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This paper introduces a new technique for aircraft identification friend or foe (IFF). The technique is based on using a proposed Chaos Advanced Encryption Standard (AES) with mode-S IFF. AES has a key size of 128 bits and a substitution-linear transformation network with 10 rounds. The sensitivity of the chaos initial condition gives the algorithm the ability to use as a second key. The first key...
OFDMA (Orthogonal frequency division multiple access) based systems have been considered as a candidate for future wireless communication systems. In such a system, it is important to provide high data rate services for users with high mobility. For this purpose, decision-directed channel tracking (DDCT) techniques have been investigated for OFDM systems in high mobility environments. The performance...
The application of an software agent-based computational technique that implements Extended Kohonen Maps (EKMs) for the management of Sensor-Actuator networks (SANETs) in health-care facilities. The agent-based model incorporates the BDI (Belief-Desire-Intention) Agent paradigms by Georgeff et al. EKMs perform the quantitative analysis of an algorithmic artificial neural network process by using an...
This paper proposes a cooperative spectrum sensing scheme for cognitive radio networks using a polynomial classifier. The proposed scheme utilizes either coherent or cyclostationary features in the received signal at each node and the extracted features are used by a central node to make to a global decision about the availability of spectrum holes for use by the cognitive radio network. The paper...
Principal component analysis (PCA) is known to be a powerful linear technique for data set dimensionality reduction. This paper focuses on revealing the essence of PCA to interpret the data, which is to identify the internal structure of the random process from a large experimental data set. We give an explanation of the PCA procedure performed on a generated data set to demonstrate the exact meaning...
Two numerical approaches, the Robust-Generalized Iterative Approach (R-GIA) and the Robust-Transmit Covariance Optimization Approach (R-TCOA), are proposed for jointly designing the minimum mean square error (MMSE) precoders and decoders of uplink multiuser multiple-input-multiple-output (MIMO) systems with arbitrary linear equality power constraints and possibly imperfect channel state information...
In this paper, we investigate the impact of the transmit spatial correlation on the performance of the spatial multiplexing Multiple-Input Multiple-Output (MIMO) Multi-User (MU) Ultra-WideBand (UWB) system in which a pre-equalizer and a Time Reversal (TR) pre-filter are deployed at the transmitter. The combination of the pre-equalizer and the pre-filter is to mitigate the Multiple-Stream Interference...
This paper proposes five new estimators for the Bit Error Rate (BER), which have no closed form expression. Here, in particular, we focus on the case for coherent Differential Quaternary Phase Shift Keying (DQPSK), with Gray coding, over an Additive White Gaussian Noise (AWGN) channel, where the instantaneous BER can be expressed in a form involving the standard Marcum Q-function. By exploiting several...
Artificial neural networks (ANN) are known for their ability to solve classification and optimization tasks and have been applied in many fields of communications such as equalization and multiuser detection, among others. In this paper an analog realization of iterative threshold decoding for binary linear codes is presented. It is shown that the iterative threshold decoding algorithm matches well...
In this paper we evaluate a recently proposed multiple-input multiple-output (MIMO) system called the Layered Steered Space-Time Codes (LSSTC). The LSSTC system is evaluated for multi-user environments where scheduling can be used to increase the system capacity by harnessing the multi-user diversity. This evaluation is done by comparing the capacity and the probability of error for several combinations...
Photoacoustic imaging is a high resolution, biomedical imaging modality used for cancer detection and imaging biological tissues. Exact photoacoustic reconstruction methods were proposed for simple geometries in both time and frequency domain. However, for arbitrary geometries only time reversal methods were previously proposed. In this paper, we propose a frequency domain algorithm for photoacoustic...
An efficient algorithm for non-rigid image registration is proposed. The proposed method consists of two-stage registration process, which is based on affine transformation in both local and global registration. Numerical examples demonstrated that the proposed method provides more accurate registration results than global registration methods.
In this paper, we propose the low-complexity FPGA implementation of a reconfigurable successive interference cancellation (SIC) detector for combating the effect of multiuser interference in wired/wireless systems. The complexity of various building blocks is reduced and then the whole structure is pipelined. Using the PXI-7842R platform from National Instruments, the SIC detector is implemented and...
Human beings have a remarkable ability to determine the direction of arrival of a sound and to separate sounds of interest. Replicating this ability is a challenging problem in audio signal processing. In this paper we present a model for the head related transfer function (HRTF) developed with the localisation objective in mind. This is achieved by splitting the 3D localisation cues in terms of two...
A novel generalized iterative approach (GIA) is proposed for jointly designing the MMSE MIMO processors (precoders, relay processors and decoders) for the analog Network Coding scheme. The MMSE performance can be achieved for MIMO communication links with two end nodes and multiple relay nodes subject to either the per-node power constraint or the practical per-antenna power constraint. Numerical...
A novel approach was developed to recognize vowels from continuous tongue and lip movements. Vowels were classified based on movement patterns (rather than on derived articulatory features, e.g., lip opening) using a machine learning approach. Recognition accuracy on a single-speaker dataset was 94.02% with a very short latency. Recognition accuracy was better for high vowels than for low vowels....
In this paper, it is proposed to design and implement a physical layer Unequal Error Protection (UEP) scheme based on convolutional codes and asymmetric 8PSK modulation. This scheme is combined with the UEP schemes at the application layer that is, multi-level unequal importance of compressed H.264/AVC video data. The proposed scheme takes the prioritized H.264 video data and encodes them with equal...
Signal strength (SS) based tag estimation significantly improves the accuracy and speed of RFID tag interrogation. In, SS estimation was applied to a Manchester based RFID system and a formula for the lower bound on number of tags was derived. This paper analytically extends this analysis to a comprehensive list of encoding formats including all those used in commercially available tags. The developed...
We study in this paper the resource allocation matter for unlicensed multiband ultra-wideband (UWB) users in the context of high-rate wireless personal area network (WPAN). The problem is viewed as a coexistence problem with existing licensed systems. The QoS support and the interference mitigation are jointly considered in this study to derive a novel interference power control mechanism that differentiates...
With the provisioning of interworked heterogeneous wireless networks and the growing popularity of smart mobile devices, ubiquitous service and data access is showing a demanding growth. As a result, scenarios of group mobility evolved with the increasing trend where a number of commuters on a transportation carriage would access such services. Making this scenario further complex, there was also...
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