ENC-MAC: Energy-efficient Non-overlapping Channel MAC for Cognitive Radio enabled Sensor Networks

Abstract

The concept of Internet of Things (IoT) has shed new light on WSN technologies. MAC protocol issues improving the network performance are important in WSNs because of the increase in demand for various applications to secure spectrum resources. Cognitive radio (CR) technology is regarded as a solution to the problems in this future wireless network. In recent years, energy efficiency has become an issue in CR networks. However, few relevant studies have been conducted. In this paper, an energy-efficient non-overlapping channel MAC (ENC-MAC) for CR-enabled sensor networks (CRSNs) is proposed. Applying the dedicated control channel approach, ENC-MAC allows the SUs to utilize channels in a non-overlapping manner, and thus spectrum efficiency is improved. Moreover, the cooperative spectrum sensing that allows an SU to use only two minislots in the sensing phase is addressed to enhance energy efficiency. In addition, an analytical model for evaluating the performance, such as saturation throughput, average packet delay, and network lifetime, is developed. It is shown in our results that ENC-MAC remarkably outperforms existing MAC protocols.

Hybrid Full Frequency Precoding for Integrated Remote Wireless Sensor and Multibeam Satellite Networks

“…[20] proposed SNs with MIMO receivers that perform a nonlinear operation on the complex valued received signal, which possessed the low cost, low power and low complexity that were crucial for sensor networks. [21] considered an energy efficient non-overlapping channel MAC to be utilized for WSNs, which improved spectrum efficiency and energy efficiency. [22] exploited the spatial and temporal correlation between sensor data for WSNs, the spatial redundancy of sensor data is reduced by similarity based sub clustering, where closely correlated SNs are represented by a single representative node.…”

“…However, the MIMO precoding assumed that one terminal was served per beam for each time slot by employing time division multiplexing (TDM), and explicitly stated that a set of terminals were served per beam for each time slot as an open problem to be studied [25]- [27]. Precoding for MSNs in the existing research mainly considered throughput maximization as the optimization objective, while TPM problem and MMF problem are the hot research area in the WSNs [20] [21] and MIMO systems [28]- [31]. Thus, considering energy consumption is a crucial factor of WSNs, the HFF precoding problem is formulated as TPM and MMF problems.…”