Radar cross-section (RCS) images are valuable for understanding the 3-D target scattering center distribution of objects. However, RCS imaging requires more complex measurement systems and much data points compared to conventional 2-D methods. A reduction effort can be achieved by using a tomographic technique based on amplitude-phase-spectrum estimation, scale-invariant feature transform image registration, constant false alarm rate detection. Besides an amplitude spectrum, proposed method...

Spherical near-field measurements are regarded as the most accurate technique for characterization of an Antenna Under Test's (AUT) radiation. The AUT's far-field radiation characteristics can be calculated from Mode Coefficients (SMC), or spherical wave coefficients, determined data. At Terahertz frequencies, approximation distance classically defined by Fraunhofer is easily met. Still, framework also applied to beyond near field, providing a reliable way determining its pattern with any...

One of the main advantages a robot-based antenna measurement systems compared to traditional positioning like roll-over azimuth positioners are additional degrees freedom and, thus, increased flexibility with respect sampling grid and placement under test (AUT). However, this also requires precise alignment probe AUT obtain accurate results. In paper, an electrical technique based on six term error model is introduced. The misalignment errors estimated from single <tex...

Robot-based measurement systems provide new degrees of flexibility in antenna technology. However, order to exploit the potential these systems, they should not be used analogously conventional positioning such as linear axes or roll-over-azimuth positioners. Spline-based paths are one way exploiting potentials and, addition almost arbitrary paths, also allow more precise trigger signals at desired sampling points. Furthermore, grids exist which require significantly fewer points for a...

The robot-based antenna measurement system at the Institute of High Frequency Technology RWTH Aachen University is put into operation and its measuring capability proven by preliminary spherical data. For this purpose, near- far-field data a standard gain horn are shown compared with institute's compact test range. influence scalar feed used as probe compensated full high-order correction. It that deviation in E-plane mainly ≲ -40 dB wide parts angular range radiation pattern. In view fact...

highly integrated systems like modern automotive radars cannot be measured with a conventional antenna measurement system, as there is no access to the feed line. The possibility of measuring two-way pattern against reflector using transmit and receive module radar device itself already partially used. However, studies on accuracy for this setup are still missing. Within study, active radiation measurements done within robot-based system Institute High Frequency Technology (IHF) RWTH Aachen...

Three-dimensional radar cross-section (RCS) images are a valuable support for understanding the scattering events occurring at target. Traditional RCS measurement methods require large angular range and many points to provide sufficient resolution unambiguousness. This paper proposes usage of high-resolution techniques, enabled by taking only polarimetric signal components into account. Therefore, geometry compact antenna test is integrated model similar one direction arrival (DOA) problem....

A maximum determinant sampling grid (MDSG) presents a fully non-redundant for spherical near-field antenna measurements which can be efficiently measured using robot-based measurement systems. Although the position of points is determined by grid, sequence data acquisition still optimized to reduce time. new trajectory optimization approach proposed reduces sharp curves in path at cost longer total length. It shown that this significantly increases average speed and time compared an shortest...

Robot-based measurement systems typically have a larger tolerance with respect to their positioning accuracy than conventional systems, e.g. roll-over-azimuth positioners. However, for spherical near-field measurements, the of probe is an important uncertainty in required near-field-to-far-field transformation. One way account those non-idealities use higher-order pointwise correction (PPC). It allows consider actual position and orientation by additional rotations translations receive...

Spline-based motion sequences, in contrast to canonical path definitions such as circular or linear paths, represent the optimal mode of operation for robot-based measurement setups. By specifying not a trajectory but set required sampling points, robot controller is granted additional degrees freedom optimize speed smoothness motion. A comparison identical spherical near-field measurements based on canonically defined trajectories splines yields that latter enables increase average and,...

This paper presents a detailed investigation of the scattering mechanisms occurring at different traffic signs and guide post in 77 GHz automotive radar frequency band. By utilizing polarimetric ISAR imaging process, centers are spatially resolved 2D image plane. The proposed phase drift compensation approach provides basis for valid analysis scatterers. A potential vehicle self-localization relying on such landmarks will benefit from this knowledge.

Radar sensors are an essential component in the automotive sector and take over safety-relevant functions field of autonomous driving. Therefore, need for validation radar systems is increasing. Within this paper, a measurement setup automated static dynamic tests integrated set up robot-based chamber available at Institute High Frequency Technology, RWTH Aachen University. The system parameters two-way pattern, range speed resolution as well angular separation capability measured analyzed...

Height estimation of radar targets is particular importance for self-localization and autonomous driving. It an essential part the risk assessment makes it possible to assess whether certain obstacles can be traversed or evasive maneuver must initiated. In order evaluate such situations as reliably possible, high demands are placed on classification targets. New possibilities opened up by determining not only total height, but intensity distribution resolved height. To prove advantages,...

An antenna measurement system at the Institute of High Frequency Technology RWTH Aachen University is being established containing a six-axis robot arm allowing realization numerous geometries. Room scattering one most crucial uncertainty terms in every which becomes even more interesting dynamic situation. To determine scattering-induced interference caused by robot, motion-capable model developed and firstly simulated using multi-level fast multipole method between 8 GHz 12 to...