Abstract: A method and a system for calibrating a measuring arrangement on the basis of a 16-term error model determines a matrix (A) with measured scattering parameters (Sm) from different calibration standards (3) and with associated actual scattering parameters (Sa) of the calibration standards (3) and determines linear-in-T system errors (Ti) for the calibration of a network analyzer (1) by solving a linear equation system with the determined matrix (A). To solve the linear equation system, a first and a second linear-in-T system error (k, p) are freely selected in each case. With use of reciprocal calibration standards, the determined linear-in-T system errors are weighted with the freely selected first linear-in-T system error (Ti) or with a correct second linear-in-T system error pkor(k)) dependent upon the first linear-in-T system error (k).

Abstract: A method and a system for calibrating a measuring arrangement on the basis of a 16-term error model determines a matrix (A) with measured scattering parameters (Sm) from different calibration standards (3) and with associated actual scattering parameters (Sa) of the calibration standards (3) and determines linear-in-T system errors ({tilde over (T)}i) for the calibration of a network analyzer (1) by solving a linear equation system with the determined matrix (A). To solve the linear equation system, a first and a second linear-in-T system error (k,p) are freely selected in each case. With use of reciprocal calibration standards, the determined linear-in-T system errors are weighted with the freely selected first linear-in-T system error ({tilde over (T)}i) or with a correct second linear-in-T system error (pkor(k) dependent upon the first linear-in-T system error (k).

Abstract: A reconfigurable bandpass filter including at least a tunable planar combline filter including varactor diodes arranged on a carrier board. For automatic calibration of adjustment of blocking voltage during operation, the reconfigurable bandpass filter includes a filter control offering an external abstracted interface. A memory is connected with the filter control. The memory stores calibration data. For approximating of the best possible filter characteristic, the filter control determines, based on memorized data, the best configuration of tuning voltages. The reconfigurable bandpass filter can be used in the field of secondary radar systems.

Abstract: The invention relates to a method and device for measuring the location of a particle beam (10) present in packets in a linear accelerator comprising a hollow chamber structure (4) in which an electromagnetic wave oscillating at a base frequency (f0) is generated in order to accelerate the particles, wherein an electrical measurement signal (M) generated by the particle beam (10) by means of electromagnetic interaction with the measurement recorder (16) is recorded by at least one measurement recorder (16) disposed in the hollow chamber structure (4), said signal being a function of the distance between the measurement recorder (16) and the particle beam (10). According to the invention, the measurement signal (M) is analyzed in a frequency range different from the base frequency (f0) and higher natural frequencies of the hollow chamber structure (4), comprising a whole multiple of the base frequency (f0).

Abstract: A reconfigurable bandpass filter including at least a tunable planar combline filter including varactor diodes arranged on a carrier board. For automatic calibration of adjustment of blocking voltage during operation, the reconfigurable bandpass filter includes a filter control offering an external abstracted interface. A memory is connected with the filter control. The memory stores calibration data. For approximating of the best possible filter characteristic, the filter control determines, based on memorized data, the best configuration of tuning voltages. The reconfigurable bandpass filter can be used in the field of secondary radar systems.

Abstract: A device and a method for the improved directional estimation and decoding by means of secondary radar signals. The device includes: at least one array of antenna elements; a low noise first amplifier and bandpass filter combination connected to a plug-in connector S of the respective antenna elements; a first linear amplifier being connected at a filter output of said combination for amplifying the band-limited signal; a mixer connected to the first linear amplifier for the frequency conversion into a ZF region; a second linear amplifier and bandpass filter combination connected to the mixer output for amplifying and limiting the bandwidth of the signal in the ZF region; a first analog-to-digital converter connected to the second bandpass filter; a configurable signal processor connected to the first analog-to-digital converter; and a processing unit connected to the configurable signal processors.

Abstract: A magnetically-tunable filter comprising a filter housing with two tunable resonator spheres made of magnetizable material, which are disposed one above the other in two filter arms. At least one filter arm provides a fin line or slot line disposed on a substrate layer and extending in the direction towards an electrical contact, and a common coupling aperture, thereby connecting the two filter arms to one another. In this context, one resonator sphere is positioned within each filter arm on each of the two sides of the coupling aperture.

Abstract: An apparatus and a method for determining a distance (r) to a target object (200) proposes transmitting electromagnetic waves in the form of a transmission signal (120a) by a transmitter (111a), receiving at least one part of said transmission signal (120a) reflected by a the target object (200) in the form of a reception signal (120c, 120d) by receiving device (111b) and evaluating the reception signal (120c, 120d) according a reference signal (1230b) which has a known phase difference with respect to the transmission signal (120a) and a frequency equal to the frequency thereof. The reference (120) and reception (120c, 120d) signal frequencies are reduced in a frequency divider (113) with the same predefined divider factor (x) while preserving the existing phase difference between the reference signal (120b) and the reception (120c, 120d) signal in such a way that a reduced frequency reception signal (120b?) and a reduced frequency reception signal (120d) are obtained.

Abstract: The invention relates to a magnetically tunable filter having a filter housing and having two tunable resonator spheres which comprise magnetizable material and are arranged next to one another in two filter branches. Each filter branch comprises a coplanar line arranged on a substrate layer and extending in the direction of an electrical connection, as well as a common coupling opening so that the two filter branches are connected to one another. A resonator sphere is respectively positioned on each side of the coupling opening inside the two filter branches.

Abstract: 1. A device and a method for the improved directional estimation and decoding by means of secondary radar signals. 2.1 Radio-based positioning systems on the basis of secondary radar signals are known. For this purpose special receiver systems are utilized for estimating the direction, and special receiver systems are utilized for decoding secondary radar signals. In particular, a secondary radar system is absent, which, among others, takes into consideration any shortcomings of the hardware used, such as coupled antenna elements, different low-end impedances, deviating distances between the antenna elements, manufacturing and installation tolerances, and the like. 2.

Abstract: In order to image test objects by electromagnetic waves, in particular millimetric waves, a test object is illuminated with the electromagnetic waves, the scattered waves are received, and are evaluated for a representation of the test object in the form of an image based on the principle of “synthetic aperture radar” (SAR). In order to allow as large an area as possible to be imaged with high resolution in a short time, the phase centres of the transmitting and receiving antennas are, according to the invention, moved on a circular path parallel to the respective digital focus planes of the imaging system, and are at the same time shifted linearly in a further direction parallel to the respective focus plane. The method can be used for monitoring people for suspicious objects, for example for monitoring airline passengers at an airport.

Abstract: The invention relates to a method for determining a distance (r) to a target object (200) consisting in transmitting electromagnetic waves in the form of a transmission signal (120a) by a transmitter (111a), receiving at least one part of said transmission signal (120a) reflected by a the target object (200) in the form of a reception signal (120c, 120d) by receiving device (111b) and evaluating the reception signal (120c, 120d) according a reference signal (1230b) which has a known phase difference with respect to the transmission signal (120a) and a frequency equal to the frequency thereof. The reference (120) and reception (120c, 120d) signal frequencies are reduced in a frequency divider (113) with the same predefined divider factor (x) while preserving the existing phase difference between the reference signal (120b) and the reception (120c, 120d) signal in such a way that a reduced frequency reception signal (120b?) and a reduced frequency reception signal (120d) are obtained.

Abstract: A magnetic resonance system has a basic magnet that generates a static basic magnetic field in an examination volume, and a whole-body antenna that emits a homogeneous radio-frequency field in the examination volume, the homogeneous radio-frequency field exhibiting an excitation frequency so that nuclei in an examination subject in the examination volume are excited to emit magnetic resonance signals, and a radio-frequency shield. The radio-frequency shield is arranged between the whole-body antenna and the basic magnet. The whole-body antenna is arranged between the radio-frequency shield and the examination volume. The radio-frequency shield is fashioned to exhibit a high shielding effect in a shielding frequency range that encompasses the excitation frequency. The shielding effect drops to a significantly lower shielding effect on both sides at side bands adjoining the shielding frequency range.

Abstract: A method for imaging test objects by means of electromagnetic waves, in particular for the purpose of checking individuals for suspicious articles, in which method the test object is illuminated by electromagnetic waves, the scattered waves are received and evaluated for an imaginal representation of the test object on the basis of the synthetic aperture principle (SAR). A synthetic aperture is produced by the waves output by an antenna being concentrated initially in spatial terms, the point of high concentration being moved on a reflector along a circle.

Abstract: A magnetically-tunable filter comprising a filter housing with two tunable resonator spheres made of magnetizable material, which are disposed one above the other in two filter arms. At least one filter arm provides a fin line or slot line disposed on a substrate layer and extending in the direction towards an electrical contact, and a common coupling aperture, thereby connecting the two filter arms to one another. In this context, one resonator sphere is positioned within each filter arm on each of the two sides of the coupling aperture.

Abstract: In order to image test objects by electromagnetic waves, in particular millimetric waves, a test object is illuminated with the electromagnetic waves, the scattered waves are received, and are evaluated for a representation of the test object in the form of an image based on the principle of “synthetic aperture radar” (SAR). In order to allow as large an area as possible to be imaged with high resolution in a short time, the phase centres of the transmitting and receiving antennas are, according to the invention, moved on a circular path parallel to the respective digital focus planes of the imaging system, and are at the same time shifted linearly in a further direction parallel to the respective focus plane. The method can be used for monitoring people for suspicious objects, for example for monitoring airline passengers at an airport.

Abstract: The invention relates to a magnetically tunable filter having a filter housing and having two tunable resonator spheres which comprise magnetizable material and are arranged next to one another in two filter branches. Each filter branch comprises a coplanar line arranged on a substrate layer and extending in the direction of an electrical connection, as well as a common coupling opening so that the two filter branches are connected to one another. A resonator sphere is respectively positioned on each side of the coupling opening inside the two filter branches.

Abstract: A magnetic resonance system has a basic magnet that generates a static basic magnetic field in an examination volume, and a whole-body antenna that emits a homogeneous radio-frequency field in the examination volume, the homogeneous radio-frequency field exhibiting an excitation frequency so that nuclei in an examination subject in the examination volume are excited to emit magnetic resonance signals, and a radio-frequency shield. The radio-frequency shield is arranged between the whole-body antenna and the basic magnet. The whole-body antenna is arranged between the radio-frequency shield and the examination volume. The radio-frequency shield is fashioned to exhibit a high shielding effect in a shielding frequency range that encompasses the excitation frequency. The shielding effect drops to a significantly lower shielding effect on both sides at side bands adjoining the shielding frequency range.