Maxim Integrated Products, Inc.

Nortel Networks Corporation

Kaveh Razazian

Maher Umari

Victor Loginov

Amir Hosein Kamalizad

Michael V Navid

Afshin Niktash

Qi Qu

Kenneth E Garey

Christina K Chan

Lois Marie Greer

Nathan Goldstick

Jiang Yue

Farshad Meshkinpour

Xiao Ling Chang

Victor V Loginov

A power line communication (PLC) device includes a physical layer module including a transceiver configured to transmit and receive data over a power line. A medium access control (MAC) module is configured to send data to and process data from the physical layer module. The MAC module includes a channel access module configured to initiate a channel access attempt. The channel access module successively is configured to increase a random backoff period for a subsequent channel access attempt based on a random backoff function in response to a determination by the physical layer module that a PLC channel is busy during a preceding one of the channel access attempts. The channel access module successively is configured to selectively reset a variable in the random backoff function based on an output of a modulo function of a number of backoff attempts and a predetermined number.

Power line communication device with channel load measurement and improved channel access

A receiver for a power line communication (PLC) device includes an analog front end configured to receive an input signal from a power line. The input signal includes symbols and wherein each of the symbols includes samples. A demodulator module is configured to demodulate the input signal to generate a demodulated signal. The demodulator module includes an impulse noise module configured to detect and remove impulse noise in the symbols of the input signal.

Impulse noise detection and cancellation in power line communication device

According to one embodiment of the invention, an integrated circuit comprises an encoding module, a modulation module and a spectral shaped module. The encoding module includes an interleaver that adapted to operate in a plurality of modes including a first mode and a second mode. The interleaver performs repetitive encoding when placed in the second mode. The modulation module is adapted to compensate for attenuations that are to be realized during propagation of a transmitted signal over the power line. The spectral shaped module is adapted to compensate for amplitude distortion and further compensates for attenuations that will be realized during propagation of the transmitted signal over the power line.

System and method for applying multi-tone OFDM based communications within a prescribed frequency range

A power line communication (PLC) system includes a source node, a plurality of intermediate nodes and a destination node. Each of the source node, the plurality of intermediate nodes and the destination node comprise a PLC interface including a medium access control (MAC) module and a physical layer (PHY) module. A transformer is located between the source node and the destination node. Routing modules of the source node, one or more of the intermediate nodes, and the destination node establish a route from the source node to the destination node via one or more selected ones of the plurality of intermediate nodes. The route is selected using a route cost that is calculated based on link costs of a plurality of hops in the route from the source node to the destination node. The link costs are based on forward link costs and reverse link costs.

Routing for power line communication systems

A method to detect a phase connection of a receiver of a power line communication system includes providing a first connection between a transmitter and one phase of a multi-phase power line. A zero crossing of a first signal provided by the first connection is detected. A first timestamp is generated before a packet is transmitted by the transmitter and added to a header of the packet. A second connection is provided between the receiver and one phase of the multi-phase power line. A zero crossing of a second signal provided by the second connection is detected. A second timestamp is generated when the packet is received by the receiver. The value of the first timestamp is compared to the value of the second timestamp to determine whether the one phase of the first connection is the same as the one phase of the second connection.

Transmitter and method for applying multi-tone OFDM based communications within a lower frequency range

An apparatus to process an input signal received via a power line in a power line communication system includes a jammer remover and a jammer detector. The jammer remover removes interference resulting from transmission of electricity and the input signal over the power line from the input signal. The jammer remover generates a jammer-canceled signal using an adaptive filtering procedure. The jammer detector is coupled to the jammer remover to detect the interference.

Jammer canceller for power-line communication

An embodiment is a method and apparatus to decode a signal using channel information. A channel state estimator generates a tone value representing channel information. A quantizer quantizes the tone value. A combiner combines de-interleaved symbols weighed by the quantized tone value. A comparator compares the combined de-interleaved symbols with a threshold to generate a decoding decision. Another embodiment is a method and apparatus to decode a signal using averaging. A channel estimator provides a channel estimate. A multiplier multiplies a quantized output of a demodulator with the channel estimate to produce N symbols of a signal corresponding to a carrier. A de-interleaver de-interleaves the N symbols. An averager averages the N de-interleaved symbols to generate a channel response at a carrier.

Soft repetition code combiner using channel state information

According to one embodiment of the invention, an integrated circuit comprises an encoding module, a modulation module and a spectral shaped module. The encoding module includes an interleaver that adapted to operate in a plurality of modes including a first mode, a second mod and a third mode. The interleaver performs repetitive encoding when placed in the second mode and even greater repetitive encoding when placed in the third mode.

An embodiment is a method and apparatus to estimate channel quality. An absolute processor computes absolute real and imaginary values of real and imaginary parts, respectively, of output of a demodulator. A phase count unit generates first and second phase counts representing deviations from zero phase noise using the absolute real and imaginary values. An amplitude count unit generates first and second amplitude counts representing attenuation of a received signal using the absolute real and imaginary values. An integrator integrates the first and second phase counts and first and second amplitude counts into a signal quality indicator that represents a measure of quality of channel with respect to noise and fading.

Blind channel quality estimator

An embodiment is a method and apparatus to interleave data. A demultiplexer demultiplexes an input packet having N bits into L sub-packets on L branches. M flipping blocks flip M of the L sub-packets. M is smaller than L. L sub-interleavers interleave the (L-M) sub-packets and the M flipped sub-packets. A concatenator concatenates the interleaved sub-packets to form an output packet.

Block interleaving scheme with configurable size to achieve time and frequency diversity

An embodiment is a method and apparatus to perform symbol synchronization. A sign element obtains signs of samples in a sample vector. A correlation estimator computes a correlation of the sample vector. A synchronization detector detects symbol synchronization. Another embodiment is a method and apparatus to perform frame synchronization. A Fast Fourier Transform (FFT) processing unit computes a current FFT vector and an accumulated previous FFT vector. The current FFT vector and the accumulated previous FFT vector correspond to sample vectors associated with preamble symbols prior to symbol synchronization detection. A real and imaginary processing unit generates real and imaginary summations using the current FFT vector and the accumulated previous FFT vector. A mode processor generates mode flags representing operational modes using the real and imaginary summations.

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Aliso Viejo, CA, United States of America

Kaveh Razazian