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FPGA implementation of a configurable viterbi decoder for software radio receiver

Convolutional codes are one of the Forward Error Correction (FEC) codes that are used in every robust digital communication system. Viterbi algorithm is employed in wireless communications to decode the convolutional codes. Such decoders are complex and dissipate large amount of power. Software Defined Radio (SDR) is realized using highly configurable hardware platforms. Field Programmable Gate

Circuit Theory and Applications
Software and Communications

FPGA implementation of a reconfigurable Viterbi decoder for WiMAX receiver

Field Programmable Gate Array technology (FPGA) is a highly configurable option for implementing many sophisticated signal processing tasks in Software Defined Radios (SDRs). Those types of radios are realized using highly configurable hardware platforms. Convolutional codes are used in every robust digital communication system and Viterbi algorithm is employed in wireless communications to decode

Circuit Theory and Applications
Software and Communications

ARQ secrecy: From theory to practice

Inspired by our earlier work on Automatic Repeat reQuest (ARQ) secrecy, we propose a simple, yet efficient, security overlay protocol to existing 802.11 networks. Our work targets networks secured by theWired Equivalent Privacy (WEP) protocol because of its widespread use and vulnerability to a multitude of security threats. By exploiting the existing ARQ protocol in the 802.11 standard, our

Circuit Theory and Applications
Software and Communications

Authentication over noisy channels

An authentication counterpart of Wyner's study of the wiretap channel is developed in this work. More specifically, message authentication over noisy channels is studied while impersonation and substitution attacks are investigated for both single- and multiple-message scenarios. For each scenario, information-theoretic lower and upper bounds on the opponent's success, or cheating, probability are

Circuit Theory and Applications
Software and Communications

Comparison and analysis of water main performance models

Evaluating the condition state of infrastructure assets is one of the most integral pieces of information to the asset manager. Water infrastructure poses specific challenges compared to sewer infrastructure where techniques like CCTV are now being consistently used to assess condition. The number of water main breaks is commonly used as a proxy for water main condition. Statistical water main

Energy and Water

Hidden anchor: Providing physical layer location privacy in hybrid wireless sensor networks

In many hybrid wireless sensor networks (HWSNs) applications, sensor nodes are deployed in hostile environments where trusted and un-trusted nodes co-exist. In such hybrid networks, it becomes important to allow trusted nodes to share information, especially, location information and, at the same time, prevent un-trusted nodes from gaining access to this information. We focus on anchor-based

Software and Communications

Overlapping multihop clustering for wireless sensor networks

Clustering is a standard approach for achieving efficient and scalable performance in wireless sensor networks. Traditionally, clustering algorithms aim at generating a number of disjoint clusters that satisfy some criteria. In this paper, we formulate a novel clustering problem that aims at generating overlapping multihop clusters. Overlapping clusters are useful in many sensor network

Artificial Intelligence
Software and Communications

Novel reliability-based hybrid ARQ technique

In this paper we propose a novel technique for hybrid automatic repeat request (HARQ) systems where turbo codes are used as the forward error correction (FEC) techniques. This technique uses the histogram of the soft values generated by the turbo decoder to control the size and the contents of the retransmissions needed when the packet can not be decoded correctly. These soft values represent the

Artificial Intelligence
Software and Communications

Adaptive puncturing and rate selection in single-codeword turbo-coded OFDMA

This paper proposes using adaptive puncturing for rate-adaptive OFDMA systems utilizing turbo codes. The scheme is based on adaptively puncturing a Single Code Word (SCW) and hence adaptively changing the rate within the codeword. We compare the SCW against the Multiple Code-Words (MCWs) scheme where different rates are obtained by separate encoding, puncturing, and interleaving on a per-tile

Software and Communications

On the delay limited secrecy capacity of fading channels

In this paper, the delay limited secrecy capacity of the flat fading channel is investigated under two different assumptions on the available transmitter channel state information (CSI). The first scenario assumes perfect prior knowledge of both the main and eavesdropper channel gains. Here, upper and lower bounds on the secure delay limited capacity are derived and shown to be tight in the high

Software and Communications