Abstract: A casing for housing a fiber optic transceiver for use in a fiber optic connector can include a top surface, a bottom surface and one or more lateral surfaces, wherein the top surface and at least one or more lateral surfaces are at least in parts electrically conductive, and wherein the bottom surface of the casing comprises one or more solder pads.

Abstract: An efficient coding and modulation system for transmission of digital data over plastic optical fibers is disclosed. The digital signal is coded by a three-level coset coding. The spectral efficiency of the system is configurable by selecting the number of bits to be processed in each of the levels. The first level applies to the digital data a binary BCH coding and performs coset partitioning by constellation mapping and lattice transformations. Similarly, second level applies another binary BCH coding, which may be performed selectably in accordance with the desired configuration by two BCH codes with substantially the same coding rate, operating on codewords of different sizes. The third level is uncoded. The second and third levels undergo mapping and lattice transformation. After an addition of the levels, a second-stage lattice transformation is performed to obtain a zero-mean constellation. The symbols output from such three-level coset coder are then further modulated.

Abstract: An efficient coding and modulation system for transmission of digital data over plastic optical fibres is disclosed. The digital signal is coded by a three-level coset coding. The spectral efficiency of the system is configurable by selecting the number of bits to be processed in each of the levels. The first level applies to the digital data a binary BCH coding and performs coset partitioning by constellation mapping and lattice transformations. Similarly, second level applies another binary BCH coding, which may be performed selectably in accordance with the desired configuration by two BCH codes with substantially the same coding rate, operating on codewords of different sizes. The third level is uncoded. The second and third levels undergo mapping and lattice transformation. After an addition of the levels, a second-stage lattice transformation is performed to obtain a zero-mean constellation. The symbols output from such three-level coset coder are then further modulated.

Abstract: The invention relates to a signalling method using orthogonal frequency division multiplexing (OFDM), based on a preamble comprising N dedicated carriers (frequency pilots), the position and modulation of which is defined by one or more concatenated complementary sequences of length N. Complementary sequences are those for which the sum of the autocorrelations thereof is zero except for zero shift, i.e. a Krönecker delta. The main purpose of said preamble is to signal the basic properties of the transmitted signal and to provide a first estimation at the moment of time and frequency synchronisation. The preamble is multiplexed or sequenced temporally with the transmitted data using OFDM prior to the application of the inverse Fourier transform by the inverse fast Fourier transform (IFFT) block.

Abstract: This process applies to a number of user kits (A, B, . . . X) and a head-end kit (1) communicating over the electricity network (2) using an upstream channel and a downstream channel. In essence, the process comprises accessing by multiple user kits (A, B, . . . X) in the upstream channel and the sending of multiple information frames by the head-end (1) in the downstream channel simultaneously applying OFDMA/TDMA/CDMA multiplexing and dynamically assigning each carrier so as to maximize transmission capacity in both the upstream and downstream channels. In turn, the process allows the adjustment of the quality of service according to the type of information and the user that requires the transmission and the dynamic allocation of bandwidth through constantly calculating the signal-to-noise ratio.

Abstract: The system enables bidirectional communication between a center and a plurality of users via a power line network and is characterized in that low and high speed communication can be established to provide multiple high-quality services to the users. The system comprises a performing network and frequency time-sharing and/or orthogonal frequency-division multiple access (OFDMA).

Abstract: Applicable to two-way communication over the electricity network between a plurality of user equipments (2) and a head-end equipment (1); characterized in that the receptors in the equipment (1, 2) continually monitor communication quality by estimating signal to noise ratio (S/N) in the individual carriers in the upstream and downstream channels. The user equipments monitor the state of the network at each moment in time independent of whether or not the transmission is destination for them. Optimum transmission mode is chosen as a result of this monitoring by means of modifying, packet by packet, the number of bits per carrier, the redundancy introduced by a FEC generator (forward error correction/detection), the FEC code, and/or the transmission mode; so as to achieve optimum sharing of the network in time and frequency at all times and to maximize the transmission capacity of the various user equipments by the network.

Abstract: This process applies to a number of user kits (A, B, . . . X) and a head-end kit (1) communicating over the electricity network (2) by means of an upstream channel and a downstream channel.

Abstract: The system enables bidirectional communication between a center and a plurality of users via the electric network and is characterized in that low and high speed communication can be established to provide multiple high-quality services to the users. The system comprises means to perform network and frequency time-sharing and/or orthogonal frequency-division multiple access (OFDMA).