An efficient algorithm for image segmentation based on a multi-resolution application of a wavelets transform and feature distribution is presented. The original feature space is transformed into a lower resolution with a wavelets transform to derive fast computation of the optimum threshold value in a feature space. Based on this lower resolution version… (More)
A new adaptive thresholding algorithm concerning extraction of targets from the background in a given image sequence is proposed. The conventional histogram-based or fixed-value thresholdings are deficient in detecting targets due to the poor contrast between targets and the background , or to the change of illumination. This research solves the problems… (More)
A critical issue in applications involving networks of wireless sensors is their ability to synchronize, and mitigate the fading propagation channel effects. Especially when distributed " slave " sensors (nodes) reach-back to communicate with the " master " sensor (gateway), low-power cooperative schemes are well motivated. Viewing each node as an antenna… (More)
the novel training patterns lead to further decoupled CFO and channel estimators. The performance of our algorithms is investigated analytically, and then compared with an existing approach by simulations.
— We design pilot symbol assisted modulation for carrier frequency offset (CFO) and channel estimation in orthogonal frequency division multiplexing (OFDM) transmissions over multi-input multi-output (MIMO) frequency-selective fading channels. By separating CFO and channel estimation from symbol detection, the novel training patterns lead to low-complexity… (More)
— This letter analyzes the implementation issues related to coherent receivers for UWB impulse radio with a special emphasis on timing and jitter problems. We propose a new jitter tolerant receiver design that is easy to implement. Analytical BER analysis and simulations verify that the performance of the proposed receiver is comparable to that of a… (More)
In this paper, we propose a novel method of blind signal separation using a new performance criterion with nonlinear separating functions, and derive an adaptive algorithm. The criterion consists of nonlinear mappings of output signals and their cumulants for independence of the signals. We show that our method requires a weak condition for stable… (More)
—This paper proposes to encode pilot bits together with information bits by using a systematic encoder and applying them to an iterative receiver, where channel estimation and decoding are iteratively performed. This paper then shows why and how the encoded pilot bits can give a positive gain over a conventional uncoded pilot system. Specifically, this… (More)