Data Rate Communication Research Articles

Wireless powered D2D communications underlying cellular networks: design and performance of the extended coverage

ABSTRACTBecause of the short battery life of user equipments (UEs), and the requirements for better quality of service have been more demanding, energy efficiency (EE) has emerged to be important in device-to-device (D2D) communications. In this paper, we consider a scenario, in which D2D UEs in a half-duplex decode-and-forward cognitive D2D communication underlying a traditional cellular network harvest energy and communicate with each other by using the spectrum allocated by the base station (BS). In order to develop a practical design, we achieve the optimal time switching (TS) ratio for energy harvesting. Besides that, we derive closed-form expressions for outage probability, sum-bit error rate, average EE and instantaneous rate by considering the scenario when installing the BS near UEs or far from the UEs. Two communication types are enabled by TS-based protocol. Our numerical and simulation results prove that the data rate of the D2D communication can be significantly enhanced.

Sampled‐data‐based consensus of continuous‐time systems with limited data rate

Leader-following consensus is investigated for second-order continuous-time multi-agent systems with limited communication data rate in this study. The network communication topology is directed and static. Using the sampled position and velocity data, a corresponding discrete-time system, whose leader-following consensus is proved to be equivalent to that of the original system, is given. A distributed protocol is proposed based on dynamic encoding and decoding. A necessary and sufficient condition is given for the existence of such communication and control protocol to ensure the achievement of leader-following consensus, if the upper bound of the communication data rate is predetermined. Two algorithms are also presented to achieve the leader-following consensus if the communication data rate is unfixed or limited, respectively. Finally, simulation examples are given to verify and illustrate the theoretical analysis.

A 0.3-V 1- $\mu \text{W}$ Super-Regenerative Ultrasound Wake-Up Receiver With Power Scalability

This brief presents an ultralow-power wake-up receiver using ultrasound for Internet of Things applications. To achieve both high sensitivity and low power consumption, we propose a Colpitts-oscillator-based super-regenerative receiver (COSR). Owing to the simple architecture of the proposed COSR, a lowest supply voltage operation of 0.3 V and a smallest area are achieved. Furthermore, the power consumption of the proposed wake-up receiver is scalable and is determined by the input signal sensitivity and data rate, which are configurable by the user. In a field test, the proposed wake-up receiver consumes $1~\mu \text{W}$ , which is smaller by 77% than that of a conventional ultrasound wake-up receiver at a comparable communication distance and data rate.

Quality driven modulation rate optimization for energy efficient wireless video relays

Modern mobile computing devices such as smart phones have become the major user-centric video data sources in future 5G wireless networks. However, battery energy efficiency becomes the critical bottleneck for such uplink multimedia contributors. In this paper we propose a new approach to reduce energy consumption while improving Quality of Experience (QoE), by innovatively investigating video encoding frame prioritization, mode, dependency, and rate control overheads, based on communication model of a transmitter device to an access-point via a relay device. In the proposed approach, we investigate various frame level encoding dependencies and different communication data rates to study their impacts on energy efficiency and QoE. We also incorporate some simple game theory concepts to determine the best compromise of energy-quality tradeoff between the transmitter and the relay. Simulation results demonstrate that cross layer exploration of encoding dependency and game theoretical rate control have significant energy saving and quality gain potentials.

A 152-GHz OOK Transmitter With 3-dBm Output Power in 65-nm CMOS

A high output power 152 GHz ON-OFF keying transmitter in 65-nm CMOS is presented. The transmitter consists of a high dc-RF efficiency push-push voltage-controlled oscillator followed by a high-speed and high-gain switched-mode power amplifier. The transmitter achieves the highest output power (3 dBm) beyond 140 GHz in silicon process, with high on-off ratio (>39 dB) and high dc-RF efficiency (3.7%). The transmitter could support 10-Gb/s data rate communication with a bit-error rate of less than 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-12</sup> .

Iterative Learning Control for Multi-Agent Systems With Finite-Leveled Sigma-Delta Quantization and Random Packet Losses

A quantized iterative learning control (QILC) for continuous-time multi-agent systems with finite-leveled sigma-delta ( $\Sigma \Delta$ ) quantization and random packet losses is first proposed in this paper. To realize the digital communication between signals and utilize limited communication bandwidth effectively, we introduce the $\Sigma \Delta$ quantizer with limited communication data rate (quantization bits) into the control field and for the design of the QILC in this paper. In addition, the packet losses are also first considered into the QILC, which makes the controller more close to the practical engineering applications. Since the nonlinearity and randomness introduced by the quantization and packet losses, a decreasing learning gain is utilized with the help of the non-smooth analysis and mathematical expectation for the analysis of convergence. Accurate tracking in the sense of expectation can be obtained based on randomly small number of quantization bits, even merely one bit of quantization information. Numerical simulations are given to show the effectiveness of the proposed protocol.

Dedicated real-time monitoring system for health care using ZigBee.

Real-time monitoring systems (RTMSs) have drawn considerable attentions in the last decade. Several commercial versions of RTMS for patient monitoring are available which are used by health care professionals. Though they are working satisfactorily on various communication protocols, their range, power consumption, data rate and cost are really bothered. In this study, the authors present an efficient embedded system based wireless health care monitoring system using ZigBee. Their system has a capability to transmit the data between two embedded systems through two transceivers over a long range. In this, wireless transmission has been applied through two categories. The first part which contains Arduino with ZigBee will send the signals to the second device, which contains Raspberry with ZigBee. The second device will measure the patient data and send it to the first device through ZigBee transceiver. The designed system is demonstrated on volunteers to measure the body temperature which is clinically important to monitor and diagnose for fever in the patients.

High Temperature Quadrature Amplitude Modulation over Orthogonal Frequency Division Multiplexing

As downhole tools advance, they require increasingly higher data rates in communication with the surface. Current data rates over HT single-conductor wireline are limited to approximately 200 kbps. Long cables and harsh environments create a limiting challenge to standard serial bit rates due to high cable impedance and component availability. Keying techniques are often used to improve the robustness and speed of data links over long cables. Frequency shift keying (FSK) is a common implementation where data is encoded by specific frequencies on the data line. Amplitude shift keying (ASK) and phase shift keying (PSK) work on similar principles. In this project we apply quadrature amplitude modulation (QAM), a combination of PSK and ASK, and carry it over multiple frequency channels simultaneously using orthogonal frequency division multiplexing (OFDM). QAM over OFDM is a digital communications technique similar to those used in the telecommunications industry for digital subscriber line (DSL) connections and cellular networks. Using our data link, laboratory tests have demonstrated data rates of up to 3.8 Mbps over a 5000 ft (1524 m) single conductor wireline cable with less than 1e-8 bit error rate. Higher data rates are possible if error mitigation and correction coding is used. Gray encoding is an error mitigation technique where nearby points on the QAM constellation are similar in value so the errors are off only by least significant bits. A prototype point to point link protocol was developed in which the cable bandwidth is assessed empirically to optimize the OFDM by allowing for correction of cable distortion at each frequency independently. The protocol can enable use of the developed data link for a variety of tools with little to no changes by hiding all the complexity from the tool. Future versions of the protocol will automatically detect and correct transmission errors, allow for data buffering/retransmission and provide feedback as to the quality of the link. However, this new approach to the problem requires more complex computation to encode the data and signal generation electronics to produce the required waveform. One of the key challenges to full implementation of this concept on high temperature electronics is that a downhole fast Fourier transform (FFT) is required to decode the QAM information for downlink and an inverse FFT (IFFT) is required to efficiently encode data for uplink. The IFFT allows combination of multiple QAM data streams into a time series which can be converted to analog waveforms. High temperature testing of FFT and IFFT performance on the RelChip RC10001 microcontroller is included here. Also included here are the details of development of a high temperature digital to analog converter (DAC) to create composite signals and a high temperature line driver to boost analog signal transmission. This paper describes the communication architecture, the systems developed for high temperature implementation, and evaluations/implementations on high temperature computation devices.

Design of 4:8 MIMO OFDM with MSE Equalizer for Different Modulation Techniques

MIMO OFDM is one of the most promising techniques to increase the capacity and data rate in mobile communication. In this work MIMO-OFDM is designed by using 4:8 antenna and OSTBC encoder and combiner for different modulation techniques like BPSK, QPSK, QAM-16, QAM-64, QAM-256 and MSE equalizer is also used which further reduce the inter-symbol interference specially for high order modulation techniques and enhanced the performance of OFDM system. Simulation is performed to analyze the performance of different modulation technique on the basis of BER, SNR, MSE plot, constellation plot etc. It is also found that for OFDM, the BER of QPSK is 0 and QAM-16, QAM-64 and QAM-256 have almost same BER but reduction in ISI also achieved.

Characterization of Impulse Radio Intrabody Communication System for Wireless Body Area Networks

Intrabody communication (IBC) is a promising data communication technique for body area networks. This short-distance communication approach uses human body tissue as the medium of signal propagation. IBC is defined as one of the physical layers for the new IEEE 802.15.6 or wireless body area network (WBAN) standard, which can provide a suitable data rate for real-time physiological data communication while consuming lower power compared to that of radio-frequency protocols such as Bluetooth. In this paper, impulse radio (IR) IBC (IR-IBC) is examined using a field-programmable gate array (FPGA) implementation of an IBC system. A carrier-free pulse position modulation (PPM) scheme is implemented using an IBC transmitter in an FPGA board. PPM is a modulation technique that uses time-based pulse characteristics to encode data based on IR concepts. The transmission performance of the scheme was evaluated through signal propagation measurements of the human arm using 4- and 8-PPM transmitters, respectively. 4 or 8 is the number of symbols during modulations. It was found that the received signal-to-noise ratio (SNR) decreases approximately 8.0 dB for a range of arm distances (5–50 cm) between the transmitter and receiver electrodes with constant noise power and various signal amplitudes. The SNR for the 4-PPM scheme is approximately 2 dB higher than that for the 8-PPM one. In addition, the bit error rate (BER) is theoretically analyzed for the human body channel with additive white Gaussian noise. The 4- and 8-PPM IBC systems have average BER values of 10−5 and 10−10, respectively. The results indicate the superiority of the 8-PPM scheme compared to the 4-PPM one when implementing the IBC system. The performance evaluation of the proposed IBC system will improve further IBC transceiver design.

Practical Design and Implementation of Metamaterial-Enhanced Magnetic Induction Communication

Although wireless communications in complex environments, such as underground, underwater, and indoor, can enable a large number of novel applications, their performances are constrained by lossy media and complicated structures. Magnetic Induction (MI) has been proved to be an efficient solution to achieve reliable communication in such environments. However, due to the small coil antenna's physical limitation, MI's communication range is still very limited if devices are required to be portable. To this end, Metamaterial-enhanced Magnetic Induction (M$^2$I) communication has been proposed and the theoretical results predict that it can significantly increase the communication performance, namely, data rate and communication range. Nevertheless, currently, the real implementation of M$^2$I is still a challenge and there is no guideline on design and fabrication of spherical metamaterials. In this paper, a practical design is proposed by leveraging a spherical coil array to realize M$^2$I. We prove that the effectively negative permeability can be achieved and there exists a resonance condition where the radiated magnetic field can be significantly amplified. The radiation and communication performances are evaluated and full-wave simulation is conducted to validate the design objectives. By using the spherical coil array-based M$^2$I, the communication range can be significantly extended, exactly as we predicted in the ideal M$^2$I model. Finally, the proposed M$^2$I antenna is implemented and tested in various environments.

Finite-Level Quantized Synchronization of Discrete-Time Linear Multiagent Systems with Switching Topologies

In this paper, the synchronization of discrete-time linear multiagent systems is studied with finite communication data rate and switching topology flows. A class of quantized-observer-based communication schemes and a class of certainty-equivalence-principle-based cooperative control laws are proposed with adaptive encoders and decoders. It is shown that if the pairs of agents' state matrices and control matrices multiplied by Laplacian eigenvalues of the weakly connected components are simultaneously stabilizable, and the communication topology flow is frequently connected, then there exist such protocols leading to synchronization exponentially fast. Furthermore, only finite bits of information exchange per step are required to guarantee the synchronization if the communication channels are frequently active. For first-order dynamics, the dwell time and the number of bits are both related to the unstable mode of agent dynamics, the number of agents, the frequency of connectivity, and the Laplacian eigenvalue ratio of the switching topology flow.

Network Codes Based on Symmetric Matrices

The key challenges of future wireless communication are improving data rate and quality of service. However, the challenges posed by having a large number of users such as power control, frequency synchronization and independently faded channels scales with the number of users. Cooperative communications is a candidate technology for high data rate and multi-user communications. In this paper, a new design of distributed network codes is introduced. These network codes are based on algebraic constructions in finite fields. Finite fields have an attractive feature of constraining transmit signal energy and is resilient to fading channels. The codes have high diversity and scale up with an arbitrary number of users. The codes are an alternative to Generalized Dynamic Network Codes without a restriction on the field size. Results are compared to theoretical evaluations and systems with similar configurations.

Quantized Leaderless and Leader-Following Consensus of High-Order Multi-Agent Systems With Limited Data Rate

Distributed consensus with limited communication data rate is an interesting and important problem and has been studied for multi-agent networks with the first order and second order integrator dynamics. However, the problem remains challenging for higher-order systems due to the complexity of consensus analysis and data rate minimization. In this paper, the leaderless and leader-following quantized consensus for a special kind of high-order systems are considered. Each agent is assumed to be controllable and observable with single input and single output, and its system matrix admits n identical eigenvalues of 1. The special case of n-th order integrator multi-agent system with only the first state variable being measurable is first investigated, and it is shown that for a fixed undirected connected network, n bits of information exchange between agents suffice to guarantee the leaderless and leader-following quantized consensus respectively with an exponential convergence rate by employing a suitable encoding-decoding scheme and perturbation analysis of matrices. The obtained results are then extended to the general case of multi-agent dynamics with n identical eigenvalues of 1 by applying the same encoding-decoding scheme and control protocol to an observer system for each agent. The final consensus value and the application to formation control are also discussed.

Containment Control of Single-Integrator Network With Limited Communication Data Rate

This technical note investigates distributed containment control for a single-integrator continuous-time multi-agent system with a limited communication data rate. Network topology is a directed communication graph. The containment control with quantized communication for each follower is designed using only its neighbour's quantized information so that all followers move into the convex hull spanned by the leaders. Necessary and sufficient criteria which guarantee achievement of containment consensus are given if the communication data rates are unfixed or fixed. Under a given bound on communication data rate, an algorithm is established to achieve the containment consensus. Finally, all the theoretical results are illustrated by numerical simulations.

Verilog Implementation of Collision Avoidance System based on FlexRay Protocol

Background/Objective: The objective of this paper is to provide an insight into the FlexRay protocol, as well as build a simple collision avoidance system based on it. FlexRay is a next generation intra-vehicular communication protocol that provides fault-tolerant, flexible, high data rate and deterministic communication between the different electronic units in an automobile, mainly used for advanced automobile control and safety-critical applications. Methods/Statistical Analysis: Here, a simple collision avoidance system for an automobile is built using Verilog HDL, where data is transmitted according to the FlexRay protocol. Separate Verilog modules are designed for an ultrasonic sensor and a motor. Data is transmitted in the FlexRay frame format. Simulation of results are tested in ModelSim tool. Findings: It is observed that under the FlexRay protocol, data is transmitted at a much greater speed. Also, there are better fault tolerance and better error detection mechanisms, all of which are quintessential for a safety-critical application like collision avoidance. It also ensures safe communication between the devices inside an automobile. Applications/Improvements: More advanced automotive applications like automatic steering, temperature regulation, etc., can be implemented in a similar manner based on the protocol. The protocol is mainly used for safety-critical applications owing to its huge cost of implementation.

Mobile-phone based visible light communication using region-grow light source tracking for unstable light source.

In order to increase the data rate of the camera-based visible light communication (VLC) system, using rolling shutter effect has been demonstrated successfully, in which the pixel rows of the complementary-metal-oxide-semiconductor (CMOS) image sensor are activated sequentially. Previous camera-based VLCs focused on using a stable LED light source, and its illumination area is positioned at the center of an image frame. In this work, we investigate the performance of a camera-based VLC with light source at different parts of an image frame. We propose and demonstrate using region-grow algorithm to track the light source. We also evaluate and discuss different scenarios when the light source is moved. Besides, a recorded > 5 kbit/s net data rate can be achieved by using only a single phosphor-based white-light LED source. Here, we demonstrate that 4.502 pixel/bit can be achieved.

Analyzing point-to-point DDS communication over desktop virtualization software

Virtualization technologies introduce additional uncertainty and overhead for distributed applications, that may challenge their timeliness. The additional software abstraction layers of the virtualization software offer powerful parallel execution environments but, at the same time, reduce the effective performance as additional software layers are introduced. This requires some fine tuning of, among others, the communication middleware software. The different resource management mechanisms of the middleware may collide with the specific algorithms replicated by the underlying virtualization software. The present work characterises the set of steps of a publish-subscribe communication middleware in a distributed system, enhancing it to suit the communication scheme of virtualized remote nodes. The potential communication steps are identified, and the overhead introduced by the execution over the virtualization software is provided by means of a data communication rate metric; a set of benchmark tests are presented that empirically evaluate the overhead and stability of the most widely used publish-subscribe (P/S) middleware named DDS (Data Distribution System for real-time systems). A general purpose cloud computing virtual machine monitor is utilized to identify the side effects and the drawbacks of the general virtualization technology. Results are obtained on a setting with two different DDS implementations over a general purpose virtualization software, together with a discussion about the potential drawbacks of the main communication operations.

Novel DSP Receiver Architecture for Multi-Channel Visible Light Communications in Automotive Applications

This paper presents a novel visible light communication receiver architecture, designed for automotive applications. A crucial problematic in this area is the design of a suitable receiver able to face the problems caused by the dynamic situations, by the long distances and also by the environmental conditions. In such circumstances, a solution would be to adapt the communication's data rate to channel conditions, meaning that the communication would take place using different data rates, depending on the signal-to-noise ratio (SNR) and the message priority. Considering the digital filtering a better performance, the proposed architecture considers the usage of digital signal processing as an alternative to the analog signal treatment. The visible light communication receiver proposed in this paper addresses the above-mentioned issues and enables a robust communication even at low SNR.

Energy Detection for MIMO Decision Fusion in Underwater Sensor Network: Critical Review

Underwater sensor network has different applications ranging from environmental monitoring, data collection to survey mission and coastal surveillance. In this paper several fundamental aspects of underwater acoustic communication are discussed in detail. Different architecture and channel model are also been discussed. This paper also covers the latest techniques which are used in order to increase the data rate in underwater acoustic communication. The performance of the energy detector which is considered for binary hypothesis decision fusion has been reviewed and analyzed on different parameters of the investigation. This paper is based on a MIMO model for underwater acoustic network using Neymen-Pearson/ Bayesian hypothesis testing. Previous investigation and the conclusion will be useful for possible future research direction. KeywordsFusion, Energy detection, Multiple-input Multiple-output (MIMO), underwater sensor networks