Wireless Network Adapter Research Articles

Personal Cloud Storage using Raspberry PI

Developing a Raspberry Pi personal cloud server that can serve as your very own personal cloud storage is the goal of the project "Personal Cloud Using Raspberry Pi." Moving your data to private cloud storage is a preferable solution because privacy protection is a major concern today. The Raspberry Pi 3 model B module that houses the cloud server is configured. The server is linked to the internet by the router. For greater data storage, the server offers an optional USB hard disc. The Raspberry Pi server's wireless network card or adapter is used to link it to Personal Cloud, an open-source cloud computing platform. The Raspberry Pi can be configured remotely from any device, such as a smartphone, using a local tunnel.Numerous services, including SSH, HTTP, and VNC, are configured on and managed by the local tunnel. Access to the Personal Cloud account is restricted to the admin. Through the local tunnel, an administrator can provide users a variety of services. You can store your data for free on our project as needed. With tight system control, this project provides you the freedom to use space efficiently.

Reducing interference via link adaptation in delay-critical wireless networks

One of the current (6G) wireless networks research’s trends is to investigate short distance and dense scenarios, where users are locally connected in sub-networks. Such use case is critical to support the advances of industrial internet of things or Industry 4.0 (I4.0), e.g. connecting an entire group of sensors and actuators of a robot. Therefore, schemes that can properly manage the interference must be deployed in practical systems to allow the promised performance advances of 6G. Targeting these high density scenarios, we describe the Power Optimization for Low Interference and Throughput Enhancement (POLITE) paradigm for link adaptation and power allocation, which leverages available radio resources to stabilize and reduce the interference. The baseline link adaptation schemes are compared with POLITE in their performance in a 3rd generation partnership project (3GPP) calibrated system level simulator for industrial scenarios. As services in industrial environments require high reliability under constrained delays, we propose different delay-aware formulations in the POLITE design. In this work, we provide solutions both for relaxed delay requirements and for latency critical traffic, whose delay must be minimized. In particular, in the latter case, we propose also modifications of user selection and resource allocation procedures to further improve the reliability and latency. Simulation results prove the benefits of POLITE in terms of increased throughput, fulfillment of relaxed and delay-critical requirements, with an overall reduced transmit power compared to the current baseline link adaptation schemes.

COMPARISON OF WIRELESS ADAPTERS INTERFERENCE BASED ON DIFFERENCES OF FLOOR POSITION

The wireless network adapter has now been widely developed. The wireless adapter receives signal strength has several levels. It depends on the signal strength of the device with respect to the wireless signal and access point. The external adapter is used by computers that are not equipped with a wireless network adapter. Usually, internet users use a USB wireless adapter. An external adapter can also amplify signal reception from hotspots. The problem is how users consider using an external wireless adapter or just an onboard wireless adapter when there are many networks interfering with the weak signal strength of the access point. The method is implemented by measuring the value of the Received Signal Strength Indicator (RSSI). The purpose of this study is to compare the received signal strength in conditions where the signal before interference and after experiencing interference (interference). Meanwhile, the measured RSSI value is divided into four floors and with different distances for each floor. Each floor is measured by five distances. The average value of signal strength at a distance of 10 meters is -74 dBm using the onboard wireless adapter and -69 dBm using a USB wireless adapter. The value obtained after the interference is -75 dBm and the USB wireless adapter gets -61 dBm. The reduction of the RSSI value between interference and non-interference is 3%. The onboard wireless adapter is affected by interference while the external wireless adapter is not affected.

Balanced clustering approach with energy prediction and round-time adaptation in wireless sensor networks

This paper proposes three techniques to improve the energy efficiency of clustering protocols in wireless sensor networks (WSNs). The first technique reduces the periodic network re-clustering, the second adapts the rounds' durations to the cluster-heads' (CHs) residual energy, while the third one ensures fair and spatially balanced distribution of CHs over the network. For the purpose of performance evaluation, these techniques are implemented on TPSO-CR, one of the state-of-the-art clustering protocols. TPSO-CR, its enhanced version with the proposed techniques (ETPSO-CR) and LEACH-C are compared. The results demonstrate that the proposed solutions remarkably reduce and balance the total energy consumed in the network. Thereby, the time to the first node death is more than doubled in some scenarios. The improvements are ranging from 25% to 76% for several network lifetime metrics and the total number of received data at the base station is increased by 30%, on average.

Buffer Data-Driven Adaptation of Mobile Video Streaming Over Heterogeneous Wireless Networks

The development of the Internet of Things (IoT), cyber physical systems, and ubiquitous mobile terminals enable video content to be shared and consumed in new and innovative ways. Nonetheless, the stochastic and unpredictable nature of heterogeneous wireless networks with mobile clients presents a significant challenge to the increasing demand of quality of experience (QoE). In this paper, we study the problem of maximizing the user’s QoE of viewing streaming video via automatic bitrate adaptation in heterogeneous wireless networks. To be specific, a stochastic optimization problem is first formulated by considering fundamental uncertainties of heterogeneous wireless networks (i.e., the stochastic throughput). A dynamic bitrate adaptation scheme is then designed based on the Lyapunov optimization framework. Our proposed scheme conducts video bitrate selection based on the current queue buffer state and real-time throughput, and is capable of balancing the tradeoff between a user’s QoE and buffer occupation (i.e., memory utilization). The performance of our proposed scheme is investigated through a combination of extensive analysis, simulations, and experiments in a real-world testbed. Simulation results demonstrate that our scheme outperforms the baseline with regard to QoE and bandwidth utilization. In addition, the experimental results in real-world testbed validate the scheme’s efficiency and practicality in real-world system.

Similarity based image selection with frame rate adaptation and local event detection in wireless video sensor networks

Wireless Video Sensor Networks (WVSNs7unding environmental information. Those sensor nodes can locally process the information and then wirelessly transmit it to the coordinator and to the sink to be further processed. As a consequence, more abundant video and image data are collected. In such densely deployed networks, the problem of data redundancy arises when information are gathered from neighboring nodes. To overcome this problem, one important enabling technology for WVSN is data aggregation, which is essential to be cost-efficient. In this paper, we propose a new approach for data aggregation in WVSN based on images and shot similarity functions. It is deployed on two levels: the video-sensor node level and the coordinator level. At the sensor node level the proposed algorithms aim at reducing the number of frames sensed by the sensor nodes and sent to the coordinator. At the coordinator level, after receiving shots from different neighbouring sensor nodes, the similarity between these shots is computed to eliminate redundancies and to only send the frames which meet a certain condition to the sink. The similarity between shots is evaluated based on their color, edge and motion information. We evaluate our approach on a live scenario and compare the results with another approach from the literature in terms of data reduction and energy consumption. The results show that the two approaches have a significant data reduction to reduce the energy consumption, thus our approach tends to overcome the other one in terms of reducing the energy consumption related to the sensing process, and to the transmitting process while guaranteeing the detection of all the critical events at the node and the coordinator levels.

New Multifunctional Industrial Wireless Network Adapter

Abstract: Design has realized a new multifunctional industrial wireless network adapter. The purpose of this design is to avoid the isolated information island in an industrial system, and allow devices with different types of communication protocol to form one industrial network. It has realized by hardware and software. On the hardware side, the device is composed of MCU, power supply module, two rs232 communication modules, one rs485 communication module, two ethernet communication modules and the watchdog. On the software side, the adapter integrates the protocols of Modbus TCP, Modbus RTU, rs232 transparent transmission, rs485 transparent transmission, TCP server transparent transmission, TCP client transparent transmission and UDP transparent transmission. Because the device has realized the calibration algorithm, it can control rs232-HART protocol converter to achieve interconnection of the HART equipment. One of the rs232 port is used to interconnection of a wireless communication module. The wireless communication module is designed by ourselves, the wireless modules can automatically form a network of each other and communication with the host. Now the multifunctional industrial wireless network adapter has been tested and verified that it can make multiple equipments with different communication protocols form one network and works steadily.

A New Computer-based Ferromagnetic Metal Detector for Security Applications

The need for detecting and locating concealed metallic objects and contraband items increases in importance as the issues of security becomes of great concern. In the field of metal detectors, the research is being geared towards the production of detectors with fast settling times and high discriminating ability. This paper proposes a method for designing a computer-based ferromagnetic metal detector which can be employed for security applications. The LabVIEW software has been used to program the detector. It is a novel programming language from National Instruments that is robust, highly parallel and eliminates most of syntactical details associated with text based programming languages. Because of this, the development time of the detector is reduced by a significant factor. A recognition algorithm has also been designed to discriminate between ferromagnetic items by their mass and size. To improve the settling time of the detector, components with fast response times have been chosen, making the detector’s settling time to be approximately 1.1 sec. In addition, the screening process has been made more convenient by connecting the detector to a remote computer through data socket networking. The remote computer enables the detector to be monitored remotely in real time and also acts as a central database where the screening information is sent for further storage. The system hardware comprises of ten fluxgate magnetic field sensors (FLC 100) with response time of 1sec and sensitivity of 1V/50μT, a wooden frame in form of a portal, connecting cables, USB DAQ 2833, USB video camera, wireless network adapter and two laptop computers.

Exploiting Error Estimating Codes for Packet Length Adaptation in Low-Power Wireless Networks

We propose Plena, a packet length adaptation scheme exploiting recently proposed error estimating codes (EEC) for low-power wireless networks. We carefully consider two low-power MAC protocols in modeling the energy consumption of different packet lengths. Based on the modeling and analysis, we give closed form solutions for the optimal packet length in terms of energy efficiency. EEC allows for instant estimation of the bit error rate (BER) in a partially correct packet, making it possible for predicting packet reception ratios (PRRs) at different packet lengths without the need of direct measurement in an iterative process. Fast convergence of Plena makes it suitable for mobile environments in which the channel characteristics are frequently changing. We evaluate Plena’s computation overhead based on the commonly used TelosB nodes. Results show that the computation overhead of Plena is acceptably small. We also perform extensive simulations and testbed experiments to study the performance of Plena under different configurations. Results show that Plena achieves better energy efficiency than existing works.

Energy harvesting aware topology control with power adaptation in wireless sensor networks

In the recent years, energy harvesting technology has been integrated into wireless sensor networks for resolving the energy “bottleneck” problems caused by the limited-capacity batteries equipped in traditional sensor nodes. However, due to the limited capacity of energy buffers equipped for storing the harvested energy, excessive harvested energy is indiscreetly discarded while sensor nodes are staying at the status of energy saturation. To address this issue, we present a topology control approach, for the energy harvesting wireless sensor network, that allows each node to adaptively adjust its transmission power for utilizing the harvested energy effectively. Specifically, we first model the behaviors of sensor nodes as an ordinal potential game where the high harvesting power nodes cooperate with the low harvesting power nodes to maintain the connectivity of the whole network. And we theoretically prove the existence of a Nash equilibrium for the game. Then, a polynomial-time algorithm is proposed to achieve the Nash equilibrium. Simulation results show that our proposed scheme improves the energy availability and outperforms existing energy-aware schemes in terms of energy conservation and balanced distribution.

OFDMA-Based Channel-Width Adaptation in Wireless Mesh Networks

Channel-width adaptation can optimize multiple performance metrics of a wireless communication link, including transmission rate, communication range, resilience to delay spread, and power consumption. Supporting variable channel width has been considered one of the most critical features of a communication radio. How to leverage a channel-width adaptive radio to improve throughput of a wireless network is a challenging problem in the medium access control (MAC) layer. So far, there exist research results on either theoretical analysis or protocol implementation for a point-to-multipoint (PMP) infrastructure network. However, the impact of channel width to a multihop wireless network has not been fully investigated yet. More specifically, how to exploit variable channel width to enhance throughput of a multihop wireless network remains an unresolved research issue. This paper addresses this issue in wireless mesh networks (WMNs) considering orthogonal frequency-division multiple-access (OFDMA)-based channel-width adaptation. Theoretical analysis is first carried out to identify appropriate algorithms for channel width adaptation. To this end, resource allocation with OFDMA-based channel-width adaptation is formulated as an optimization problem, which is proved to be NP-complete. To reduce the computational complexity, a greedy algorithm is derived to obtain a suboptimal solution. Based on such a greedy algorithm, a distributed MAC protocol is designed for channel-width adaptation for OFDMA-based WMNs. It takes advantage of variable channel width in different time slots to achieve highly efficient resource allocation. Simulation results illustrate that the distributed MAC protocol significantly outperforms MAC protocols based on traditional channel-width adaptation.

The queuing delay analysis at relay node based on cooperative GBN-ARQ protocols

In this paper, a single relay cooperative diversity network model is proposed, analyzing queuing delay of the packets at relay node. Using dynamic radio link adaptation in wireless networks, based on the character of GBN-ARQ protocol and the queuing theory, the paper solves the problem that packets wait to transmit at relay, and presents a relay node to destination node queuing analysis model for GBN-ARQ protocol with fixed feedback delay. The paper establishes Markov model of packet transmission, and the delay statistics at relay node are figured out by using matrix geometric methods.

Toward Fuzzy Traffic Adaptation Solution in Wireless Mesh Networks

Wireless technologies are becoming an essential part of our daily life. These technologies are expected to provide a wide variety of real-time applications; hence, there is a vital need to provide quality-of-Service (QoS) support. One of the key mechanisms to support QoS is traffic regulation. The basic idea behind traffic regulation is to measure the network state (e.g., load) in order to adapt the rate of carefully selected application flows. In this paper, we propose a novel model, called FuzzyWMN, which can be used to implement traffic adaptation in Wireless Mesh Networks (WMNs).The objective of FuzzyWMN is to compute the rate adaptation to apply to application flows according to the current network state; it relies on two parameters to meet this objective: (1) packet delays between sources and destinations; and (2) buffer occupancy of network nodes. The proposed model combines the essential notions of both fuzzy logic theory and Petri nets; this enables FuzzyWMN to realize traffic adaptation in networks characterized by information uncertainty and imprecision due to the dynamic traffic behavior, channel interferences, etc. Extensive simulations show that FuzzyWMN achieves stable end-to-end delay and good throughput under different network conditions.

Routing Failure Recovery with Contention Window Adaptation in Wireless Networks

Routing Failure Recovery with Contention Window Adaptation in Wireless Networks

Queue management based duty cycle control for end-to-end delay guarantees in wireless sensor networks

In this paper, we propose an analytical method for duty cycle adaptation in wireless sensor networks so that delay requirement is guaranteed while power consumption is minimized. The proposed method, named Dual-QCon, provides a formal method for stabilizing controller design based on queue management in order to control both duty cycle and queue threshold according to changing network conditions. Dual-QCon also provides a delay notification mechanism in order to determine an appropriate queue threshold of each node according to the application-dependent and time-varying delay requirements. Based on control theory, we analyze the adaptive behavior of the proposed method and derive conditions for system stability. Asymptotic analysis shows that Dual-QCon guarantees end-to-end delay requirement by controlling parameters of local nodes. Simulation results indicate that Dual-QCon outperforms existing scheduling protocols in terms of delay and power consumption.

An integrated routing and rate adaptation framework for multi-rate multi-hop wireless networks

In this paper, we propose a new integrated framework for joint routing and rate adaptation in multi-rate multi-hop wireless networks. Unlike many previous efforts, our framework considers several factors that affect end-to-end performance. Among these factors, the framework takes into account the effect of the relative positions of the links on a path when choosing the rates of operation and the importance of avoiding congested areas. The key element of our framework is a new comprehensive path metric that we call ETM (for expected transmission cost in multi-rate wireless networks). We analytically derive the ETM metric. We show that the ETM metric can be used to determine the best end-to-end path with a greedy routing approach. We also show that the metric can be used to dynamically select the best transmission rate for each link on the path via a dynamic programming approach. We implement the ETM-framework on an indoor wireless mesh network and compare its performance with that of frameworks based on the popular ETT and the recently proposed ETOP metrics. Our experiments demonstrate that the ETM-framework can yield throughput improvements of up to 253 and 368 % as compared with the ETT and ETOP frameworks.

A Joint Approach to Routing Metrics and Rate Adaptation in Wireless Mesh Networks

This paper presents MARA, a joint mechanism for automatic rate selection and route quality evaluation in wireless mesh networks. This mechanism targets at avoiding the problems of lack of synchronization between metric and rate selection decisions and inaccurate link quality estimates, common to main existing proposals of multihop wireless routing metrics and automatic rate adaptation. In this proposal, the statistics collected by the routing protocol are used by the rate adaptation algorithm to compute the best rate for each wireless link. This coordinated decision aims at providing better routing and rate choices. In addition to the basic MARA algorithm, two variations are proposed: MARA-P and MARA-RP. The first considers the size of each packet in the transmission rate decision. The second variation considers the packet size also for the routing choices. For evaluation purposes, experiments were conducted on both real and simulated environments. In these experiments, MARA was compared to a number of rate adaptation algorithms and routing metrics. Results from both environments indicate that MARA may lead to an overall network performance improvement.

MAC Protocol Switching: A Novel Tool for Performance Adaptation in Wireless Networks

This paper presents a distributed MAC protocol switching mechanism for maximizing network throughput in the presence of traffic and topology heterogeneity. The key idea behind dynamic MAC switching is for each node to use its local topology and traffic density information to decide the most suitable MAC protocol that can maximize the MAC layer throughout in the neighborhood. A formal MAC switching rule is developed using analytical formulation of the MAC throughput available in the literature. NS2 based simulation experiments demonstrate that with the proposed MAC switching strategy, nodes in a wireless sensor network are able to achieve maximum MAC throughput by adaptively choosing the appropriate MAC protocol in the presence of heterogeneity in terms of data rate and node population.

Link Adaptation with Position/Motion Information in Vehicle-to-Vehicle Networks

Wireless communication networks use link adaptation to select physical layer parameters that optimize the transmission strategy as a function of the wireless channel realization. In the vehicle-to-vehicle (V2V) networks considered in this letter, the short coherence time of the wireless channel makes link adaptation based on the impulse response challenging. Consequently, link adaptation in V2V wireless networks may instead exploit the large-scale characteristics of the wireless channel (i.e. path loss) since they evolve slowly and enable less frequent feedback. Large-scale channel information may be captured through channel or position/motion measurements. We show, through the definition of new large-scale coherence expressions, that channel measurements render large-scale coherence as a function of time-change while the position/motion measurements render coherence as a function of velocity-change. This letter is concluded with highway simulations of modeled and measured channels to demonstrate the advantage of position/motion information for feedback reduction in V2V link adaptation.

Concerted Routing Metrics Evaluating and Distributed Rate Adaptation in Wireless Mesh Networks

Concerted Routing Metrics Evaluating and Distributed Rate Adaptation in Wireless Mesh Networks