, and realizes microwave observation of broadband and highfrequency resolution. The phased-array antenna device performs direct A/D conversion through a BPF on an antenna analog signal amplified by an amplifier. Then, the device performs a second cross-spectrum calculation after conversion into complex frequency data through FFT. To detect a weak electromagnetic wave, the device repeatedly performs a second FFT over a long period and lastly performs integration.

A method (1) for passively locating a radio emission source (2a, 2b) is described. The method includes including receiving radio signal datasets (D) corresponding to each of three of more sensors (3). Each sensor (3) includes at least one radio receiver (4). The method also includes receiving or retrieving a physical location corresponding to each sensor (3). The physical locations define a convex hull (5). The method also includes determining whether an emitter signal (8) within a target frequency range is present in any of the radio signal datasets (D), and assigning any radio signal dataset which comprises the emitter signal as a detection dataset. The method also includes, in response to determining three or more detection datasets, calculating a signal location (r) based on arrival times of the emitter signal and the respective physical locations. The method also includes generating a locus of possible positions based on calculating two or more alternative signal locations. Each alternative signal location is calculated by adding synthetic noise to one or more of the detection datasets and repeating the calculations used to calculate the signal location. When the signal location is inside the convex hull, cluster filtering based on circles or spheres is applied. When the signal location is outside the convex hull, cluster filtering is based on ellipses or ellipsoids and on the locus of possible positions. The method also includes outputting one or more estimated radio emission source locations. Each estimated radio emission source location is determined based on a respective cluster of signal locations.

Methods and apparatus for a phase array radar to generate fan beams with curve of constant phase with spoiling in u and/or v space. In embodiments, beam pattern weighting is phase-only and applicable to transmit and receive. In embodiments, the beam pattern accounts for the apparent curvature of the horizon in uv space.

A system for virtual aperture array radar tracking includes a transmitter that transmits first and second probe signals; a receiver array including a first plurality of radar elements positioned along a first radar axis; and a signal processor that calculates a target range from first and second reflected probe signals, corresponds signal instances of the first reflected probe signal to physical receiver elements of the radar array, corresponds signal instances of the second reflected probe signal to virtual elements of the radar array, calculates a first target angle between a first reference vector and a first projected target vector from the first reflected probe signal, and calculates a position of the tracking target relative to the radar array from the target range and first target angle.

An antenna arrangement suitable for a vehicle radar transceiver. The antenna arrangement includes a radiating layer having a surface, the surface delimited by a surface boundary. One or more apertures are arranged on the surface. The antenna arrangement further includes one or more surface current suppressing members arranged on the surface. The one or more surface current suppressing members are arranged to suppress a surface current from an aperture to the surface boundary. The one or more surface current suppressing members include one or more grooves.

A radar signal transmitting method, a radar signal receiving method, and an apparatus are applied to a radar apparatus. The radar signal transmitting method includes: sending a first signal and a second signal in S slots, where a phase of the first signal remains unchanged in the S slots, and the first signal may be equivalent to a SIMO signal; and sending the second signal in at least one of a time division manner or a code division manner, where phase modulation is performed, by using a step of 2πk.sub.y/P, on a signal that is in the second signal and that is sent through each of m transmit antennas, and the second signal is equivalent to a MIMO signal. When P=2, the MIMO signal is sent in a time division manner. When P>2, the MIMO signal is sent in a time division manner and a code division manner.

Example radar systems are presented herein. A radar system may include radiating elements configured to radiate electromagnetic energy and arranged symmetrically in a linear array. The radiating elements comprise a set of radiating doublets and a set of radiating singlets. The radar system also includes a waveguide configured to guide electromagnetic energy between each of the plurality of radiating elements and a waveguide feed. The waveguide feed is coupled to the second side of the waveguide at a center location between a first half of the plurality of radiating elements and a second half of the plurality of radiating elements. The waveguide feed is configured to transfer electromagnetic energy between the waveguide and a component external to the waveguides. The radar system may also include a power dividing network defined by the waveguide and configured to divide the electromagnetic energy transferred by the waveguide feed based on a taper profile.

A system is provided comprising: a plurality of receivers; a plurality of antennas; a calibration device coupled to the plurality of receivers; a plurality of antenna paths, each of the antenna paths being arranged to couple a respective one of the plurality of receivers with a respective one of the plurality of antennas; a plurality of first calibration paths, each of the first calibration paths being arranged to couple the calibration device to different respective first pair of the antenna paths; a plurality of second calibration paths, each of the second calibration paths being arranged to couple the calibration device to a different respective second pair of the antenna paths, each second pair of the antenna paths including at least one antenna path in common with any of the first pairs of the antenna paths.

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.