This article evaluates the quality-of-service performance and scalability of the recently released Bluetooth mesh protocol and provides general guidelines on its use and configuration. Through extensive simulations, we analyze the impact of the configuration of all the different protocol’s parameters on the end-to-end reliability, delay, and scalability. In particular, we focus on the structure of the packet broadcast process, which takes place in time intervals known as Advertising Events and Scanning Events . Results indicate a high degree of interdependence among all the different timing parameters involved in both the scanning and the advertising processes and show that the correct operation of the protocol greatly depends on the compatibility between their configurations. We also demonstrate that introducing randomization in these timing parameters, as well as varying the duration of the Advertising Events , reduces the drawbacks of the flooding propagation mechanism implemented by the protocol. Using data collected from a real office environment, we also study the behavior of the protocol in the presence of WLAN interference. It is shown that Bluetooth mesh is vulnerable to external interference, even when implementing the standardized limitation of using only 3 out of the 40 Bluetooth low-energy frequency channels. We observe that the achievable average delay is relatively low, of around 250 ms for over 10 hops under the worst simulated network conditions. However, results prove that scalability is especially challenging for Bluetooth mesh since it is prone to broadcast storm, hindering the communication reliability for denser deployments.

Understanding the Performance of Bluetooth Mesh: Reliability, Delay, and Scalability Analysis

Bluetooth Low Energy (BLE) Mesh Networks enable flexible and reliable communications for low-power Internet of Things (IoT) devices Most BLE-based mesh protocols are implemented as overlays on top of the standard Bluetooth star topologies while using piconets and scatternets Nonetheless, mesh topology support has increased the vulnerability of BLE to security threats, since a larger number of devices can participate in a BLE Mesh network To address these concerns, BLE version 5 enhanced existing BLE security features to deal with various authenticity, integrity, and confidentiality issues However, there is still a lack of detailed studies related to these new security features This survey examines the most recent BLE-based mesh network protocols and related security issues In the first part, the latest BLE-based mesh communication protocols are discussed The analysis shows that the implementation of BLE pure mesh protocols remains an open research issue Moreover, there is a lack of auto-configuration mechanisms in order to support bootstrapping of BLE pure mesh networks In the second part, recent BLE-related security issues and vulnerabilities are highlighted Strong Intrusion Detection Systems (IDS) are essential for detecting security breaches in order to protect against zero-day exploits Nonetheless, viable IDS solutions for BLE Mesh networks remain a nascent research area Consequently, a comparative survey of IDS approaches for related low-power wireless protocols was used to map out potential approaches for enhancing IDS solutions for BLE Mesh networks

https://www.mdpi.com/1424-8220/20/12/3590/pdf

Bluetooth Low Energy Mesh Networks: Survey of Communication and Security Protocols

The rapid development of wireless technology has sparked interest in multi-band reconfigurable antennas as devices and satellites are innovating toward miniaturization. With limited space, reliable and efficient high bandwidth antenna systems are needed for current and next-generation wireless technology as well as for the revolutionary small satellites. The fifth generation of mobile communication technology promises high data rates, low latency and good spectrum efficiency. One of the key enablers of this technology is the integration of satellite technology-particularly CubeSats with terrestrial communication technologies. Next-generation antennas that can meet functional requirements for 5G and CubeSat applications are therefore of fundamental importance. These antenna systems should have large bandwidth, high gain and efficiency and be compact in size. Reconfigurable antennas can provide different configurations in terms of the operating frequency, radiation pattern and polarization. Tuning reconfigurable antennas can be done by changing the physical parameters of the antenna elements through electronic switches, optical switches and the use of meta-materials. The most popular implementation method for reconfigurable antennas for wireless and satellite communication is the electronic switching method due to its high reliability, efficiency, and ease of integration with microwave circuitry. In this article, different techniques for implementing reconfigurable and multi-band antennas are reviewed, with emphasis on two main application areas; 5G wireless communication and CubeSat application. Different reconfiguration techniques have been studied for application in various wireless communication systems such as satellite communication, multiple-input multiple-output (MIMO) systems, cognitive radio and 5G communication. It has been found that reconfigurable antennas have favourable properties for next-generation wireless technology and small satellites. These properties include low cost, less volume requirements and good isolation between wireless standards. 

/pdf/multiband-reconfigurable-antennas-for-5g-wireless-and-3e0s1x11.pdf

Multiband Reconfigurable Antennas for 5G Wireless and CubeSat Applications: A Review

The rapid development of wireless technology has sparked interest in multi-band reconfigurable antennas as devices and satellites are innovating toward miniaturization. With limited space, reliable and efficient high bandwidth antenna systems are needed for current and next-generation wireless technology as well as for the revolutionary small satellites. The fifth generation of mobile communication technology promises high data rates, low latency and good spectrum efficiency. One of the key enablers of this technology is the integration of satellite technology-particularly CubeSats with terrestrial communication technologies. Next-generation antennas that can meet functional requirements for 5G and CubeSat applications are therefore of fundamental importance. These antenna systems should have large bandwidth, high gain and efficiency and be compact in size. Reconfigurable antennas can provide different configurations in terms of the operating frequency, radiation pattern and polarization. Tuning reconfigurable antennas can be done by changing the physical parameters of the antenna elements through electronic switches, optical switches and the use of meta-materials. The most popular implementation method for reconfigurable antennas for wireless and satellite communication is the electronic switching method due to its high reliability, efficiency, and ease of integration with microwave circuitry. In this article, different techniques for implementing reconfigurable antennas are reviewed, with emphasis on two main application areas; 5G wireless communication and CubeSat application. Different reconfiguration techniques have been studied for application in various wireless communication systems such as satellite communication, multiple-input multiple-output (MIMO) systems, cognitive radio and 5G communication. It has been found that reconfigurable antennas have favourable properties for next-generation wireless technology and small satellites. These properties include low cost, less volume requirements and good isolation between wireless standards.

https://ieeexplore.ieee.org/ielx7/6287639/6514899/09754587.pdf

Multi-Band Reconfigurable Antennas For 5G Wireless and CubeSat Applications: A Review

Bluetooth Mesh (BM) is a new communication protocol for the Internet of Things that is used to establish many-to-many device communication. BM allows for easy creation of large connection-less mesh networks using a controlled-flooding propagation mechanism, in which relay nodes broadcast the received messages to all neighbors until the message reaches its destination. This model, however, makes BM networks susceptible to broadcast-storm effects, which can hinder the scalability of the protocol. Opportune relay node selection is therefore of critical importance to control network traffic and improve network performance. This paper focuses on the choice of relay selection algorithms suitable for BM networks. In particular, different centralized, decentralized, and localized algorithms based on Connected Dominating Set (CDS) are evaluated and compared.

Relay Node Selection in Bluetooth Mesh Networks

Bluetooth Mesh (BM) is a new communication standard, which is designed for the upcoming Internet of Things. It builds on the Bluetooth Low Energy (BLE) protocol and allows devices to extend the range and create a mesh network. BM introduces a publisher/ observer structure where a publisher node can broadcast a packet, known also as an advertisement, and all observers can receive the packet. Typically, in BM networks flooding is used to propagate the advertisements. Flooding is known to suffer from broadcast storm problem and be nonreli-able. To improve packet delivery ratio we propose an approach where only a few nodes, relays, are involved in packet forwarding. Selection of the relay nodes, which is a focus of the paper, is a nontrivial task: on the one hand, a minimization of number of relays is desired, on the other hand, using a minimum dominated set would not provide redundancy. We consider three different relay selection mechanisms and develop their extensions that are capable to operate in a distributed fashion. Their performance is evaluated via extensive simulations.

On Relay Selection Approaches in Bluetooth Mesh Networks

This paper presents the simulated performance of a dual S- and X-band shared aperture antenna design. The antenna is 82 by 82 mm and it has a total height of $\leq 4$ mm. This size allows the antenna to fit within the parameters of a nano-satellite unit structure. The antenna is right hand circularly polarized in both bands. The Antenna is tuned to a S-band frequency range from 2.025 to 2.075 GHz and a X-band frequency range from 7.75 to 8.75 GHz. The design has a Realized right hand circularly polarized gain of $\geq$6dB in the S-band and $\geq$12dB in the X-band. The impedance bandwidth is very wide as it exceeds the selected frequency ranges. The cross-coupling is below -25dB in the S-band and below -30dB in the selected X-band frequency range.

/pdf/shared-aperture-dual-s-and-x-band-antenna-for-nano-satellite-4senlhvuhc.pdf

Shared Aperture Dual S- and X-band Antenna for Nano-Satellite Applications

This paper presents a dual S- and X-band antenna structure and gives a detailed performance evaluation of the antenna design. The main benefit of the presented antenna is its high frequency-ratio and its low cross-coupling. The antenna measures 82×82mm and has a total thickness of 5.65mm. The antenna is fabricated using Rogers-RT5870 substrate material. The small footprint of the presented antenna makes it very suited for nano-satellite applications. The desired S-band frequency range is from 2.00 to 2.12GHz. The desired X-band frequency range is from 8.2 to 9.0GHz. The Fabricated antenna prototype is measured to have a sufficient impedance bandwidth and a low axial ratio. The cross-coupling is both simulated and measured to be below -40dB in the desired frequency range. The antenna has a realized right hand circularly polarized gain of more than 6.0dBi and more than 12.0dBi in the desired frequency ranges of the S-band and X-band, respectively.

Dual S- and X-Band Shared Aperture Antenna for Nano-Satellite Applications

This paper presents a circularly polarized dual-band shared aperture antenna for satellite applications. The antenna achieves dual S- and Ka-band operation by housing both a circularly polarized high-frequency reflectarray and a circularly polarized low-frequency patch antenna array in the same aperture area. The high-frequency reflectarray part of the antenna has unit elements within the aperture area of the low-frequency patch antenna array which allows for a high realized high-frequency gain. The antenna has a layered structure with a middle layer of Polypropylene, this enables the low-frequency part of the antenna to achieve a wide impedance bandwidth and a high realized gain. The antenna has a total size of $136\times 136\ \text{mm}$ and the three layers of the reflective surface have a total height of 4.624 mm. The antenna has an impedance bandwidth of more than 415 MHz (12%) and 4.75 GHz (19%) and a peak realized gain of 14.80 dBi and 26.68 dBi at 3.5 GHz and 25.4 GHz, respectively.

Circularly Polarized Shared Aperture Reflectarray and Patch Antenna Array for S- and Ka-Band

In this paper, an indoor Ultra Wide Band (U localization system relying on a single-anchor setup is prese Conventional UWB localization systems require at least i anchors for trilateration, which leads to high system complexity and cost. Hence new technologies, such as the Virtual An (VA) approach are emerging to achieve single-anchor localiza The VA concept models Multipath Components (MPCs individual distance measurements thus exploiting reflections the environment to aid the accuracy of the localization. Exi single-anchor approaches require a priori information of pre” tag positions to estimate the current tag position. The novelty of this paper is an initialization method that enables estimate tag position without the use of a priori position information. The proposed solution is validated using both simulations and measurements. Both simulations and measurements have shown positive results, which indicates that single-anchor location is feasible.

Daniel E. Serup

Papers

On Relay Selection Approaches in Bluetooth Mesh Networks

Shared Aperture Dual S- and X-band Antenna for Nano-Satellite Applications

Dual S- and X-Band Shared Aperture Antenna for Nano-Satellite Applications

Circularly Polarized Shared Aperture Reflectarray and Patch Antenna Array for S- and Ka-Band

An indoor multipath-assisted single-anchor UWB localization method