Abstract: The duct element intended to accommodate, on its internal wall (14), a sheathed electrical or optical cable (4) in order to protect it has its internal wall (14) and external wall (13) electrically connected in order thereby to make an element for checking the integrity of the sheath (6) of the cable (4); preferably, it is made of a conductive material.

Abstract: An electrical coupling part comprising a conductive coupling member, an inner conductive layer surrounding the coupling member, an insulating layer surrounding the conductive layer, and an elastic protective sleeve which comprises at least one cylindrical portion adjacent to an end of the insulating layer and a conical portion adjacent to the cylindrical portion, the protective sleeve further comprising, at an end remote from the cylindrical portion, an orifice of greater diameter than the cylindrical portion.

Abstract: The cable includes optical fibers (1) enclosed in an outer sheath (2) having elongate reinforcing members (4) embedded therein, disposed in two diametrically opposite groups (3) each comprising a plurality of mutually tangential reinforcing members (4).

Abstract: The telecommunications cable of the invention comprises optical fibers and stabilization fibers disposed in an envelope in such a manner as to ensure longitudinal coupling therewith, such that part of the force to which the cable is subjected is shared uniformly over the fibers.

Abstract: A first frame produced by a first terminal is compressed after suppressing certain of the data fields forming it, then transmitted via a safe link through a transmission network into a second frame. This second frame received by a second terminal via the safe link is unpacked-from the fields relating to this safe link, whereupon the remainder of the frame is decompressed. The data fields suppressed for transmission by the first terminal are restored, either by calculation (for example, in the case of a frame checking sequence), or by insertion of a given word (for example, for each flag between frames). This data compressing and decompressing method is carried out in a data circuit-terminating equipment for a synchronous terminal.

Abstract: An adaptive threshold decision device for multistate modulation produces, at a symbol frequency, symbols dependent on the levels of a received demodulated baseband signal. It comprises a voltage divider, an adder for adding the baseband signal to a midpoint voltage which is substantially the mean of lower and upper voltages applied to the terminals of the voltage divider to produce a transposed signal, plural comparators for comparing the transposed signal with plural voltages at terminals of the voltage divider thereby producing comparison result signals, an encoder for deriving control words according to the comparison result signals, and control circuits for respectively and independently controlling at least the lower and upper voltages according to the control words.

Abstract: Coding and decoding of digital images by transformation of pixel blocks reduce the data bit rate. Transformation of blocks leads to discontinuities in brightness level for pixels bordering on block boundaries. These discontinuities are detected for each given bordering pixel by a change of sign of two level gradients respectively computed with the levels of two pixels adjacent to the bordering pixel. A brightness level of the bordering pixel is then corrected by a discontinuity correction factor evaluated from a discontinuity divergence equal to the absolute value of the difference between the brightness level of the bordering pixel and an arithmetical average of brightness levels of the two adjacent pixels, as a function of a quantization pitch associated with a block to which belongs the bordering pixel. The block is then corrected in its entirety to attenuate the differences of average brightness levels between two adjacent blocks generated by the coding and decoding.

Abstract: The phase/frequency comparator comprises a known phase comparator for comparing the phases of an digital input signal with a clock signal of which the period varies to within one time interval with respect to the period of the input signal. Such a phase comparator produces a first error signal whose sign, and preferably magnitude, vary as a function of the difference between the phases. The phase/frequency comparator is intended to produce a second error signal which replaces the first error signal and whose sign, and preferably magnitude, vary as a function of the difference between the periods. According to a preferred embodiment, a phase shift assessing circuit detects a predetermined phase shift, e.g. substantially equal to 0, between the clock signal and the input signal during a clock period.

Abstract: A detection assembly is disclosed for an infrared monitoring system, comprising a strip of elementary infrared detectors for analyzing the background of a scene. The elementary detectors are image formation detectors having sensitive areas smaller than the optical spots produced by the hot objects to be detected. The assembly comprises circuitry adapted for grouping together the image formation detectors virtually into virtual monitoring detectors having sensitive areas adapted to said optical spot, the grouping together circuitry comprising circuitry for summation in elevation of p contiguous intermediate image formation detectors at the pitch of q detectors with overlapping of p-q intermediate detectors from one monitoring detector to the next and circuitry for summation in relative bearing of r image formation samples at the pitch of s samples with an overlap of r-s samples from one monitoring pixel to the next.

Abstract: The present invention relates to scanning devices, for example those used in image scanning, observation and watching systems or else those used for example in aerial reconnaissance. The invention consists essentially in causing the mirror M to rotate about an axis distinct from the perpendicular to the plane of the rotating beam. In particular, this axis of rotation is set to an angle with respect to the perpendicular to the plane of the rotating beam, this angle being itself a function of the angle of incidence of the light beam.

Abstract: A wafer is provided for pre-processing the output currents of detection diodes subjected to thermal radiation, comprising an input stage for integrating the output currents of the diodes and an output stage delivering a signal related the incident radiation by a transfer function. It also comprises transistors for compressing the transfer function, the transistors conducting beyond a shunt threshold current less than a clipping threshold current and having a conduction resistance such as to shunt only a part of the integrated charges.

Abstract: A coherent optical detector has increased sensitivity for detecting a coherent optical signal by applying the coherent optical signal to be detected to a solid non linear medium pumped by two optical signals of opposite directions and coming from an auxiliary laser. The signal to be detected gives rise to an amplified signal applied with an auxiliary optical signal from the auxiliary laser, to a detector for causing these two optical signals to beat and detecting the beat and so the signal to be detected.

Abstract: A synchronizing device synchronizes a pseudo-binary signal particularly affected by high jitter with a regenerated clock signal into a synchronized signal. The device can be included between an output of a bipolar-to-binary converter receiving a plesiochronous bipolar signal and an input of a HDB/binary transcoder in a synchronizing circuit of a time-division multiplexer. The clock signal has a period Tj substantially lower than the nominal period of the pseudo-binary signal and offers phase jumps, particularly included between Tj/2 and Tj, for the clock signal to have a mean period equal to the nominal period.

Abstract: A system is disclosed for determining the position of at least one target by triangulation, comprising two passive sighting devices which measure the intensity of radiation received along a sighting line which scans a vertical sighting plane. They are disposed at a distance from each other along the same vertical axis and are driven in rotation about this common axis so that their sighting planes merge. A circuit extracts the angular coordinates of the target, relative to each of the sighting devices, and computes the distance of the target by triangulation in the vertical sighting plane.

Abstract: A device is divulged for generating an infrared image, in which an electron beam having a section substantially equal to the area of a pixel formed from a material having high emissive power in the infrared, directly bombards this material. The energy of the beam is transformed into heat then into infrared radiation, in the material. Each pixel is supported by a slab of a material transparent to the infrared, which is heat insulating and deposited on a screen transparent to the infrared and heat conducting.

Abstract: In order to spread optical fibers emerging from an end of cable and to firmly attach the cable end with ends of protective jackets in which the spread fibers are strung, the following steps are performed by means a spreading device including mainly a grooved hollow distributor. The distributor is fastened to a sawn off end of a grooved elongated ring in the cable by pinching a central armature emerging from the cable, by jaws housed in the distributor. A split ring is strung around a grooved revolution portion of the distributor. For each fiber, a longitudinal slot of the split ring and a respective groove of the revolution portion are superposed, the end of the jacket of the fiber is entered into the groove through the slot, and the jacket is forced into the groove by partially rotating the split ring so as to superpose the slot and another distributor groove.

Abstract: An apparatus accumulating a filiform element in order to absorb differences in input and output travel speeds of the element, without tangling and damaging the element. Mechanical means located above an accumulation container draw the filiform element at the input speed and wind the filiform element in layers of coils stacked on the bottom of the container following an epicycloid or hypocycloid path. Two stationary concentric rings, respectively, attached to and suspended above the bottom of the container, guide the filiform element unwound at the output speed through the bottom of the container to the outside. The apparatus is particularly designed for a very fine and fragile filiform element such as an optical fiber, and is inserted between a multifibering machine and a cabling line.

Abstract: The camera includes a chip of infrared detectors disposed in lines and a processing chip. The latter comprises integrators for integrating the output currents of the detectors, controlled by an automatic gain control loop for reducing the dynamic of the signal, delay lines, a summator for each line of detectors, error correction devices for reducing the fixed spatial noise errors, and a multiplexer receiving the signals associated with the various lines of detectors and furnishing a signal to a display device.

Abstract: The system according to the invention comprises a central microprocessor and peripheral microprocessors. A direct-access transfer memory is provided for the communication of the processors with one another. The memory is divided into as many distinct, determined zones as there are peripheral processors. The memory is connected to two addressing buses of which the latter serves equally well to address the boxes of the memory by the central microprocessor and to address the zones of the memory allocated to the peripheral microprocessors. The system is particularly well adapted to data transfers between a telephone automatic switch and subscribers' sets.

Abstract: A cryogenic device for radiation detectors is provided comprising an enclosure situated between a cryogenic cold finger supporting a detector and an external wall. After a brief degasification under vacuum of said enclosure, at least one gas is therein introduced, whose liquefaction or solidification temperature is higher than the temperature reached by said cold finger.