Abstract:
Synchronizing circuit including a variable delay circuit (DLC) through which an input signal (DIN) is passed to adjust the phase of a regenerated output signal (DIN1) with respect to a clock signal (CL1) at the frequency of the input signal, and a decision circuit (DC) to adjust the variable delay (DL1/8) so that it covers half a period of the input signal and after having detected a predetermined lack of synchronism modifies the value of the variable delay such that this delay may then be adjusted to cover the second half of the period.
Abstract:
A switching system (SW) to transfer packets of digital signals having a header containing routing information from a plurality of input terminals (R1 to R16) to a plurality of output terminals (T1 to T16), the destination output terminal for a packet being selected according to the routing information of this packet. The system includes a plurality of memories (M1 to M8) which are each subdivided into a plurality of storage areas each associated to a respective output terminal, receiver circuits (RC1 to RC16) to divide each received packet into a plurality of sub-packets, control circuits (CC1 to CC8) and transmitter circuits (TC1 to TC16) to rebuilt a packet from its sub-packets. Under the control of the control circuits operating according to the routing information of a packet the sub-packets belonging to this packet are transmitted to respective ones of the memories and loaded into the storage area thereof corresponding to the destination output terminal.
Abstract:
Method and means for porting an existing application (An) using a relational-database with SQL interface toward a hardware platform (HW2) with a reduced software configuration which does not include an SQL relational-database. The invention emulates an SQL database enabling hardware resources saving and providing a subset of functions in order to: creating SQL tables and defining fields; storing, modifying and deleting data on created tables, with a type check, retrieving such data by using SQL filters. Functions can be subdivided into levels (M1, M2, M3) in order to: convert an SQL statement, coming from an existing user application (An), into a sequence of elementary interface functions (IF1...IFn), use said interface functions to read/write data files (F1...Fn), process output data to be supplied to the requesting user application (An).
Abstract:
For any pair of individual objects (i, j) and each relationship that may exist therebetween, a management device comprises a memory element RMP(i, j) for storing the existence or absence of said relationship. The memory element comprises an input corresponding to a first object (i) and an input corresponding to a second object (j), said inputs being connected to two respective individual buses (CC(j), LC(i)). The two inputs must receive two respective simultaneous commands to enable data indicating the existence or absence of a relationship between the objects to be written into the element. In a preferred embodiment, the input corresponding to the first object must receive a read signal to enable the memory element to deliver the data to an output corresponding to the second object, and the input corresponding to the second object must receive a read signal to enable the memory element to deliver the data to an output corresponding to the first object. If the relationship is symmetrical, said memory elements are arranged in a triangular network (TN'). The device may be used in switching systems for asynchronous transfer mode telecommunications.
Abstract:
Radio access communications system in the fixed subscriber loop (CEB, EB, ATR) providing access for a set of subscriber terminals (TE) to a fixed telephone network (RTF). This communications system establishes an audio channel link, in addition to that for signalling, over which pass, as information in the voice band, the tone signals associated with the call control signals pertaining to the fixed telephone network (RTF) and the dialling signals generated by the subscriber terminals (TE) for calls made by said subscriber terminals (TE) towards said fixed telephone network (RTF). The communications system supports the call control functions corresponding to the fixed telephone network (RTF) and the two-wire subscriber interface control functions of the subscriber terminals (TE).
Abstract:
An MDP-8 differential encoder for trellis-coded modulations, as well as a corresponding pragmatic decoder, enabling phase ambiguities of 90 DEG , 180 DEG and 270 DEG to be lifted, in particular for use in the high-speed radio transmission of images.
Abstract:
A device for selecting a primary satellite for a terminal (T) in a radiocommunication system having a number of moving satellites comprises measurement means for determining location information (D) on the basis of the position of the terminal with respect to each of the neighboring satellites (S1, S2, S3) on which it has becomed synchronized, estimation means for estimating the period of visibility of each of the satellites on the basis of the location information, and selection means for selecting the satellite (S2) having the longest estimated visibility.
Abstract:
There is a considerable need for optical fibre amplifiers for the wavelength range around 1300 nm for information transmission. The basic material for the amplifier light guide (10) needed therefor is to be silicon dioxide. The doping agents neodym and praseodym normally used for the desired wavelength range are, however, not suitable as they stand to obtain the required amplification. According to the invention, neodym or praseodym is used in combination with fluorine, preferably as the compound NdF3 or PrF3. In a preferred production process, an easily evaporable complex is formed from NdF3 and a further compound, e.g. AlF3, and taken in vapour form to a substrate for a deposition from the vapour phase.
Abstract:
A protection circuit for protecting circuit elements (TX) connected to line via terminal means (L1 and L2) from the effects of a transient abnormal high voltage surge, comprising a semiconductor switch (TR1, TR2), a first circuit comprising a resistor (R1) in series with the conductor path of the semiconductor switch and a voltage reference means (D1, D2) in parallel with the resistor and a junction of the semiconductor, and a second circuit comprising the first voltage reference means in series with a second voltage reference means (D3), the second circuit being connected in parallel with the resistor. The second circuit further includes a voltage dependent resistance (VC1). When the current through the resistor exceeds normal line current the voltage reference means (D1, D2, D3) clamp the voltage drop across the resistor and turn off the semiconductor switch.
Abstract:
A method of adjusting the pulse rate of a local clock (1) by generating a first pulse train at a first predetermined rate, dividing the pulse train by a divisor (3) to produce a second pulse train. The value of the divisor (3) is selected (4, 5, 6) so that the rate of the second pulse train is adjusted within a predetermined range.