Abstract: The present invention relates to a planar antenna carried by a substrate including a slot (11) consisting of a closed curve dimensioned in order to operate at a given frequency and fed by a feed line (12) positioned so that the slot lies in a short-circuit plane of the feed line. This antenna includes, in parallel on the slot 11, at least one switching means 13 capable of assuming a closed state or an open state so as to modify the operating frequency band of the planar antenna. This antenna is particularly suitable for domestic wireless networks.

Abstract: A stereophonic processing system provided with spatial expansion of the stereophonic sound so that a pair of spaced-apart loudspeakers will acoustically appear to be spaced apart further then they actually are. The spatial expansion circuit includes tonal compensation.

Abstract: Planar antenna carried by a substrate comprising an annular slot, which is dimensioned to operate at a given frequency and which is fed via a line (2), such as a microstrip line, in a short-circuit plane of which the slot is situated. The annulus formed by this slot (1a), is deformed as indentations in at least one zone of the plane in which the electric field is a minimum for the given frequency and a given mode, this making it possible to obtain a lengthening of the slot perimeter with respect to an annular slot (1), of corresponding circular shape, without surface extension of the substrate zone wherein the slot is made.

Abstract: The present invention relates to a device for the reception and/or the transmission of electromagnetic signals comprising at least two means of reception and/or of transmission of electromagnetic signals of the slot-fed antenna (11a, 11b, 11c, 11d) type and means of connection for connecting at least one of the said means of reception and/or of transmission to means of utilization of the multibeam signals, in which the means of connection consist of two feed lines (12, 13) connected by a connection element to the utilization means (P), the two lines being coupled electromagnetically with the slots of the slot-fed antennas, each line terminating in a switching element (14, 15) arranged in such a way as to simulate, as a function of a monitoring signal, an open circuit or a short circuit at the extremity of one of the lines and a short circuit or an open circuit at the extremity of the other line so as to obtain different radiation patterns.

Abstract: The invention relates to a method for displaying screen elements on a reproduction screen. A predetermined number of pixels (Pa1 . . . Pej) of a reproduction line (L1 . . . Lm) are combined to form a cell (C11 . . . Cmn). A reproduction line (L1 . . . Lm) is formed from a fixedly predetermined number of cells (C11 . . . Cmn).