In-Network Data Aggregation for Ad Hoc Clustered Cognitive Radio Wireless Sensor Network.

Mohamad Rida Mortada,Koffi-Clément Yao,Ali Mansour,Abbass Nasser

doi:10.3390/s21206741

Abstract

In cognitive radio wireless sensor networks (CRSN), the nodes act as secondary users. Therefore, they can access a channel whenever its primary user (PU) is absent. Thus, the nodes are assumed to be equipped with a spectrum sensing (SS) module to monitor the PU activity. In this manuscript, we focus on a clustered CRSN, where the cluster head (CH) performs SS, gathers the data, and sends it toward a central base station by adopting an ad hoc topology with in-network data aggregation (IDA) capability. In such networks, when the number of clusters increases, the consumed energy by the data transmission decreases, while the total consumed energy of SS increases, since more CHs need to perform SS before transmitting. The effect of IDA on CRSN performance is investigated in this manuscript. To select the best number of clusters, a study is derived aiming to extend the network lifespan, taking the SS requirements, the IDA effect, and the energy consumed by both SS and transmission into consideration. Furthermore, the collision rate between primary and secondary transmissions and the network latency are theoretically derived. Numerical results corroborate the efficiency of IDA to extend the network lifespan and minimize both the collision rate and the network latency.

Highlights

Wireless sensor networks (WSNs) play an important role in several applications generating a large amount of data
We investigate the optimization of the cluster head (CH) number within a cognitive radio wireless sensor networks (CRSN) given several parameters, such as the in-network data aggregation (IDA), the energy consumption by physical sensing, energy consumed during the transmission, the SS performance that fulfils the predefined protection level for the primary user (PU) against the interference of the CRSN nodes, and the high spectrum efficiency to be exploited by these nodes
This network is divided into clusters and each cluster contains a number of nodes and one CH

Summary

Introduction

Wireless sensor networks (WSNs) play an important role in several applications generating a large amount of data. Like WSN, CRSN nodes consume energy to perform several operations: physical sensing, clustering election, data transmission, etc. We investigate the optimization of the CHs number within a CRSN given several parameters, such as the IDA, the energy consumption by physical sensing, energy consumed during the transmission, the SS performance that fulfils the predefined protection level for the PU against the interference of the CRSN nodes, and the high spectrum efficiency to be exploited by these nodes. 3. Probability of collision and the latency of our energy-optimal clustered CRSN are derived in closed forms, taken into consideration the data redundancy reduction thanks to the IDA.

Related Works

CRSN’s System Model

Problem Formulation

Maximal Consumed Energy

Numerical Results

Conclusions