In this paper, we for the first time demonstrate how to enable OFDMA in Wi-Fi backscatter capacity and concurrency enhancement. With our approach, excitation signal is reflected, modulated shifted lie frequency band of OFDM subcarrier by tag; realized coordinating tags convey information receiver with orthogonal subcarriers concurrently through backscatter. The crux design achieve strict synchronization among communication components, which more challenging than regular systems due prominent...

Recently proposed OFDMA backscatter could improve both concurrency and spectrum allocation flexibility for systems based on OFDM. However, we find that it is remarkably inefficient the existing design to scale up in prototyping: requires one-by-one offline computation obtain tags' operating parameters, order ensure orthogonality among subcarriers system; moreover, tag hardware has be dedicatedly modified before being assigned multiple subcarriers. The inefficiency caused by current analog...

OFDMA Wi-Fi backscatter can significantly improve the communication efficiency and meanwhile maintain ultra-low power consumption; however, ground-up reworking on core mechanism of traditional system revolutionizes basis many existing based mechanisms. In this paper, we explore how localization be realized backscatter, where a batch utilizing concurrent in is proposed. We present series mechanisms to deal with fundamental change assumptions brought by new paradigm. First, process signals at...

In this paper, we for the first time show how to enable software-defined PHY (SD-PHY) achieve agile reprogrammability in wireless backscatter networks. This can facilitate innovations field by relieving researchers from unnecessary engineering work. With SD-PHY, tag's PHY-layer behavior be neatly defined configuring a set of parameters, which allows common hardware generate backscattered signals complying with various protocols. The SD-PHY architecture is based on key insight that...

Backscatter tags have proven advantageous in reducing the power consumption of ultra-low upload data-rate IoT devices from milliwatts to tens microwatts [1, 2]. Previous backscatter ICs generally employ codeword translation and rely on incident signal being a modulated wave compliant with 802.11b [1] or utilizing modulation single tone generate that adheres established standards [2]. However, packet collisions occur conventional IC systems multiple following scenarios: 1) all synchronize...

This paper presents dual-band Wi-Fi backscatter (DBscatter), which is the first system supporting 2.4GHz and 5GHz simultaneously in a single tag. Our key insight that most existing devices communicate clean band. The band provides more chances for "free riding" with less interference, while better NLoS performance. DBscatter combines strengths of unexplored unified design, developing robust high-throughput ambient system. We make following technical contributions: (1) design RF frontend to...

This paper presents μTag, an ultra-low-power backscatter sensor that supports high-frequency sensing of a large number targets simultaneously. The core μTag is RF "gene editing" technique embeds both the identity and real-time motion state attached target intensively in transient features sensor's signal, collision-resilient manner. We provide practical techniques which i) generate such "genetic signal" with purely analog extremely simple circuits; ii) separate signals from scale sensors...

As a result of the growing complexity industrial Internet applications, traditional hardware-based network designs are encountering challenges in terms programmability and dynamic adaptability as they struggle to meet real-time, high-reliability transmission requirements for vast quantities data generated environments. This paper proposes holistic software-defined deterministic (HSDDN) design solution. solution uses centralized controller implement comprehensive software definition, ranging...

Chronic recording and stimulation in central peripheral nerves require both high mechanical biological compatibility. The biocompatible CNT yarn has shown promising advantage as a novel neural electrode. In this study, we quantitatively characterized the properties of electrodes from perspective flexural limit rigidity. traditional test configuration was remedied for ultrafine samples with efficient elimination bias caused by manual operation. As compared to Platinum-Iridium (Pt-Ir) wire...

OFDMA downlink design allowing parallel processing OFDM subcarriers is adopted by a number of commercial wireless standards such as LTE, 5G, and 802.11ax. However, the widespread adoption on low-end IoT devices stymied due to existing digital receiver framework's ≈100mW power consumption, which mainly incurred LO+mixer, ADC, complex processing. In this paper, we present an ultra-low-power demodulation design, achieves ≈100 μW receiving power. Our basic idea transform current approach into...

This paper presents FaB, a frequency-agile backscatter system that can optionally leverage OFDM signals on different bands as carriers for communication. Compared with existing systems are tailored to specific frequency band, yields two critical benefits: i) it the increased availability of "free rides" across broad range band improve its transmission efficiency; and ii) becomes compatible mainstream wireless communication standards, making applicable heterogeneous networks. Based these...

Under the background of tide innovation and entrepreneurship education, major electronic information takes on important task training high-level talents for progress science technology, development social technology provides motivation reform mode in colleges universities. Based analysis current situation practical teaching specialty “Application-oriented” talents, this paper probes into construction system specialty.

This paper presents MobiScatter, which enhances capacity of CSS based backscatter networks for accommodating drone-carried access points (APs). design has favorable features including long range and high concurrency. However, the concurrency network can be reduced by 34% when AP is introduced due to mobility fast fading. In order maintain concurrency, MobiScatter a series new designs. particular, we propose enhance with symmetric upchirps downchirps, neutralizes impact imperfect frequency...

In wireless sensor networks, nodes are inherently restricted by insufficient hardware resources, such as computing capacity and battery lifetime. As a result, current key management schemes difficult to be deployed in networks. This paper proposes new method that the shared keys dynamic updated for The proposed scheme loads two hash functions an initial into base station, cluster heads, nodes. Every node including heads authenticates its neighbor with key. Then every establishes pair wise...

Reconfigurable reflective arrays can be used to program the radio propagation environment in order form favorable wireless channel conditions. Previous designs have large-scale containing hundreds thousands of reflecting elements located external receiving node, with reflection coefficients all array managed by a controller. However, these costly deploy and are challenging quickly adapt time-varying nature channels caused mobility.