Practical Backscatter with Commodity BLE

Recently, backscatter technology has attracted much interest in wireless communication due to its novel low-cost and battery-free design. Since Bluetooth Low Energy (BLE) was born to be low energy consumption, great efforts have been made in BLE-based backscatter systems, like FreeRider, RBLE. In this paper, we present BonusBlue, a BLE backscatter system that enables high-goodput communication with commercial BLE devices. BonusBlue tag generates BLE packets by modulating data on excitation signals and set up a data connection with BLE receiver using a state machine, thus achieving a high-goodput communication link. We present this state machine design and build a prototype of our tag using an FPGA, and evaluate its performance with BLE devices. Our evaluation shows that the backscatter tag can build a robust data connection link with commodity BLE device in the guidance of our state machine and transmit tag data on this link. Experimental results show that our backscatter system can achieve a goodput of up to 16.9 kbps.

The Bluetooth Low Energy (BLE) is an attractive solution for implementing low-cost, low power consumption, short-range wireless transmission technology and high flexibility wireless products, which working on standard coin-cell batteries for years. The original design of BLE is restricted to star topology networking, which limits network coverage and scalability. In contrast, other competing technologies like Wi-Fi and ZigBee overcome those constraints by supporting different topologies such as the tree and mesh network topologies. This paper presents a part of the researchers’ efforts in designing solutions to enable BLE mesh networks and implements a tree network topology which is not supported in the standard BLE specifications. In addition, it discusses the advantages and drawbacks of the existing BLE network solutions. During analyzing the existing solutions, we highlight currently open issues such as flooding-based and routing-based solutions to allow end-to-end data transmission in a BLE mesh network and connecting BLE devices to the internet to support the Internet of Things (IoT). The approach proposed in this paper combines the default BLE star topology with the flooding based mesh topology to create a new hybrid network topology. The proposed approach can extend the network coverage without using any routing protocol.

Bluetooth low energy (BLE) is a promising candidate technology for use in the Internet of Things (IoT) because of its ultra-low-power communication. Although BLE devices are designed to run on a small battery for a few years, several attempts have been made to extend BLE lifetime through various techniques. In particular, emerging approaches such as artificial intelligence (AI) can be utilized to further improve the BLE energy efficiency. For this purpose, this article proposes a Q-learning-based scheduling algorithm for BLE. The proposed scheduling algorithm dynamically adjusts the key parameters that govern the operation of the BLE transmission scheme. These key parameters, namely, the length of connection interval and the number of packets to transmit during the interval, have a profound effect on energy efficiency and the quality of service (QoS) specified in terms of maximum latency. According to the framework of reinforcement learning, our Q-learning-based scheduling algorithm is appropriately constructed to simultaneously provide a longer network lifetime and satisfy the QoS requirement. The numerical results show that the proposed Q-learning-based approach significantly increases the network lifetime compared to alternative methods while meeting QoS requirements.

With the rapid development of Internet of Things (IoT) technologies, Cross-Technology Communication (CTC) has become a key method for establishing direct links between heterogeneous wireless systems. Existing CTC approaches typically rely on emulating the waveform of the target signal; however, such emulation often faces precision limitations due to bandwidth differences, mismatched modulation schemes, and hardware non-idealities. This paper proposes WiBlue, a CTC scheme that enables direct wireless data transmission from Wi-Fi devices to Bluetooth Low Energy (BLE) devices. The approach is based on the IEEE 802.11n physical layer and uses cyclic prefix (CP) processing, quadrature amplitude modulation (QAM), and frequency compensation mechanisms to achieve efficient compatibility across heterogeneous physical layers. WiBlue has been implemented on the USRP B210 platform with commercial BLE devices. Experimental results show that WiBlue achieves high reliability in various indoor environments, maintaining a packet reception rate above 96 % and a symbol error rate below 0.2, demonstrating its practicality and stability for heterogeneous wireless communication.

This paper investigates the possibility to develop a Bluetooth Low Energy (BLE) device as part of Internet of Things chain. For this purpose, both the hardware and the software aspects are considered. Thus, the BLE software stack from Texas Instruments and the CC2541 platform were chosen. Considering the CC2541 Keyfob device which contains an accelerometer, new facilities are firstly introduced by modifying the existing embedded software. Then, a new hardware component is connected, and the necessary software components are included in order to use this new element. The two main applications that are employed to monitor the activity of the BLE devices are analyzed and a new one based on MATLAB is introduced to improve the facilities of the existing applications. Thus, using the ideas presented in this paper, new BLE devices can be developed.

The rapid and increasing application of wireless technology, especially Bluetooth Low Energy (BLE), provides many benefits to our daily lives. With BLE, the small packets of data can be exchanged over a wireless channel, whereas the data security is a concern. For example, the BLE standards define that if one BLE device with input-output capabilities tries to establish a connection while the other BLE device does not support input-output, an unauthenticated channel will be established. That is, in the worst case, the connection is established where no security is applied. To mitigate this issue, we propose a security protocol, named BALSAPro, at the application layer that complements the existing protocols such as Security Manager Protocol (SMP), which can help establish a secure channel with authentication and non-repudiation, when pairing has not been used. In the evaluation, we implement and evaluate our protocol performance compared with similar work at the application layer. The results demonstrate that our protocol can enhance the security level with less time consumption.

Beacons turn the physical world into a new digital channel. They bring digital content and engagement closer to the point of purchase. Beacon technology transmits small packets of data using Bluetooth Low Energy. When a customer’s phone “hears” the beacon it knows how close it is and we can then send a message, a notice, a piece of media or other information. Beacons are low-power transmitters equipped with Bluetooth Low Energy or BLE. Bluetooth Low Energy help mobile devices to detect Proximity and determine micro-location. Advantages of Bluetooth low energy devices are it works up to 100 meters, doesn’t drain the phone battery.In this paper problems with beacon are described and path navigation using Bluetooth Low Keywords: Beacon , Internet of Things – Beacons The New Revolution, Bluetooth Low Energy, Path Navigation, Background Monitoring, Ranging Beacons, Proximity, Tracking

Future telecommunications aim to be ubiquitous and efficient, as widely deployed connectivity will allow for a variety of edge/fog based services. Challenges are numerous, e.g., spectrum overuse, energy efficiency, latency and bandwidth, battery life and computing power of edge devices. Addressing these challenges is key to compose the backbone for the future Internet-of-Things (IoT). Among IoT applications are Indoor Positioning System and indoor Real-Time-Location-Systems systems, which are needed where GPS is unviable. The Bluetooth Low Energy (BLE) 5.1 specification introduced Direction Finding to the protocol, allowing for BLE devices with antenna arrays to derive the Angle-of-Arrival (AoA) of transmissions. Well known algorithms for AoA calculation are computationally demanding, so recent works have addressed this, since the low-cost of BLE devices may provide efficient solutions for indoor localization. In this paper, we present a system topology and algorithms for self-localization where a receiver with an antenna array utilizes the AoAs from fixed battery powered beacons to self-localize, without a centralized system or wall-power infrastructure. We conduct two main experiments using a BLE receiver of our own design. Firstly, we validate the expected behaviour in an anechoic chamber, computing the AoA with an RMSE of <inline-formula> <tex-math notation="LaTeX">$\mathrm {10.7~ ^{circ}}$ </tex-math></inline-formula>. Secondly, we conduct a test in an outdoor area of 12 by 12 meters using four beacons, and present pre-processing steps prior to computing the AoAs, followed by position estimations achieving a mean absolute error of <inline-formula> <tex-math notation="LaTeX">$\mathrm {3.6~ \text {m}}$ </tex-math></inline-formula> for 21 map positions, with a minimum as low as <inline-formula> <tex-math notation="LaTeX">$\mathrm {1.1~ \text {m}}$ </tex-math></inline-formula>.

Bluetooth Low Energy (BLE) is a popular low power wireless technology, used for short-range communication. In BLE networks, discovery process enables fast and energy-efficient communication, since all communications must involve it at the first step. For this reason, some studies have proposed novel discovery schemes to improve the performance of device discovery process. Nevertheless, literature report that provides a consolidated view are limited and insufficient. In this paper, we survey different device discovery schemes in BLE networks and discuss their advantages and limitations. The enhanced schemes are categorized into two approaches: parameter adjustment and collision avoidance approach. The first approach improves the performance by adjusting the discovery parameters according to a network situation. In the second approach, the BLE devices try to avoid the interference to reduce collisions in crowded networks.

This paper proposes a new indoor positioning algorithm for Bluetooth Low Energy (BLE) devices, such as mobile phones and tablets. The algorithm integrates an Off-set triangulation algorithm and a multi-stage weighted framework. An off-set triangulation algorithm was used to provide a general method to locate the user’s position. Results are integrated into a weighted framework in order to increase the adaptability of the proposed localization algorithm to different complex environments and increase the accuracy of the localization. Three experiments in different environments have been examined in order to test the performance and the limitations of this algorithm. Results show that the proposed algorithm demonstrated strong adaptability to complex non-Line-of-Sight (LOS) environments.

With the popularization of Internet-of-things (IoT) and wireless communication systems, a diverse set of applications in smart cities are emerging to improve the city-life. These applications usually require a large coverage area and minimal operation and maintenance cost. To this end, the recently emerging backscatter communication (BC) is gaining interest in both industry and academia as a new communication paradigm that provides high energy efficient communications that may even work in a battery-less mode and, thus, it is well suited for smart city applications. However, the coverage of BC in urban area deployments is not available, and the feasibility of its utilization for smart city applications is not known. In this article, we present a comprehensive coverage study of a practical cellular carrier-based BC system for indoor and outdoor scenarios in a downtown area of a Helsinki city. In particular, we evaluate the coverage outage performance of different low-power and wide area technologies, i.e., long range (LoRa) backscatter, arrow band-Internet of Things (NB-IoT), and Bluetooth low energy (BLE) based BC at different frequencies of operation. To do so, we carry out a comprehensive campaign of simulations while using a sophisticated three-dimensional (3D) ray tracing (RT) tool, ITU outdoor model, and 3rd generation partnership project (3GPP) indoor hotspot model. This study also covers the energy harvesting aspects of backscatter device, and it highlights the importance of future backscatter devices with high energy harvesting efficiency. The simulation results and discussion provided in this article will be helpful in understanding the coverage aspects of practical backscatter communication system in a smart city environment.

The new direction-finding feature incorporated in version 5.1 of the Bluetooth Core Specification accelerates the development of applications in the context of the Internet of Things (IoT) for indoor localization and asset tracking. We evaluate the position of the Bluetooth Low Energy (BLE) transmitter based on the angle of arrival (AoA) mechanism proposed by the Bluetooth standard using Software Defined Radio (SDR). The system is comprised of a phased array antenna, an analog section for the conversion of Radio Frequency (RF) signals to the baseband, followed by a digital section for AoA estimation. The experimental results validate the proposal with precise estimates and a high resolution for the AoA. The proposed approach can be used for digital beamforming to increase the operating range or decrease the level of power consumed by BLE devices in IoT applications.

Bluetooth Low Energy (BLE) is a widely adopted wireless communication technology in the Internet of Things (IoT). BLE offers secure communication through a set of pairing strategies. However, these pairing strategies are obsolete in the context of IoT. The security of BLE based devices relies on physical security, but a BLE enabled IoT device may be deployed in a public environment without physical security. Attackers who can physically access a BLE-based device will be able to pair with it and may control it thereafter. Therefore, manufacturers may implement extra authentication mechanisms at the application layer to address this issue. In this paper, we design and implement a BLE Security Scan (BLESS) framework to identify those BLE apps that do not implement encryption or authentication at the application layer. Taint analysis is used to track if BLE apps use nonces and cryptographic keys, which are critical to cryptographic protocols. We scan 1073 BLE apps and find that 93% of them are not secure. To mitigate this problem, we propose and implement an application-level defense with a low-cost $0.55 crypto co-processor using public key cryptography.

This demonstration shows how inexpensive, off-the-shelf, and unobtrusive Bluetooth Low Energy (BLE) devices can be utilized for enabling robots to recognize touch gestures, to perceive proximity information, and to distinguish between interacting individuals autonomously. The received signal strength (RSS) between the BLE device attached to the robot and BLE devices attached to the interacting individuals is used to achieve this. Almost no software configuration is needed and the setup can be applied to most everyday environments and robot platforms.

We present BumbleBee, a novel backscatter system that creates ZigBee transmissions over productive Bluetooth Low Energy (BLE) carriers. In contrast to prior content-aware or non-productive backscatter, BumbleBee overwrites tag information independently on any ambient BLE. The backscattered signal is dominated by the tag information and compliant with commodity ZigBee radios. Since BLE signals are widespread, BumbleBee enables the vision of pervasive ZigBee backscatter communication. We prototype BumbleBee using commodity BLE transmitters, an off-the-shelf FPGA, and commodity ZigBee receivers. Through extensive experiments and field studies, we show that BumbleBee works universally with ambient BLE and commodity receivers. Further, when the signal strength is -80 dBm, BumbleBee has a throughput of 218 kbps and 204 kbps in the line-of-sight (LOS) and nonline-of-sight (NLOS) scenarios, respectively. The throughput improvement is up to 3x compared with the advanced non-productive backscatter system, Interscatter [1], and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$32\mathrm{x}$</tex> over the content-aware backscatter system, FreeRider [2]. The bit error ratio (BER) is below 1% when the tag-to-receiver distance is 20 meters. As the first ambient ZigBee backscatter system that works universally with commodity transceivers, we believe BumbleBee takes a crucial step towards pervasive ZigBee backscatter communication.