Abstract: A transition detection device, generating a variable-duration pulse, such as an enable signal for the input circuits of a CMOS static memory circuit, receiving an input signal that includes a delay circuit of determined delay value, making it possible to generate a delayed enable signal, with a safety margin of duration equal to the delay value. A calibration circuit is provided, which includes an exclusive-OR circuit receiving the input signal on a first input. A controlled delay circuit is provided to deliver an input signal delayed by a second delay value to a second input of the exclusive-OR circuit, which, upon access by the CEB signal, delivers a calibrated output pulse of duration equal to the second delay value, and truncated pulses for any transition occurring on the other inputs of the circuit, in the presence of address transitions or of other, not strictly simultaneous, inputs.

Abstract: A comparator of phase between a digital signal and a clock signal adapted for the construction of a phase locked loop in integrated circuit form, that includes a first channel formed by a flip-flop and an exclusive OR gate, and a second channel formed by a second exclusive OR gate and a delay circuit whose delay is set to half the period of the clock signal. The first channel receives the digital signal and the clock signal and delivers a first detection signal of transition of the digital signal. The second channel receives only the digital signal and delivers a second detection signal of transition of the digital signal.

Abstract: The device can be used on an aircraft or spacecraft. It comprises a laser for emitting short light pulses, a channel for receiving the backscattered light flux and an optical conical scanner means making it possible to orient a direction common to laser emission and to reception via the channel along successive generatrices of a cone. The scanner has a mirror rotated about a scanning axis for deflecting an optical path common to a receiving detector and to the laser along successive directions distributed at regular angular intervals around the scanning axis and several stationary reflectors distributed at the regular intervals. The reflectors are successively inserted on the common optical path by the rotating mirror. The stationary reflectors correspond to different probing orientations along the cone. The rotating mirror has a size very much less than that of the beam entering and exiting the device.

Abstract: The terrestrial sensor device is suitable for use on a satellite or spacecraft. It has a lens for forming an image of the Earth in a focal plane, and a sensor placed in the focal plane. The sensor is constituted by a two-dimensional array of pyroelectric detectors. The device also includes an actuator for oscillating the array in the focal plane, orthogonally to the optical axis of the image-formation lens, at a determined frequency and with an amplitude at least equal to the distribution spacing of the detectors and a processing circuit for acquisition of the output signals of the detectors at the oscillation frequency and for comparison of the output signals with a threshold.

Abstract: A reflector antenna assembly for dual linear polarization includes at least two feeds and two reflectors. At least one reflector has a surface which is nominally electrically transparent to linearly polarized radiation in one direction and is located in front of the other reflector so as to be closer to said feeds. At least one of the reflectors is profiled in a manner such as to enable it to generate at least one complex contoured beam while using one of said feeds.

Abstract: The wheel set comprises a pair of load-carrying wheels that run on a track, and that are steerable about parallel axes on a fixed portion, together with two pairs of guide wheels for bearing laterally against the track. The pairs of guide wheels are situated on either side of the load-carrying wheels, and they are carried by the same guide frame which is displaceable relative to the fixed portion only in rotation about a vertical axis. The guide frame is connected to the load-carrying wheels by a forced steering linkage for the load-carrying wheels. The fixed portion is constituted by a transverse box girder placed above the guide frame and provided with steering pivots for the load-carrying wheels, which pivots are placed beneath suspension cushions for the vehicle.

Abstract: The multi-chip module comprises a co-fired substrate, and, on at least ont face of the substrate, a set of superimposed ceramic insulating layers, fired at a temperature substantially smaller than the firing temperature of the substrate. Conducting interconnection lines are formed in thick layers deposited between said ceramic insulating layers. Electronic components are mounted at the surface of the set of ceramic layers.

Abstract: The luggage rack, which can be used on the roof of a motor vehicle, comprises two rails fixed flat to the roof and at least two crossmembers, the ends of which can slide on the rails and be locked thereto. The two crossmembers include faces opposite each other which can be applied directly against one another so as to constitute a wing.

Abstract: A base station constructs CDMA channels, each defined by a respective spreading sequence which modulates information bits to be transmitted for forming a respective channel signal. The different channel signals are combined, and then modulated on a carrier frequency, so as to produce a phase shift keyed radio signal which is transmitted towards mobile stations. Each spreading sequence has only one real component. For producing the radio signal, a relative phase shift is applied between different channel signals.

Abstract: A synchronization method includes selecting, at a mobile station, at least one periodic pseudorandom sequence (PN) which corresponds to, and is synchronized with, the reference sequence transmitted by a base station on a pilot channel, and received by the mobile station over a propagation path, this operation being carried out regardless of the frequency deviation between the transmitter and the receiver. Various possible sequences are tested by calculating the quantities E[s(t).multidot.s*(t-.tau.)] and E[s(t).multidot.s*(t)], where E[.multidot.] designates the mean value calculated over a predetermined integration time, .tau. designates a predetermined delay, and s(t)=r(t).multidot.c(t) designates the product of the received base band signal r(t) and the value (c(t)) of the tested sequence, and by calculating the ratio .vertline.E[s(t).multidot.s*(t-.tau.)][.vertline./Es(t).multidot.s*(t)]. The sequence under test is selected if the ratio exceeds a predetermined threshold.

Abstract: A digitally controlled beam former for a spacecraft which includes means for periodically calibrating the feed paths of the spacecraft's antenna array by measuring the apparent movement of the center of a reference signal and a nominal signal and utilising the measured data to compensate for at least the phase drift in the antenna feed paths. The measured data may also be used to compensate for amplitude and phase drift in the antenna feed paths.

Abstract: An output circuit for a TTL-CMOS integrated circuit that comprises an output stage with two P MOS and N MOS transistors in parallel, which are connected in cascade with an N MOS enabling transistor between the power supply and the reference voltages. The output stage connected by means of a validation signal TRISB and of P and N MOS transistors delivers an output signal representing the input logic variable to the common point between the P MOS transistor and enabling transistor. A first circuit allows switching of the P MOS transistor by an intermediate switching control signal TRISP and a third circuit allows switching of the N MOS transistor, the circuit operating in mode of feedback of the switching control of the P MOS transistor, the controls being applied successively in order to generate an intermediate switching level belonging to the high logic level.

Abstract: For measuring an amount of relative movement between two elements, such as a vehicle and a track, which are mutually movable, two successive pulses of coherent light are directed from the vehicle to the track under a same incidence angle. From a same location of the vehicle, two images of the interference patterns due to the short pulses are formed. The two pulses are offset from each other in the direction of movement by a distance d approximately corresponding to the amount of relative movement between the two pulses. The actual amount of movement is computed as being the movement which provides the best coincidence between the two images. The comparison can be made by cross-correlation.

Abstract: The safety control device with digital input and analog output, is intended to deliver a mean output power above a specified threshold when two binary input sequences which are complementary or in phase opposition are applied to the input and an output power appreciably below the threshold in all other cases. It comprises a primary voltage source (18) supplying a cascade of several modules (16.sub.1 , . . . , 16.sub.k) each having an AC converter bridge and a rectifier, each branch of the AC converter bridge being controlled by one of the sequences.

Abstract: The method is used to transmit digital signals by radio over a predefined frequency band between a base station and mobile stations. At least one repeater station is used to receive radio signals transmitted by the base station and to retransmit radio signals to the mobile stations over the same frequency band. The spectrum of the radio signals transmitted by the base station to the repeater station is reversed relative to the spectrum of the radio signals retransmitted by the repeater station to the mobile stations. The invention is particularly applicable to radiotelephone communications networks.

Abstract: The cooling device for cooling a travelling-wave tube is deigned to be mounted on board a geostationary telecommunications satellite. The collector of the tube is thermally insulated from the remainder of the tube and it is thermally connected to a radiator by means of a link part passing through a north or a south panel of the satellite structure and insulated from the panel.

Abstract: A dielectric resonator demultiplexer including at least one dielectric resonator filter including a plurality of cascaded dielectric resonators; and a support member on a surface of which the said at least one filter is vertically mounted with the longitudinal axis thereof substantially vertical to the mounting surface.

Abstract: A pluggable electrical connection device comprises at least one pin-shaped male element of electrically conductive material and at least one female element. The female element is a metal coil spring having at least four turns sufficiently spaced apart to receive the male element between two mutually adjacent turns. The coil spring may have end portions which are bent to constitute tabs parallel to an axis of said coil spring and soldered to said support. It may also be locked between two elongated holes formed in two opposed sides of a cage and connected to a base circuit fast with said cage by pin.

Abstract: A memory component has a rectangular semiconductor substrate containing active memory circuits and output terminals on a major surface thereof. An insulating layer on the major surface receives a plurality of metal connection leads, connecting the output terminals to connection pads located on the major surface along only one of longer sides of the substrate. A plurality of additional pads are distributed between the connecting pads and are devoid of connection leads. A memory module comprising several stacked memory components is also described, which uses the additional pads as relays.