Cselt-centro Studi E Laboratori Telecomunicazioni S.p.a.

Cselt- Centro Studi E Laboratori Telecommunicazioni Spa

Telecom Italia Lab S.p.a.

Cselt-centro Studi E Laboratori

Siemens Information & Communication Networks, Inc.

Italtel S.p.a.

Luciano Pilati

Piero Belforte

Bruno Bostica

Maura Turolla

Enzo Garetti

Mario Bondonno

Amilcare Bovo

Luigi Licciardi

Luigi Canato

Giancarlo Guaschino

Luigi Mori

Achille Montanaro

An RM unit for remultiplexing multi-program audio-video streams transmitted within an switched digital video broadcasting service includes: as, FL . . . FLn, MS . . . MSn syntactical analysis and reception means receiving plural streams, separating data packets in each stream that can be transported directly to CF, AA, MA, TU means for generating output streams, from service packets that must be transmitted to an MP control unit for processing, in particular for updating service information to reflect the composition of output streams; ME means for temporary storage of data packets, separately for each input stream; and CF; AA, MC, TU output stream generation means that generate and send service users single program output streams or multi-program streams at a lower band than input streams obtained starting from the packets stored in such ME temporary storage means and from the service packets processed and entered into virtual ATM channels.

Encoded audio-video streams remultiplexing equipment

The capacity of switching elements, for instance 8.times.8 elements, is expanded, to originate single-stage elements with greater capacity (16.times.16 or 32.times.32), by arranging an even plurality of such elements in an output substage and by placing upstream of the output substage at least a first input substage comprising a corresponding even plurality of the switching elements. The even and, respectively, the odd outputs of the elements of the input substage are connected in an orderly manner to the inputs of the switching elements of the output substage. A routing management logic to obtain single-stage elements is also provided within each individual switching element.

Method of expanding the capacity of switching elements, and switching

An automatic exchange of a telephone system comprises a PCM switching network with a plurality of cascaded stages for establishing temporal and spatial connections between incoming channels on input lines of the first stage and outgoing channels on output lines of the last stage in response to commands from external controllers dialoguing with internal controllers of the network. Pairs of switching matrices forming part of nonadjacent stages are combined into modular switching units each provided with its own internal controller. Routing instructions are transmitted from an external controller to a first internal controller which selects a signal path through the matrices of its own switching unit and informs a second internal controller of that selection whereupon the latter extends the path through an adjoining switching unit, and so on until the connection is completed. With digital message words such as speech bytes traveling in a forward direction from the input side to the output side of the network, the instruction words pertaining thereto move in the opposite direction over the same interstage links; the two paths are mutually conjugate within each switching unit, their matrices being bypassed by the routing instructions.

Modular self-routing PCM switching network for distributed-control

A switching unit for the selective transfer of bytes concurrently arriving in successive time slots over eight incoming signal paths to as many outgoing signal paths with intervening temporal and/or spatial transposition comprises a byte memory, loaded by way of a series/parallel converter and read out by way of a parallel/series converter, under the control of a routing memory dialoguing via a logic network with a microprocessor. The latter, through instructions sent to the logic network, may command the blocking of the readout from the byte memory onto an outgoing path during a given time slot, the insertion of a particular byte into such a time slot, or the transfer of selected bytes from either memory to the microprocessor itself. In particular, bytes from the first time slots of PCM frames arriving over selected signal paths can be so extracted from diagnostic purposes.

Switching unit for the transfer of digitized signals in PCM system

An automatic exchange of a telephone system comprises a PCM switching network with a plurality of cascaded stages for establishing temporal and spatial connections between incoming channels on input lines of the first stage and outgoing channels on output lines of the last stage in response to commands from external controllers dialoguing with internal controllers of the network. Pairs of switching matrices forming part of nonadjacent stages are combined ito modular switching units each provided with its own internal controller. Routing instructions are transmitted from an external controller to a first internal controller which selects a signal path through the matrices of its own switching unit and informs a second internal controller of that selection whereupon the latter extends the path through an adjoining switching unit, and so on until the connection is completed. Each matrix is provided with a data store which is asynchronously loadable from the associated internal controller with a routing instruction to be synchronously forwarded, in a special time slot dedicated to intercontroller dialoguing in a PCM group to which the instruction pertains, to the data store of a coacting matrix in the next stage for asynchronous retransmission to the controller thereof; each data store may be paired with a respective series/parallel converter coupling it to the associated matrix for serially loading that store in any PCM frame with the contents of the dedicated channels of concurrently arriving PCM groups and feeding stored instruction words in parallel to the output lines of the matrix during a predetermined time slot of each frame. The internal controllers also perform diagnostic operations by comparing bytes extracted from an established signal path at locations upstream and downstream of a matrix.

A five-stage PCM switching network of an automatic telephone exchange is divided into a set of outer modular units each including a first-stage and a fifth-stage matrix, a set of inner modular units each including a second-stage and a fourth-stage matrix, and a set of central modular units each including a pair of third-stage matrices. Each modular unit is provided with an individual base-level microprocessor controlling the switching of its matrices and the checking of their performance with the aid of ancillary equipment including transceivers sending back outgoing signals and samplers delivering bytes from corresponding time slots at opposite ends of an established signal path to a comparator in the associated microprocessor. Each set is divided into several subsets provided with respective intermediate-level microprocessors which control their base-level microprocessors; a top-level microprocessor, responsive to commands from a central controller, dialogues with the intermediate-level microprocessors for setting up and discontinuing calling connections between incoming PCM lines joined to inputs of the first-stage matrices and outgoing PCM lines joined to outputs of the fifth-stage matrices.

Modular structure for multistage PCM switching network

A switching unit for the selective transfer of bytes concurrently arriving in successive time slots over eight incoming signal paths to as many outgoing signal paths with intervening temporal and/or spatial transposition comprises a byte memory loaded by way of a series/parallel converter and read out by way of a parallel/series converter; two 8.times.8 storage matrices may alternately serve as the two converters. A routing memory, connected via a logic network to a command unit such as a microprocessor, controls the transfer and may also block the readout from the byte memory under certain conditions, specifically during an initiation procedure or where the switching unit is one of several such units forming part of a larger switching or concentration structure. In response to particular instructions from the command unit, a single byte from an incoming path may be transferred to one or all of the outgoing paths.

Growing community of inventors

Turin, Italy

Luciano Pilati