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Configurations of active acoustic metamaterial with programmable bulk modulus

Acoustic MetaMaterials (AMM) have been considered as effective means for controlling the propagation of acoustical wave energy through these materials. However, most of the currently exerted efforts are focused on studying passive metamaterials with fixed material properties. In this paper, the emphasis is placed on the development of a new class of one-dimensional acoustic metamaterials with

New achievable secrecy rate regions for the two way wiretap channel

This work develops new achievable rate regions for the two way wiretap channel. In our setup, Alice and Bob wish to exchange messages securely in the presence of a passive eavesdropper Eve. In the full-duplex scenario, our achievability argument relies on allowing the two users to jointly optimize their channel prefixing distributions, such that the new channel conditions are favorable compared to

Software and Communications
Innovation, Entrepreneurship and Competitiveness

A dynamic power-aware process variation calibration scheme

In this paper, a power-aware process variation calibration scheme is proposed. The proposed calibration system provides the ability to detect and control the n- and p-type variations independently through the use of all-n and all-p ring oscillators. Calibration is then carried out through the use of the supply voltage and body bias to alter the device parameters to match those of a certain process

Energy and Water
Circuit Theory and Applications

Propagation modeling for accurate indoor WLAN RSS-based localization

WLAN RSS-based localization has been a hot research topic for the last years. To obtain high accuracy in the noisy wireless channel, WLAN location determination systems usually use a calibration phase, where a radio map, capturing the signal strength signatures at different locations in the area of interest, is built. The radio map construction process takes a lot of time and effort, reducing the

Software and Communications

Configurations of active acoustic metamaterial with programmable bulk modulus

Acoustic MetaMaterials (AMM) have been considered as effective means for controlling the propagation of acoustical wave energy through these materials. However, most of the currently exerted efforts are focused on studying passive metamaterials with fixed material properties. In this paper, the emphasis is placed on the development of a new class of one-dimensional acoustic metamaterials with

Opportunistic interference alignment for multiuser cognitive radio

We present an interference alignment (IA) technique that allows multiple opportunistic transmitters (secondary users) to use the same frequency band of a pre-existing primary link without generating any interference. The primary and secondary transmit-receive pairs are equipped with multiple antennas. We exploit the fact that under power constraints on the primary transmitter, the rate of the

Software and Communications

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