Abstract
Collaborative beamforming (CB) enables uplink transmission in a wireless sensor network (WSN) composed of sensors (nodes) and far-away access points (APs). It can also be applied to the case where the sensors are equipped with beam-switching structures (BSSs). However, as the antenna arrays of the BSSs are randomly headed due to the irregular mounting surface, some sensors form beams that do not illuminate a desired AP and waste their limited energy. Therefore, to resolve this problem, it is required to switch the beams toward the desired AP. While an exhaustive search can provide the globally optimal combination, a greedy search (GS) is utilized to solve this optimization problem efficiently. Simulation and experimental results verify that under certain conditions the proposed algorithm can drive the sensors to switch their beams properly and increase the received signal-to-noise ratio (SNR) significantly with low computational complexity and energy consumption.
Highlights
The omnidirectional radiation causes weak connectivity and strong interference between sensors [25,26]. These drawbacks can be alleviated by utilizing directional antennas which provide the additional performance enhancement in terms of energy, throughput, spectrum, and security [27,28,29], directional antennas may not be suitable for sensors due to their reduced angular coverage and unsteerable radiating directions, as seen in Figure 1b [30]
Through simulations and experiments, it is verified that the proposed algorithm can increase the signal-to-noise ratio (SNR) considerably, and is applicable in an embedded system having a Micro Controller Unit (MCU), which is widely used for wireless sensors
It is assumed that each sensor in a wireless sensor network (WSN) is equipped with a beam-switching structures (BSSs)
Summary
To enable wireless sensors in IoT [18] to sense the surrounding environment over a wide frequency spectrum, integrated sensing circuits composed of magnetic [19], thermal [20], visual [21], infrared [22], and acoustic [23] radars are embedded in them It is anticipated that a serious reduction of the received power at the AP, resulting from the absence of some sensors in the CB, will occur To avoid this problem, there are two approaches: (1) each sensor performs the beam switching in turn, or (2) all of the sensors do it simultaneously in a random manner. Through simulations and experiments, it is verified that the proposed algorithm can increase the SNR considerably, and is applicable in an embedded system having a Micro Controller Unit (MCU), which is widely used for wireless sensors
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
