Wireless Design Research Articles

Effects of Radio-Transmitters on Body Condition, Harvest Rate, and Survival of Bobwhites

Numerous studies of northern bobwhite (Colinus virginianus) population and habitat ecology employ use of radio-telemetry techniques to relocate and monitor individuals. Radio-telemetry enables estimation of reproductive success, survival, movements, and home range at levels of resolution not otherwise possible. Unbiased estimation of these parameters via radio-telemetry assumes that survival, reproduction, and behavior of radio-marked individuals are not affected by carrying the radio-transmitter. These assumptions have not been rigorously tested for bobwhites. In 1993, we initiated a study at Divide Section Wildlife Management Area in Mississippi and at Tall Timbers Research Station to test the effects of radio-transmitters on survival, harvest rate, and body condition of bobwhites. From 1993 to 1996 we banded 221 and radio-marked 259 bobwhites on Tall Timbers Research Station. Harvest rate for radio-marked bobwhites was 18.5% and banded birds 12.7%. In 2 of 3 years, radio-marked birds experienced greater mean weight loss between capture and harvest than banded birds. From 1994 to 1995 we radio marked 188 and banded 210 birds on Divide Section Wildlife Management Area. Harvest rate for radio-marked birds was 40% and banded birds 30%. In the 1995-1996 hunting season radiomarked birds had lower mean weight gain from capture to harvest than banded birds. Based on our sample of marked birds, 34% of the fall population on this area was harvested. We have established a captive breeding colony of wild bobwhites at the Blackjack Captive Animal Research Facility at Mississippi State University. During the summer of 1996, genetically wild progeny are being produced to be used in a pen study to evaluate the effects of radio-transmitters on bobwhite body weight and lipid levels under abundant and scarce food resources. This study will provide the first harvest rate estimates for bobwhites on a public hunting area in Mississippi. Additionally, this study will evaluate the effects of radio-transmitters on bobwhite body condition, survival, and harvest rate. It will either validate the assumption of no radio effects and aid interpretation of previous and future radio studies or elucidate critical violations of fundamental assumptions of this methodology. If radio effects are detected, this study will identify the specific mechanisms creating bias in estimation of population parameters. This information will enable researchers to target radio design problems and develop new radio technology with reduced effects. Preliminary results suggest that radio-marking may marginally increase bobwhite vulnerability to harvest and potentially predation.

Enabling Sensor Network to Smartphone Interaction Using Software Radios

Recent advances in smartphone processing power have opened the possibilities for them to act as the processing component of software-defined radios (SDRs). For low-power sensor network systems using various communication protocols, this means that smartphones, when equipped with an SDR, can be their system management end-devices, (potentially) without the need for external communication modules. Nevertheless, the high processor and energy usage overhead of SDRs remains a major technical barrier that blocks the practical adoption of smartphone-based SDRs. In this work, we show that implementation flexibility at the software can relax this overhead. Specifically, we show, using an implementation of the low-power listening (LPL) Medium Access Control (MAC), that software improvements have the potential to significantly reduce the operational overhead of SDRs. Moreover, we show that implementing packet reception filters can help further reduce the performance overhead without sacrificing application-level message exchange qualities. Empirical results with a smartphone-based SDR suggest that by combining LPL with packet reception filters, the processing and energy overhead can be reduced by two to three orders of magnitude. We not only see this as a chance to practically realize smartphones as a wireless sensing system controller but also believe that the experiences with practical smartphone-based SDRs can provide guidelines for future wireless protocol and low-power radio designs that are suitable for mobile computing environments.

Multi-Level Pre-Correlation RFI Flagging for Real-Time Implementation on UniBoard

Because of the denser active use of the spectrum, and because of radio telescopes higher sensitivity, radio frequency interference (RFI) mitigation has become a sensitive topic for current and future radio telescope designs. Even if quite sophisticated approaches have been proposed in the recent years, the majority of RFI mitigation operational procedures are based on post-correlation corrupted data flagging. Moreover, given the huge amount of data delivered by current and next generation radio telescopes, all these RFI detection procedures have to be at least automatic and, if possible, real-time. In this paper, the implementation of a real-time pre-correlation RFI detection and flagging procedure into generic high-performance computing platforms based on field programmable gate arrays (FPGA) is described, simulated and tested. One of these boards, UniBoard, developed under a Joint Research Activity in the RadioNet FP7 European programme is based on eight FPGAs interconnected by a high speed transceiver mesh. It provides up to 4 TMACs with ®Altera Stratix IV FPGA and 160 Gbps data rate for the input data stream. The proposed concept is to continuously monitor the data quality at different stages in the digital preprocessing pipeline between the antennas and the correlator, at the station level and the core level. In this way, the detectors are applied at stages where different time–frequency resolutions can be achieved and where the interference-to-noise ratio (INR) is maximum right before any dilution of RFI characteristics by subsequent channelizations or signal recombinations. The detection decisions could be linked to a RFI statistics database or could be attached to the data for later stage flagging. Considering the high in–out data rate in the pre-correlation stages, only real-time and go-through detectors (i.e. no iterative processing) can be implemented. In this paper, a real-time and adaptive detection scheme is described. An ongoing case study has been set up with the Electronic Multi-Beam Radio Astronomy Concept (EMBRACE) radio telescope facility at Nançay Observatory. The objective is to evaluate the performances of this concept in term of hardware complexity, detection efficiency and additional RFI metadata rate cost. The UniBoard implementation scheme is described.

4-GNSS radio occultation satellite constellation design based on Dual-gate uniformity evaluation index

A brand-new area of low earth orbit satellite constellation research has been expanded by global navigation satellite system (GNSS) radio occultation (RO) atmosphere sounding technology in the last decade. The possibility of reducing the sounding satellites while keeping the amount of atmosphere soundings increasing to produce low-cost meteorological data product is investigated, and a constellation capable of receiving the RO signals from all the 4-GNSS, such as GPS, GLONASS, Galileo, and Compass, is proposed in this paper. This paper focuses on the mathematical problems on the design of 4-GNSS RO satellite constellation. A forward GNSS RO sounding simulation algorithm based on ideal atmosphere model and two-dimensional radial tracing algorithm is presented for a rapidly and accurately sounding performance prediction of 4-GNSS RO satellite constellations. Then, an improved uniformity evaluation factor named Dual-gate is established for 4-GNSS RO satellite constellation optimization design, which is a combination of the uniformity evaluation factors for the latitudinal distribution of RO soundings and those for the gridding uniformity. On the basis of low earth orbit satellite orbit dynamics and spherical geometry, the impacts of partial constellation parameters on the amount and coverage performance accorded with Dual-gate uniformity evaluation index are derived, and a series of design criteria of 4-GNSS RO satellite constellation are summarized. A simplified 4-GNSS RO satellite constellation model is built on the basis of the design criteria, and an improved ant colony algorithm is used to optimize the parameters of a 4-GNSS RO constellation including as many satellites as COSMIC-2. The simulation result shows that this 4-GNSS RO constellation is capable of obtaining near 3000 atmosphere soundings per 3 h. It obtains 13% more soundings than COSMIC-2 with the same 4-GNSS RO sounding devices, and the uniformity of soundings is increased by 9%.

A Scalable and Flexible Radio Access Network Architecture for Fifth Generation Mobile Networks

The fifth generation of mobile networks is expected to become the key enabling technology for new services and businesses in the Internet of Things realm, including automotive and industry communications. At the same time, the demand for the “bread and butter” services of mobile broadband will continue to increase, driving the need for ubiquitous data capacity everywhere. Compared to 3GPP LTE, fifth generation radio access networks need to support much more diverse requirements with a wide range of deployment options for infrastructure and spectrum availability. Based on this insight, this article discusses a flexible and scalable radio access network architecture design.

"Intelligent" Software-Defined Radio ( [Book/Software Reviews

The book reviewed is, Cognitive Radio: Interoperability through Waveform Reconfiguration (Lechowicz, L. and Kokar, M.M.; 2015) contains ten chapters and three appendices. Cognitive radio, which combines a software-defined radio (SDR) with an intelligent agent, promises to deliver a new level of functionality. The two authors started this study while in graduate school and continued through their doctoral research. Chapter 1 opens the text by describing the interoperability of communicating systems, with a focus on the physical layer of the protocol stack of dynamic interoperability, in which the rules that define the replies to particular types of messages are introduced during the system’s operation. Also addresses some of the following topics: fundamentals of sampling and digital signal processing; software defined radio; cognitive radio; interoperability and reconfiguration; AND ontology-based cognitive radio reconfiguration. The final chapter includes a summary of the main intent of the book: reconfiguration of waveforms on the fly, which also applies to emergency response cases. This book adeptly gathers all the research and development work done in the past few years and paves the way for future research. For radio engineers who wish to pursue cognitive radio design or research, this book can serve as a guiding resource.

An RFID-based tracking system for denim production processes

Since radio frequency identification technology usage is increasing, applications in this area have a rising trend day by day. However, successful studies related to radio frequency identification implementation, which combine many different areas, are not sufficient enough. Studies have mostly emphasized theoretical approaches rather than being practical studies. In this study, a roadmap for radio frequency identification design, configuration and deployment is presented in order to design an integrated approach as pointed out in the literature and in former radio frequency identification projects. Additionally, an application is performed for validation and reinforcing of the understanding of the proposed radio frequency identification implementation roadmap; an architectural framework and economic feasibility are also discussed. The most striking result from the case study is that a radio frequency identification application could be successfully implemented to support the tracking and tracing of work in process in denim production processes, an area in which studies about radio frequency identification applications have not been done. Besides this, redundant inventory and production costs, redundant labour costs caused by inefficient production activities, inaccuracies of records, incorrect order deliveries and penalty costs incurred by customers are significantly reduced, which provides invaluable advantages in the real-life competition of the denim product industry.

Efficient signal detection for cognitive radio relay networks under imperfect channel estimation

AbstractAssuming imperfect channel knowledge at the destination, we propose an improved detector for an underlay cognitive (secondary) amplify‐and‐forward wireless relay network coexisting with a primary transmission system. At first, we adjust the amplify‐and‐forward relay amplification factors by taking into account the interference temperature constraint at the primary receiver. In a second step, for the case of coherent distributed space‐time coding at the relays and maximum a posteriori signal detection at the destination, we propose a modified detector formulation. The proposed scheme reduces the impact of channel uncertainty on the receiver performance by appropriately exploiting the statistics of the channel estimation errors. Furthermore, it takes into account the interference level limitation imposed by the primary transmission system on the relays. Through some numerical results, we show that the proposed detector reduces significantly the required power level to achieve a target performance at the destination, which is of special interest for underlay cognitive radio systems. This way, the proposed receiver allows a reduction of the required protection area around the primary transmitter, leading to the increased of flexibility of the cognitive radio network design. Copyright © 2016 John Wiley & Sons, Ltd.

A Multimode SiGe BiCMOS 5–6 GHz Front-End IC that Enables 802.11ac Wave 2 and 802.11ax Wireless LAN Front-End Designs

A multimode 4.9–5.9 GHz ultra-linear single chip front-end integrated circuit (FEIC) for 802.11ac and emerging multi-gigabit per second (Gbps) wireless local area network (WLAN) applications is presented. The design is based on SiGe BiCMOS and realized in a 2.0 x 2.0 x 0.5 mm3 package. The FEIC design consists of both transmit (Tx) and receive (Rx) chains, which integrates a single-pole double-throw (SPDT) Tx/Rx CMOS switch, a SiGe power amplifier (PA), and a SiGe low noise amplifier (LNA) with a CMOS bypass attenuator. The SiGe PA in the transmit chain integrates input and output matching networks, harmonic filters, out-of-band rejection filters, supply voltage regulator and multi-mode bias circuits, temperature and voltage compensated power detector with on-chip directional coupler, and CMOS-compatible enable circuitry. The PA is controlled by the on-chip temperature and voltage compensated bias controller. With a 5 V supply, the transmit chain features 31 dB gain and excellent linearity. The transmit chain can deliver 19 dBm output power with current consumption 220 mA meeting below -40 dB Dynamic Mode Error Vector Magnitude (DEVM) for 1024 QAM signals and 20 dBm with current consumption 250 mA meeting below -35 dB DEVM for 256 QAM signals. The feature of ultra-low DEVM enables the emerging 1024-QAM applications. The harmonics emissions of the transmit chain can achieve below -50 dBm/MHz, greatly exceeding FCC out-of-band emission requirements. In addition, the linearity of the transmit chain output power is well scaled with the supply voltage from 3.0 V to 5.5V and insensitive to signal modulation bandwidths as well as duty cycles. The low linearity mode features 50 mA lower current consumption comparing to the high linearity mode. With the use of digital pre-distortion (DPD), it can achieve the similar linear power with 50 mA current reduction. The integrated log detector with an on-chip directional coupler ensures the accurate power control over 24 dB with less than 0.5 dB power control inaccuracy under VSWR 3:1 mismatch, which significantly increases the dynamic range and accurate power control for the transmit path. The Rx chain features noise figure (NF) below 2.5 dB with 15 dB gain and the current consumption of 8 mA as well as 8 dBm IIP3. The receive chain also integrates an 8 dB bypass attenuator having 25 dBm IIP3 with 3uA current consumption, which can prevent the WLAN radio from saturation under high field strength illuminations. All these unique features provide a turn-key solution for the single band or dual-band 802.11ac radio front-end circuits and emerging multiple gigabits per second high linearity WLAN radio designs. Figure 1

Numerical and Analytical Investigations of Nonlinear Synthesis Problems of Antenna with the Flat Radiating Aperture

The review article contains results of researches of the synthesis problems of radiating systems with incomplete input information arising in particular during optimal design of radio, acoustic or other types of radiating systems (RS) by the given requirements to energy characteristics of radiated field. In mathematical terms, these tasks are reduced to study and nume­rical solution of one class of two-dimensional nonlinear integral equations of Hammerstein type that depend on two real para­meters. It was established that a characteristic feature of this class of equations is nonuniqueness and the branching (or bifur­cation) of existing solutions. Methods of solving two-parametric nonlinear spectral problem, which is necessary to finding the set of points of branching are proposed. Algorithms and numerical methods for the finding of branching solutions are built and founded. Numerous examples of specific synthesis problems are presented.

Tunable scattering cancellation cloak with plasmonic ellipsoids in the visible

The scattering cancellation technique is a powerful tool to reduce the scattered field from electrically small objects in a specific frequency window. The technique relies on covering the object of interest with a shell that scatters light into the far field of equal strength as the object, but $\pi$ out-of-phase. The resulting destructive interference prohibits its detection in measurements that probe the scattered light. Whereas at radio or microwave frequencies feasible designs have been proposed that allow to tune the operational frequency upon request, similar capabilities have not yet been explored in the visible. However, such ability is decisive to capitalize on the technique in many envisioned applications. Here, we solve the problem and study the use of small metallic nanoparticles with an ellipsoidal shape as the material from which the shell is made to build an isotropic geometry. Changing the aspect ratio of the ellipsoids allows to change the operational frequency. The basic functionality is explored with two complementary analytical approaches. Additionally, we present a powerful multiscattering algorithm that can be used to perform full wave simulations of clusters of arbitrary particles. We utilize this method to analyze the scattering of the presented designs numerically. Hereby we provide useful guidelines for the fabrication of this cloak with self-assembly methods by investigating the effects of disorder.

A Locally Optimal Soft Linear-Quadratic Scheme for CR Systems in Shadowing Environments

In this letter, we analyze the problem of detecting spectrum holes in cognitive radio systems under the Neyman–Pearson scenario. We consider that a group of unlicensed users use noncoherent energy detectors to sense the radio signal and design a soft locally optimal linear-quadratic statistic based on the deflection coefficient. Each unlicensed user transmits the processed data to a central entity, where the decision about the presence or not of licensed users is made. Using the method of Monte Carlo, we show that the proposed statistic outperforms previous ones available in the literature in a wide range of shadow-fading scenarios and it is robust against parameters errors.

Spectrum sensing in satellite cognitive radios: Blind signal detection technique

In this article, cyclostationary analysis of the communication satellite signals has been performed and a simpler spectrum sensing technique using the features in the spectral density has been devised. The proposed technique makes use of the time smoothing cyclic periodogram for estimating the spectral density of the captured signal and a normalized feature vector is calculated from the spectral density. Using the defined threshold, feature vector peaks are counted and decision of signal presence or absence is made. The proposed technique is simpler in operation as compared to other techniques, which requires high resolution analysis for feature detection, particularly pattern recognition using artificial neural networks training datasets or wavelet analysis for de-noising spectral density. The proposed technique works without any prior knowledge of the captured data. It is also found to be least affected by the location and magnitudes of the feature peaks as they appear in the spectral density due to maximum value normalization. Detection of the signals has been done without any pre-processing such as de-noising. The USRP2 platform is used to capture the real-time satellite modulated carriers of BPSK, QPSK, and 16-QAM along with the noise in the satellite spectrum using GNU Radio. Further analysis and simulations are performed in the Matlab. The next generation of satellite cognitive radio designs can use this new algorithm to quickly sense, at low resolution and with less complexity/stability in the presence of a carrier signal or noise in the satellite spectrum. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1377–1384, 2016

RF Basics [Book\/Software Reviews

The content of this book is meant to fill the gap between communication hardware circuit-level specifications and communicationsystem level design considerations. The book also provides some insight into the practical aspects of the radio front-end design process at a higher level in order to convey how circuits operate together to provide an overall working system. This includes RF systems design, introduction to communications systems, basic RF design concepts and building blocks, system-level architecture and design, frequency synthesizers, and block-level radio design examples.

Performance Analysis of AODV on the Basis of Network Survivability over MANET using NS2

In Mobile Ad-Hoc Networks (MANETs), mobile devices are equipped with power (energy). In order to utilize this energy equipped devices efficiently for transmission of data packets, many energy aware routing strategies are followed. Effective transmission power control is a critical issue in the design and performance of wireless ad hoc networks. Transmission Power affects the Survivability of the Network. Today, the design of packet radios and protocols for wireless ad hoc networks are primarily based on common-range transmission control. Mobility speed of the nodes and extension of ad hoc network affects the performance as well. In this paper, one of the widely used routing protocol AODV with varying transmission range, mobility speed and number of nodes is analyzed. Data transmitted by a node is received by all the nodes within its communication range. This paper focuses on the analysis of varying the range of the transmission in terms of distance, mobility speed and number of nodes in the network. The proposed work has been simulated using NS2.34.The performance metrics comprises of Network Survivability has been analyzed in this paper.

A technique for detection of PeV neutrinos using a phased radio array

The detection of high energy neutrinos (1015–1020 eV) is an important step toward understanding the most energetic cosmic accelerators and would enable tests of fundamental physics at energy scales that cannot easily be achieved on Earth. In this energy range, there are two expected populations of neutrinos: the astrophysical flux observed with IceCube at lower energies (∼1 PeV) and the predicted cosmogenic flux at higher energies (∼1018 eV) . Radio detector arrays such as RICE, ANITA, ARA, and ARIANNA exploit the Askaryan effect and the radio transparency of glacial ice, which together enable enormous volumes of ice to be monitored with sparse instrumentation. We describe here the design for a phased radio array that would lower the energy threshold of radio techniques to the PeV scale, allowing measurement of the astrophysical flux observed with IceCube over an extended energy range. Meaningful energy overlap with optical Cherenkov telescopes could be used for energy calibration. The phased radio array design would also provide more efficient coverage of the large effective volume required to discover cosmogenic neutrinos.

Simulative Analysis of Multi-tone RoF Transmission System

AbstractThis paper deals with the design of multi-tone Radio over Fiber (RoF) system, which could efficiently support increasing demand of new services and increasing user traffic. It analyzed electrical power at different frequencies, SNR at input power P

Spiral Slotted Microstrip Antenna Design for 700 MHz Band Application

This work describes the design and implementation of spiral slotted microstrip antenna. Recently, just like other countries, in Mexico, terrestrial digital television has been implemented (analogic shutdown); as a consequence, the 700 MHz UFH Band (698–806 MHz) has been opened to new telecommunications services, particularly wireless mobile communication. This technological advance represents a radio mobile antenna design challenge because it is necessary to design an antenna whose dimensions must be small enough, which satisfies gain, resonance frequency, and bandwidth requirements and is of low cost.

Design of OFDM-Based Radio Communication Systems for Coast-to-Sea and Coast-to-Air Propagation Environments

Abstract In the paper the study of radio communication system design process for systems based on OFDM transmission is considered. The signal propagation model for 1.4 GHz frequency band is discussed, and the study of signal propagation characteristics, important from the point of view of OFDM system design, is presented. The methodology of OFDM interface design is proposed and some characteristics of the OFDM-based radio communication system are analysed.

Beamforming for Millimeter Wave Communications: An Inclusive Survey

The remarkable growth of wireless data traffic in recent times has driven the need to explore suitable regions in the radio spectrum to meet the projected requirements. In pursuance of this, millimeter wave communications have received considerable attention in the research fraternity. Due to the high path and penetration losses at millimeter wavelengths, antenna beamforming assumes a pivotal role in establishing and maintaining a robust communication link. Beamforming for millimeter wave communications poses a multitude of diverse challenges due to the large channel bandwidth, unique channel characteristics, and hardware constraints. In this paper, we track the evolution and advancements in antenna beamforming for millimeter wave communications in the context of the distinct requirements for indoor and outdoor communication scenarios. We expand the scope of discussion by including the developments in radio frequency system design and implementation for millimeter wave beamforming. We explore the suitability of millimeter wave beamforming methods, both, existing and proposed till midyear 2015, and identify the exciting new prospects unfolding in this domain.