Abstract: The object of the present invention is to provide an active antenna system which is flexibly configurable and efficient in operation. According to a first aspect of the present invention an active antenna system comprises a radio equipment having a plurality of transceiver modules, each transceiver module being connected to at least one antenna, and a radio equipment control unit having a hub being connected to the transceiver modules via an antenna interconnect. The hub is embodied for receiving base band signals via the antenna interconnect from the transceiver modules and to extract channel signals from the received base band signals. As the hub is arranged in the radio equipment control unit which is part of a base station the base band signals are transmitted to the radio equipment control unit without extracting the channel signals. This allows easily to distribute the base band signals on several data connections, particularly several antenna cables, of one antenna interconnect.

Abstract: A mineral-insulated electrical cable has a tubular casing and several metallic conductors running inside the tubular casing and projecting out of it, which are insulated against one another and against the tubular casing. The metal casing has on at least one end a gas-tight seal through which the conductors are passed, and each conductor projecting out of the seal has in connection with the seal and over a part of its length a sheath made of ceramics, glass and/or glass ceramics. In order to improve the resistance of the MI cable to corrosion, each sheath is constructed as a sleeve of the respective conductor with at least one liquid-tight layer in connection with the seal of the tubular casing.

Abstract: A measuring sensor for measuring a fluid includes a longitudinally extending housing having first and second ends and having an inlet opening at the first end for the fluid to be measured, and a sensor chip provided in the housing. The sensor chip has a sensor element provided towards the inlet opening and at least one electrically conducting contact provided towards the second end of the housing. The electrically conducting contact is connected to the exterior by a metal jacket lead having an outer metal tube, at least one internal conductor, and a mineral material for electrically insulating the at least one conductor, the outer metal tubing connected in a fluid-tight manner to the second end of the housing.

Abstract: According to the state of the art, either two separate sensor elements are generally used to determine the exhaust gas temperature and the air/fuel ratio, lambda, or the temperature and lambda readings are not taken simultaneously, at least at temperatures of less than 250.degree. C. In addition, sufficiently precise simultaneous measurement is only possible during stationary operation. The process according to the invention and the corresponding sensor arrangement now make it possible to obtain a precise temperature and lambda reading at a minimal degree of metrological complexity, especially under non-stationary conditions, in that a heated sensor, which exhibits a temperature-sensitive and oxygen-sensitive element on a carrier element, is used to measure the exhaust gas temperature, even at low temperatures with the heating system switched off, while a lambda reading is obtained simultaneously, with the latter being possible only at higher temperature ranges.

Abstract: Measuring sensor to measure a gas, comprising: a housing having an inlet opening for the gas to be measured, a sensor chip located within said housing and having a sensor element at one end area of the sensor chip facing the inlet opening and an electrical connection connected electrically with the sensor element provided at another and, and with at least one contact trace which is electrically conducting, wherein the electrical connection is joined to the contact trace by laser welding.

Abstract: A measuring sensor for measuring a fluid includes a longitudinally extending housing having first and second ends and having an inlet opening at the first end for the fluid to be measured, and a sensor chip provided in the housing. The sensor chip has a sensor element provided towards the inlet opening and at least one electrically conducting contact provided towards the second end of the housing. The electrically conducting contact is connected to the exterior by a metal jacket lead having an outer metal tube, at least one internal conductor, and a mineral material for electrically insulating the at least one conductor, the outer metal tubing connected in a fluid-tight manner to the second end of the housing. In order to secure the sensor to an installation opening, a collar is welded to an outside of the housing at a selected position corresponding to a selected installation depth of the opening of the housing into the measuring opening.

Abstract: A system for monitoring the operatibility of catalytic converters and/or lambda probes in exhaust gas detoxification systems. It is characterised in that a pollutant sensor is placed downstream of (in relation to the exhaust gas stream) or in the catalytic converter, in that the lambda value and/or oxygen content of the exhaust gas are altered by a specific amount either by the engine or by a device, and in that the electrical output signal from the pollutant sensor is compared in a comparator circuit to a value curve stored in a storage unit and corresponding to the defined alteration of the lambda value.

Abstract: An electrode material is provided for electrochemical sensors, particularly for sensors detecting combustible gases. For these types of applications, perovskite electrode materials are known which, however, by modification of their oxygen stoichiometry, have a considerable charge carrier mobility. These defects are the causes for an additional, catalytic activity with oxidation processes at electrodes. The measurement of hydrocarbons from combustible gases is thus distorted with electrode materials of this type. These disadvantages are overcome by making such electrode materials from mixed oxides with non-perovskite crystalline structures, which have chemical compositions of one or more of the following general formulas: (A/D).sub.3-y B.sub.x C.sub.5-x O.sub.12.+-..delta., D.sub.1-y B.sub.1-x C.sub.x O.sub.4.+-..delta., D.sub.2-y B.sub.8-x C.sub.x O.sub.16.+-..delta., D.sub.2-y B.sub.1+x C.sub.1-x O.sub.5.+-..delta., or D.sub.2-y B.sub.x C.sub.2-x O.sub.7.+-..delta.

Abstract: A catalytic converter for cleaning exhaust from combustion processes, especially exhaust from internal combustion engines, and the manufacturing method thereof, the converter including a housing and a plurality of packets provided therein. Each of the packets includes at least one corrugated foil joined at contact areas to at least one flat foil, preferably by soldering or welding. The flat and/or corrugated foil is provided at least partially with a catalytically active coating. The spaces between the corrugated foil and/or between the at least one flat foil and the at least one corrugated foil define channels running parallel to one another through which the combustion gas flows. At least one electrically heatable foil is connected on or in at least one packet with good heat conduction.

Abstract: The invention relates to catalytic converters to be placed in the flowing exhaust of exhaust gas installations, preferably internal combustion engines, with a carrier material provided with a catalyst-containing ceramic coating and at least one temperature sensor applied in thick film technique, which is characterized in that the temperature sensor is located on the surface of the carrier material and that the catalyst-containing ceramic coating covers the temperature sensor.

Abstract: The invention relates to a gas sensor, preferably a lambda probe for determining pollutant and/or oxygen content in the exhaust of internal combustion engines or furnaces, with a metal housing that has mounting means for installing the gas sensor in an exhaust chamber, a ceramic part located inside the metal housing to receive a sensor support with sensor elements, one end of which projects into the exhaust chamber and whose other end is connectable with electrical terminals, characterized in that the ceramic part, in its area away from the exhaust, is secured by a positive connection in at least the radial direction in a metal housing and a sealing element is provided in an area of the ceramic part located downstream from the positive connection, said element being connected firstly with the outside wall of the ceramic part and secondly abutting a wall of the metal housing in a gas-tight manner.

Abstract: A novel apparatus, for determining the concentration of gas components in exhaust gas from a motor vehicle, features a lambda sensor element, an electric heater thermally coupled to the sensor element, a control unit regulating application of voltage to the heater, and at least two voltage sources which can be alternatively applied to the heater, as commanded by the control unit.

Abstract: The invention relates to a combination of a heated lambda sensor with a stepped or binary sensor characteristic and another heated lambda sensor to determine the lambda value in a gas mixture, e.g. in the exhaust gas preferably of internal combustion engines, the output signal from one lambda sensor being used to calibrate the other one, and the two lambda sensors are arranged closely beside each other, the other lambda sensor having a wide-baud sensor characteristic.

Abstract: A housing (5) gas sensors, preferably lambda probes for detecting the content of pollution or oxygen or both in exhaust from, preferably, internal-combustion engines. A protective outer housing has electric connections at one end for a sensor mounted on a metal. A perforated protective cap accommodates the sensor and is intended for exposure to the gas being analyzed at the other end. A ceramic shape accommodates the connections and/or the metal and is accommodated in turn in the outer housing. The ceramic shape consists of at least two halves with a slot that is open along one side at the first end and with contacts resting flat against the base and walls of the slot with one side elevated above the open side. Each half also accommodates a depression extending all the way to the other end with the metal fitting into the depressions. At least the projecting areas of the contacts are in the vicinity of the depression. The connections are on the back of the contacts.

Abstract: There is provided a start-up catalyzer for catalyzing exhaust gas from an internal combustion engine in which flat and corrugated sheets are disposed in alternating relation. Some of the flat sheets have an electrically conductive resistance-heating layer which may be catalytically active and in form of a plurality of rosette-shaped conductive loops connected in series.

Abstract: The invention concerns a device for continuously monitoring the level of at least one gaseous constituent in a mixture of gases. The drawbacks of the known devices are complexity, high power consumption, large size, and, due to their high mass, non-uniform distribution of temperature, entailing imprecise measurement, and inertia, especially at the commencement of operation. These drawbacks are eliminated with a base in the form of a water with at least two electrodes in the form of separated thin coatings and with a temperature sensor separated from the electrodes on one side and with a heater in the form of an electric-resistance heating coating on the other side.

Abstract: The invention concerns a process for manufacturing inert, catalytic or gas-sensitve ceramic layers for gas sensors which comprises coating an uncoated insulative substrate with a layer of paste composed of a powdered semiconductor material of SrTiO.sub.3 and an organic paste material having a thickness of 1 to 100 um and then subjecting the coated substrate to a three phase thermal treatment.

Abstract: Semiconductors for resistive gas sensors or resistive semiconductor gas sensors with high speed of reaction are disclosed. These semiconductors are appropriate to measure the partial pressure of oxygen and reducing gases in any predetermined measurement range between 10.sup.-30 and about 1 bar or in the whole of this measurement range, their resistance changes being caused by a volume effect. In particular, these semiconductors have a layer less than 100 .mu.m thick, predetermined geometric structure and clearly marked marginal zones. A specially doped semiconductor composed of perowskit having the general formula A'.sub.x A.sub.1-x-Z1 B'.sub.y B.sub.1-y-Z2 O.sub.3 is applied on a substrate with a paste of an organic base material by a thick film technique. By adding or removing at least one element or by using two different semiconductors the characteristic curve is clearly traced.