X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/ThesisAli.git/blobdiff_plain/525e119b40cf9c06a207f28ed96e8b3253365325..28fe5f530e0e9ae044a4463fd7eb3646cc5dd04c:/CHAPITRE_01.tex diff --git a/CHAPITRE_01.tex b/CHAPITRE_01.tex index b6b4a4b..ec27e65 100644 --- a/CHAPITRE_01.tex +++ b/CHAPITRE_01.tex @@ -13,7 +13,7 @@ \label{ch1:sec:01} %The wireless networking has received more attention and fast growth in the last decade. In the last decade, wireless networking has became a major component of the global network infrastructure. -More precisely, the growing demand for the use of wireless applications and the continuous arrival of wireless devices such as portable computers, cellular phones, and personal digital assistants (PDAs) have led to develop different infrastructures of wireless networks. The wireless networks can be classified into two classes based on the network architecture~\cite{ref154,ref155}: Infrastructure-based networks that consist of a fixed network structure such as cellular networks and wireless local-area networks +More precisely, the growing demand for the use of wireless applications and the continuous arrival of wireless devices such as portable computers, cellular phones, and Personal Digital Assistants (PDAs) have led to develop different infrastructures of wireless networks. The wireless networks can be classified into two classes based on the network architecture~\cite{ref154,ref155}: Infrastructure-based networks that consist of a fixed network structure such as cellular networks and Wireless Local-Area Networks (WLANs); and Infrastructureless networks that are constructed dynamically by the cooperation of the wireless nodes in the network, where each node is capable of sending packets and taking decisions based on the network status. Examples of such type of networks include mobile ad hoc networks and wireless sensor networks. Figure~\ref{WNT} shows the taxonomy of wireless networks. \begin{figure}[h!] @@ -51,7 +51,7 @@ Figure~\ref{twsn} shows the components of a typical wireless sensor node~\cite{r \item \textbf{Computation Unit:} The main purpose of this unit is to manage and manipulate the instructions that are related to sensing, communication, and self-organization. This allows the sensor node to cooperate with other sensor nodes in order to perform the allocated sensing tasks. It is composed of a processor chip, an active short-term memory for storing the sensed data, an internal flash memory for storing program instructions, and an internal timer. -\item \textbf{Communication Unit:} It is responsible for all data transmission and reception done by the sensor node, which are performed by the transceiver circuitry. A transceiver circuit is composed of a mixer, frequency synthesizer, voltage-controlled oscillator (VCO), phase-locked loop (PLL), demodulator, and power amplifiers. All these components consume valuable power~\cite{ref19}. +\item \textbf{Communication Unit:} It is responsible for all data transmission and reception done by the sensor node, which are performed by the transceiver circuitry. A transceiver circuit is composed of a mixer, frequency synthesizer, Voltage-Controlled Oscillator (VCO), Phase-Locked Loop (PLL), demodulator, and power amplifiers. All these components consume valuable power~\cite{ref19}. \item \textbf{Power Unit:} This unit represents the most significant part of a sensor node. It supplies the other units by the needed power.