The purpose of this article is to show the suitability of asynchronous automata as the formal model for the specification of architectural patterns and particular architectures. Independence of actions, which occurs naturally in asynchronous automata, has direct relevance in architectural descriptions. We demonstrate this via a sequence of examples. The aim of this exercise is to identify a sui...

In this paper, we propose a direct sequence ultra wideband (DS-UWB) radar system using a short-length pseudo noise (PN) sequence. The proposed DS-UWB radar reduces the correlation processing time by averaging out the noise in the correlator outputs, and thus, employs a short-length PN sequence unlike the conventional DS-UWB radar systems using multiple variable-length PN sequences. Numerical re...

We consider the problem of training-based code-timing estimation for the asynchronous direct-sequence code-division multipleaccess (DS-CDMA) system. We propose a modified large-sample maximum-likelihood (MLSML) estimator that can be used for the code-timing estimation for the DS-CDMA systems over the resolvable multipath channels in closed form. Simulation results show that MLSML can be used to...

Multi-user receivers in asynchronous Direct Sequence Code Division Multiple Access (DS-CDMA) systems require the knowledge of several parameters such as timing delay between users. The goal of this work is to present a QHDU IDU resistant joint multi-user synchronization and detection algorithm for DSCDMA systems. The solution is based on the Conditional Maximum Likelihood (CML) estimation metho...

Different modulation schemes supporting multiple data rates in a Direct Sequence Code Division Multiple Access (DS-CDMA) system are studied. Both AWGN and multipath Rayleigh fading channels are considered. It is shown that the multi processing-gain scheme and the multi-channel scheme have almost the same performance. However, the multi-channel scheme may have some advantages due to easier code ...

A novel implementation of Inter process communication in CDMA NOC is proposed. In this study, the orthogonality properties of a Walsh code are used to route data packets between the IP-Cores.The asynchronous circuit design with combinational logic (Gate level design) is used for transmission and receiving circuits, along with ip-cores and reduces the processing time and resource utilization. Th...

This paper presents a parallelized architecture of multiple classifiers for face detection based on the Viola and Jones object detection method. This method makes use of the AdaBoost algorithm which identifies a sequence of Haar classifiers that indicate the presence of a face. We describe the hardware design techniques including image scaling, integral image generation, pipelined processing of...

We consider combined rate and power adaptations in direct-sequence code-division multiple-access communications, where the transmission power and the data rate are adapted relative to channel variations. We discuss the power gain that the combined adaptations provide over power adaptation. Then, we consider an integrated voice and data transmission system that offers a constant bit rate voice s...

The need for a robust method that protects owner rights against unintended or malicious stealing, which has arisen because of the rapid increase of Internet data exchange and multimedia use, in addition to international electronic commercial services and the multimedia that it contains, has become a substantial constraint to the research in this domain. This paper proposes a novel method for im...