Nec Laboratories America, Inc.

Columbia University

Kai Li

Xiaodong Wang

Mohammad Madihian

Guosen Yue

A cross-layer optimization framework for designing of multi-radio/multi-channel wireless mesh networks with network coding to support multiple unicast applications is used. A column-generation-based primal-dual method is used to solve the optimization problem. For network-layer formation, a code construction scheme based on linear programming is used. Delay constraints are imposed on the network code construction so the possible impact of the extra decoding delay to the upper-layer Transmission Control Protocol/Internet Protocol (TCP/IP) performance may be reduced without changing the upper-layer protocols.

Method and apparatus for optimization of wireless mesh networks

Methods and systems for digital wireless communication are provided.

Methods and systems for digital wireless communication

A method for selecting a signal to noise ratio for a communications code includes obtaining extrinsic information transfer (EXIT) information for a repeat-zigzag Hadamard (RZH) code responsive to a Hadamard order and a signal to noise ratio, determining code parameters for an irregular repeat zigzag Hadamard (IRZH) code for a corresponding code rate in response to the obtained EXIT values, and repeating the step of obtaining the EXIT information for a different signal to noise ratio if the corresponding code rate is other than a selected rate. The corresponding code rate is related to a bit error rate. In a preferred embodiment, the step of obtaining EXIT information includes one of obtaining an EXIT curve for repeat-zigzag Hadamard code by Monte Carlo simulation using serial decoding or obtaining an EXIT function for parallel decoding of the repeat-zigzag Hadamard code by using equations.

Code design method for repeat-zigzag Hadamard codes

An encoder includes an outer repetition encoder, an interleaver for permuting encoding from said outer repetition encoder; and an inner encoder for encoding information from the interleaver to provide a repeat zigzag-Hadamard code. In an exemplary embodiment, a common bit of a zigzag-Hadamard segment of encoding from said inner encoder is a repetition of a last parity bit of a previous zigzag-Hadamard segment of encoding from said inner encoder and said common bit is punctured.

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New York, NY, United States of America

Kai Li