Abstract: In a method for the automatic inspection of a welding seam using heat flow thermography, a feature vector is established which represents a time course of a detected heat flow. The feature vector is used to determine, from a series of thermal images, a first characteristic thermal image, which corresponds to a minimum heat flow through an object to be examined, and a second characteristic thermal image, which corresponds to a maximum heat flow through the object, wherein a heat flow directly from an excitation source has already dissipated. A suitable thermal image is used from the series of thermal images to detect and evaluate the welding seam in relation to defects of various defect types, for each defect type, the characteristic thermal images being used as references to determine the respective suitable thermal image.

Abstract: In a method for the automatic inspection of a welding seam using heat flow thermography, a feature vector is established which represents a time course of a detected heat flow. The feature vector is used to determine, from a series of thermal images, a first characteristic thermal image, which corresponds to a minimum heat flow through an object to be examined, and a second characteristic thermal image, which corresponds to a maximum heat flow through the object, wherein a heat flow directly from an excitation source has already dissipated. A suitable thermal image is used from the series of thermal images to detect and evaluate the welding seam in relation to defects of various defect types, for each defect type, the characteristic thermal images being used as references to determine the respective suitable thermal image.

Abstract: Digital signals are commonly transmitted using the single-carrier method or the multicarrier method, for example. Both methods use one carrier frequency per transmission channel or subchannel of predetermined bandwidth. According to the invention, at least two carrier frequencies (f1, f2, f3) are used to increase the transmission capacity of a channel. The distance between two carrier frequencies is less than the absolute value of a carrier frequency (f1, f2, f3) by a factor of, e.g., 500. The beat frequency resulting from the combination (ADD) of several carrier frequencies (f1, f2, f3) in a channel is negligible, particularly if the transmitted carrier frequencies (f1, f2, f3) are in phase at the start of oscillations. By the combination (ADD) of several carrier frequencies (f1, f2, f3), equal resulting carrier frequencies can be obtained for different bit streams (DATA1, DATA2, DATA3).

Abstract: A system for incubating sample liquids is proposed where the incubating vessels are placed into the bores of an incubator block with the aid of a rack. The rack has bores in which the incubating vessels are hanging. The bores of the rack and the ones in the incubator block are adjusted to one another so that the incubating vessels fit into the bores of the incubator block when the rack is placed onto the incubator block.

Abstract: Provision of an area-covering, low-cost infrastructure for a telepoint system. Use of public telepoint base stations (TP) and private base stations (1, 2, 3). Every subscriber can make a call via any private base station or any telepoint base station.

Abstract: A radiotelelphone system in the form of a private branch exchange (12) within and/or outside one or more buildings is equipped with a plurality of mobile subscriber units (28), a plurality of transmitter/receiver units (27) capable of communicating with the subscriber units (28) by radio, and a central unit (26) cooperating with the transmitter/receiver units (27). In order that such a radiotelephone system not only permits mobile telephoning within and/or outside buildings but also can be installed later and adapted to changing requirements in a simple manner, the transmitter/receiver units (27) are arranged and designed to form not only a radio link to at least one of the subscriber units (28) but also, via respective adjacent transmitter/receiver units (27), a radio-link chain (radio bus) to the central unit (26), which has a separate transmitter/receiver unit.

Abstract: In a sensor head (1), hemispherical in form, a plurality of optical fibers (4) is uniformly distributed over the convexly arched surface area (3), and mounted therein. The other ends of the optical fibers (4) are gathered into a bundle (6) whose end face opposes a detector matrix (8) comprising a plurality of detectors. By a subsequently arranged evaluating circuit, and by assigning the detectors to the individual optical fibers (4), there is determined the direction and, by summing up the individual charges of the detectors, there is also recognized the intensity of the incident radiation.Some additional bundles (15) of optical fibers (16) are disposed by being distributed among the optical fibers (4). From each such bundle (15), an equal number of optical fibers (16) is led to each of several detectors (17). These detectors (17) are provided with individual filters (18, 19, 20) or a common filter (23) having certain wavelength responsive regions.

Abstract: This relates to a reference station for distance-measuring systems wherein the distance between aircraft and the reference station can be measured. The station comprises an antenna and at least one receiver and/or transmitter. The antenna consists of a plurality of spatially distributed elements.

Abstract: With the increase in air traffic, it has become increasingly important to transmit more information (e.g. addresses, position data, altitude and angle values) between aircraft and ground. This is done by modulating the phase of the carrier wave of DME or TACAN signals, the phase modulation being so chosen in the invention that the predetermined bandwidth of a DME/TACAN channel is not exceeded as a result of the phase modulation. In this way, full compatibility with existing DME or TACAN systems is achieved.

Abstract: This DME ground station permits the distance from the touchdown point (where no transponder can be installed) to be measured on the aircraft without any change in the airborne equipment. The time difference between the reception of an interrogating signal and the transmission of a reply signal is chosen so that the transmission of reply signals from the DME transponder located on one side of the runway corresponds to a transmission from the touchdown point with respect to the signal transit time.On the ground, a DME transponder is located on one side of the runway on a level with the touchdown point, and a receiver and a direction finder are provided on the other side.

Abstract: A surface based direction finder for determining the direction of radiations from a remote station (aircraft for example), using a plural element linear or circular receiving antenna array. The arriving energy phases are measured in at least one element group with two element pairs, (for example) the elements of each pair being equally spaced and aligned so that a line joining elements of even ordinal number is parallel to the line joining the elements with odd ordinal numbers. The amplitudes (m1, m2, m3 and m4) and the phases (.alpha.1, .alpha.2) of the rf signal picked up by each element are measured separately and the phase .beta. of the desired wave is determined by computer solution of the typical equation derived from the law of consines;m1.sup.2 + m2.sup.2 -2m1 m2 cos (.alpha.1 - .beta.)= m3.sup.2 + m4.sup.2 - 2m3m4 cos (.alpha.2- .beta.).Other configurations employing three elements in line and elements in a circle are also described and the corresponding cosine law equations given.