Abstract: An interferometer, such as a Mach-Zehnder type is fed with a pulse train. One arm is fed with a data stream, so as to modulate the pulse train according to the data stream. This enables the data stream to be regenerated, or sampled without converting from optical form into electrical form. Thus all optical regeneration, multiplexing, demultiplexing or retiming to remove jitter, can be achieved. An optical amplifier (20) in one arm of the interferometer enables the interference condition of the interferometer to be varied, to cause the pulse train to be modulated by the data.

Abstract: In a process for regulating a refrigeration system (1) using an expansion valve (4), one side of the regulating member is pressed by the pressure of refrigerant at the evaporator side and the other side of the regulating member is pressed by the vapor pressure of a sensor system (22) whose sensor temperature is determined by the refrigerant saturation temperature and by the heat supplied by a heating element (27). heat supply is regulated depending on a measurement value (overheating or liquid level). Also disclosed is a refrigeration system (1) regulated in this manner and an expansion valve (4) as essential component of such a system. An improved, exonomic and universally applicable regulation can thus be obtained.

Abstract: The present invention provides an auxiliary or side lobe cancelling antenna particularly for horizontally polarised main antennas. The auxiliary antenna arrangement for cancelling side lobe interference from a main antenna comprises a ground plane shaped in a concertina or zig-zag fashion. Dipole pairs are spaced from and arranged perpendicular to the front bends, the dipoles having ends angled towards corresponding ground plane sections. The dipoles are connected anti-phase to provide a radiation pattern approximating an ideal auxiliary antenna mask of the main antennas pattern.

Abstract: A method of forming glass uses the steps of forming base glass from layered stacks of colored glass; V-Grooving a plurality of base glass layers; stacking the grooved layers; heating and maintaining at an elevated temperature for flow and air entrainment elimination; recutting the block to desired dimensions and reforming into sheet form. The glass has ribbons of color contained within a glass matrix, the ribbons being aligned perpendicularly to the face of the glass.

Abstract: The present invention provides a layered antenna (otherwise known as a flat-plate antenna) having a number of radiating elements (201), each radiating element comprising a first substantially rectilinear aperture (210), having a first pair of oppositely directed probes (220,222) extending into an area defined by the aperture with secondary apertures (212,214) arranged coextensive with and on opposite sides of the primary aperture, adjacent said first pair of probes, said secondary apertures operable to modify the beamwidth in a plane coextensive with said first pair of probes. There is also provided a method of receiving and transmitting signals by means of a layered antenna of this construction.

Abstract: Arbitration apparatus is described for arbitrating between a number of jobs, for example for distributing message traffic over a data transmission network. The arbitration apparatus comprises an activity register containing a number of activity bits indicating which of a number of transmission jobs is currently active. The apparatus also includes a two-tier token ring arrangement comprising an outer ring and a number of inner rings. Each ring consists of a number of registers, holding a token which is passed cyclically around the ring. Each register has a bypass path which bypasses the register if a corresponding job or group of jobs is inactive. The positions of the tokens in the rings determines which job is to be scheduled next. Each ring also includes a keeper register for preserving the token if all the jobs are inactive.

Abstract: A method for marshalling an additional outstation (3) of a time division multiple access (TDMA) telecommunications system including a basestation (4) and a plurality of outstations (1, 2), such as a passive optical network (PON). A sequence is transmitted from the additional outstation (3) to the basestation (4) at a level below the noise sensitivity of a receiver (49) of the basestation (4), detected at the basestation and its phase discrimated. From the discriminated phase the loop delay to the additional outstation is determined and the outstation instructed to realign its transmission accordingly. The sequence and its phases are detected by a correlation process. (FIG. 1).

Abstract: A structure for the shielding of electronic components from outside electromagnetic fields is to be designed in such a way tha a single printed circuit board serves both to separate a "polluted" space from a "clean" space and to accommodate the components of the device to be shielded itself. To this end, the printed circuit board has a first region which is provided with an internal, grounded conductive coating, and a second region which carries the electronic components to be shielded. A housing forms a shielding partition which extends to the printed circuit board and has an end face engaging the printed circuit board between the first and second regions. The first chamber is limited by the first region of the printed circuit board. Shielding for blocking electromagnetic fields are provided in the printed circuit board adjacent partition. These shielding extend transversely to the surfaces of the printed circuit board.