Innovative Communication System Research Articles

Dynamically tunable terahertz passband filter based on metamaterials integrated with a graphene middle layer**Project supported by the National Natural Science Foundation of China (Grant Nos. 61701434, 61735010, and 61675147), the Open Fund of the Key Laboratory of Optoelectronic Information Technology, Ministry of Education (Tianjin University), China, the Key Laboratory of Optoelectronic Information Functional Materials and Micro-Nano devices in Zaozhuang, China,

The dynamic tunability of a terahertz (THz) passband filter was realized by changing the Fermi energy (EF) of graphene based on the sandwiched structure of metal–graphene–metal metamaterials (MGMs). By using plane wave simulation, we demonstrated that the central frequency (f0) of the proposed filter can shift from 5.04 THz to 5.71 THz; this shift is accompanied by a 3 dB bandwidth (Δf) decrease from 1.82 THz to 0.01 THz as the EF increases from 0 to 0.75 eV. Additionally, in order to select a suitable control equation for the proposed filter, the curves of Δf and f0 under different graphene EF were fitted using five different mathematical models. The fitting results demonstrate that the DoseResp model offers accurate predictions of the change in the 3 dB bandwidth, and the Quartic model can successfully describe the variation in the center frequency of the proposed filter. Moreover, the electric field and current density analyses show that the dynamic tuning property of the proposed filter is mainly caused by the competition of two coupling effects at different graphene EF, i.e., graphene–polyimide coupling and graphene–metal coupling. This study shows that the proposed structures are promising for realizing dynamically tunable filters in innovative THz communication systems.

The APN-PLACE Telehealth Education Network: Legal and Regulatory Considerations

Telehealth technology can enhance nursing clinical education by allowing for virtual site visits, preceptor support, preceptor education, and student oversight. The Advance Practice Nurse-Preceptor Link and Clinical Education (APN-PLACE) Telehealth Education Network is a new and innovative video communication system that connects schools of nursing to preceptors and clinical practice sites. Specific areas of focus include preceptor education and support, student assessment, and clinical experiences when implementing a telehealth education network. As with in-person, or traditional, clinical education, it is important to consider the legal and regulatory issues related to the use of telehealth programs in clinical education. This article presents a telehealth preceptor support network and provides an overview of the associated legal and regulatory issues surrounding its use in advanced practice registered nurse clinical education.

Connecting Small Farmers in the Caribbean to Knowledge, Networks, and Institutions Through ICTs

ABSTRACTInformation and communication technologies (ICTs) have been shown to be useful in agricultural knowledge systems to improve communication linkages among research, extension services, and farmers. The end result would be new information and technologies being made available to those who need it the most in larger numbers and in a timelier manner. While the role of ICTs in stimulating technological, organizational, institutional, and policy innovations in developing countries has been recognized, in many Caribbean States where ICTs are becoming readily available, the development and use of ICT in agricultural research and innovation systems remain underexploited, despite the fact that the agricultural sector in these developing nations accounts for a significant amount of the total employed labor force. This article traces key developments in ICT use in the agricultural sector in the Caribbean region, while highlighting the challenges as well as the potential of this technology. Several initiatives in the region are described and suggestions made for the development of innovative, appropriate, and efficient information and communication systems.

Communication system and team situation awareness in a multiplayer real-time learning environment: application to a virtual operating room

Digital multi-player learning games are believed to represent an important step forward in risk management training, especially related to human factors, where they are trusted to improve the performance of a team of learners in reducing serious adverse events, near-misses and crashes in complex socio-technical systems. Team situation awareness is one of the critical factors that can lead the team to consider the situation with an erroneous mental representation. Then, inadequate decisions are likely to be made regarding the actual situation. This paper describes an innovative communication system designed to be used in digital learning games. The system aims at enabling the learners to share information and build a common representation of the situation to help them take appropriate actions, anticipate failures, identify, reduce or correct errors. This innovative system is neither based on voice-chat nor branching dialogues, but on the idea that pieces of information can be manipulated as tangible objects in a virtual environment. To that end, it provides a handful of graphic interactions allowing users to collect, memorize, exchange, listen and broadcast information, ask and answer questions, debate and vote. The communication system was experimented on a healthcare training context with students and their teacher. The training scenario is set in a virtual operating room and features latent critical events (wrong-patient or wrong-side surgery). Teams have to manage such a critical situation, detect anomalies hidden in the environment and share them to make the most suitable decision. Analyzing the results demonstrated the efficacy of the communication system as per the ability for the players to actually exchange information, build a common representation of the situation and make collaborative decisions accordingly. The communication system was considered user-friendly by the users and successfully exposed lifelike behaviors such as debate, conflict or irritation. More importantly, every matter or implicit disagreement was raised while playing the game and led to an argued discussion, although eventually the right decision was not always taken by the team. So, improving the gameplay should help theplayers to manage a conflict and to make them agree on the most suitable decision.

Analysis of a receiver-based reliable broadcast approach for vehicular networks

The Intelligent Transportation Systems concept provides the ground to enable a wide range of applications to improve traffic safety and efficiency. Innovative communication systems must be proposed taking into account, on the one hand, unstable characteristics of vehicular communications and, on the other hand, different requirements of applications. In this paper a reliable (geo-)broadcasting scheme for vehicular ad-hoc networks is proposed and analyzed. This receiver-based technique aims at fulfilling the received message integrity yet keeping the overhead at a reasonably low level. The results are compared to simulation studies carried out in the Network Simulator-3 (NS-3) simulation environment demonstrating good agreement with each other. The analysis shows that in a single-hop scenario, receiver-based reliable broadcasting can provide good reliability, while giving very little overhead for high number of receivers.

Graphene-Based Plasmonic Tunable Low-Pass Filters in the Terahertz Band

We propose the concept, synthesis, analysis, and design of graphene-based plasmonic tunable low-pass filters operating in the THz band. The proposed structure is composed of a graphene strip transferred onto a dielectric and a set of polysilicon DC gating pads located beneath it. This structure implements a stepped impedance low-pass filter for the propagating surface plasmons by adequately controlling the guiding properties of each strip section through graphene's field effect. A synthesis procedure is presented to design filters with desired specifications in terms of cut-off frequency, in-band performance, and rejection characteristics. The electromagnetic modeling of the structure is efficiently performed by combining an electrostatic scaling law to compute the guiding features of each strip section with a transmission line and transfer-matrix framework, approach further validated via full wave simulations. The performance of the proposed filters is evaluated in practical scenarios, taking into account the presence of the gating bias and the influence of graphene's losses. These results, together with the high miniaturization associated with plasmonic propagation, are very promising for the future use and integration of the proposed filters with other graphene and silicon-based elements in innovative THz communication systems.

Effectiveness of the P3-speller in brain-computer interfaces for amyotrophic lateral sclerosis patients: a systematic review and meta-analysis.

A quarter of century ago, Farwell and Donchin (1988) described their mental prosthesis for “talking off the top of your head.” This innovative communication system, later named P3-speller, has been the most investigated and tested brain–computer interface (BCI) system, to date. A main goal of the research on P3-spellers was the development of an effective assistive device for patients with severe motor diseases. Among these patients are those affected by amyotrophic lateral sclerosis (ALS). ALS patients have become a target population in P3-speller (and more generally in BCI) research. The P3-speller relies on the visual sensory modality, and it can be controlled by requiring users to actively move their eyes. Unfortunately, eye-movement control is usually not spared in the last stages of ALS, and, then, it is definitively lost in the case of complete paralysis. We reviewed the literature on ALS patients tested by means of P3-speller systems. Our aim was to investigate the evidence available to date of the P3-spellers effectiveness in ALS patients. To address this goal, a meta-analytic approach was adopted. The pooled classification accuracy performance, among retrieved studies, was about 74%. This estimation, however, was affected by significant heterogeneity and inconsistency among studies. This fact makes this percentage estimation (i.e., 74%) unreliable. Nowadays, the conclusion is that the initial hopes posed on P3-speller for ALS patients have not been met yet. In addition, no trials in which the P3-speller has been compared to current assistive technologies for communication (e.g., eye-trackers) are available. In conclusion, further studies are required to obtain a reliable index of P3-speller effectiveness in ALS. Furthermore, comparisons of P3-speller systems with the available assistive technologies are needed to assess the P3-speller usefulness with non-completely paralyzed ALS-patients.

FireWatch: Creative Responses to Bushfire Catastrophes

FireWatch: Creative Responses to Bushfire Catastrophes

Analysis of MIMO Systems used in planning a 4G-WiMAX Network in Ghana

With the increasing demand for mobile data services, Broadband Wireless Access (BWA) is emerging as one of the fastest growing areas within mobile communications. Innovative wireless communication systems, such as WiMAX, are expected to offer highly reliable broadband radio access in order to meet the increasing demands of emerging high speed data and multimedia services. In Ghana, deployment of WiMAX technology has recently begun. Planning these high capacity networks in the presence of multiple interferences in order to achieve the aim of enabling users enjoy cheap and reliable internet services is a critical design issue. This paper has used a deterministic approach for simulating the Bit-Error-Rate (BER) of initial MIMO antenna configurations which were considered in deploying a high capacity 4G-WiMAX network in Ghana. The radiation pattern of the antenna used in the deploying the network has been simulated with Genex-Unet and NEC and results presented. An adaptive 4x4 MIMO antenna configuration with optimally suppressed sidelobes has been suggested for future network deployment since the adaptive 2x2 MIMO antenna configuration, which was used in the initial network deployment provides poor estimates for average BER performance as compared to 4x4 antenna configuration which seem less affected in the presence of multiple interferers.

Real-time 3D video communication in 3D virtual worlds: Technical realization of a new communication concept

After a failed initial attempt in the 1950s to bring three dimensionality into the entertainment sector, 3D technologies today have reached a point where media production, transportation, as well as consumption are of sufficient speed and quality to finally advance the complete media chain from two dimensional (2D) to three dimensional information. Production is based either on stereo- or multi-scopic video capturing techniques or on synthetic environments that can mimic or adopt real-life behavior. The resulting 3D media can be transported by providers over the existing telecommunication infrastructure to be consumed by users using single- or multi-view 3D devices such as TVs, goggles, or projectors. The Visual Communication Department in Bell Labs' Application Research Domain has taken on the research challenge to replace a user's avatar in a 3D virtual environment with a real time representation of the user derived from his streaming 3D video image. With this, the tedious process of avatar creation becomes obsolete as people are able to gesture naturally and convey facial expressions within these synthetic worlds. This paper highlights the technical challenges around building and implementing an architecture for innovative and immersive communication systems. We also discuss the technical limitations of the current approach, and pinpoint major open issues.

Old gene duplication facilitates origin and diversification of an innovative communication system—twice

The genetic basis of parallel innovation remains poorly understood due to the rarity of independent origins of the same complex trait among model organisms. We focus on two groups of teleost fishes that independently gained myogenic electric organs underlying electrical communication. Earlier work suggested that a voltage-gated sodium channel gene (Scn4aa), which arose by whole-genome duplication, was neofunctionalized for expression in electric organ and subsequently experienced strong positive selection. However, it was not possible to determine if these changes were temporally linked to the independent origins of myogenic electric organs in both lineages. Here, we test predictions of such a relationship. We show that Scn4aa co-option and rapid sequence evolution were tightly coupled to the two origins of electric organ, providing strong evidence that Scn4aa contributed to parallel innovations underlying the evolutionary diversification of each electric fish group. Independent evolution of electric organs and Scn4aa co-option occurred more than 100 million years following the origin of Scn4aa by duplication. During subsequent diversification of the electrical communication channels, amino acid substitutions in both groups occurred in the same regions of the sodium channel that likely contribute to electric signal variation. Thus, the phenotypic similarities between independent electric fish groups are also associated with striking parallelism at genetic and molecular levels. Our results show that gene duplication can contribute to remarkably similar innovations in repeatable ways even after long waiting periods between gene duplication and the origins of novelty.

A highly innovative global broadband mobile communication system concept

Global mobile communication systems deployed in the 1990s (Iridium and Globalstar) failed to achieve the expected market success. However, recently a second generation of these two LEO constellations have been or will be procured. This shows evidence that global mobile satellite communications are attractive for a certain class of users. Basic requirements for mobile satellite communication networks are global coverage at high elevation angles, continuous availability and most important attractive service offers. For the first two reasons LEO constellations were designed and deployed. The large number of required satellites (remember the original Teledesic concept was designed containing 860 satellites) increases the CAPEX and consequently the service cost. This is probably the major reason for the limited commercial success of Iridium and Globalstar. An ideal global mobile (broadband) communication system shall provide global coverage at high elevation angles (not below e.g. 30°) with the lowest number of satellites. This seems to be contradictory. However, a solution will be presented that achieves global coverage which requires only five satellites and achieves high elevation angles even at polar locations. This orbit constellation is to be complemented with innovative payloads to achieve cost efficient broadband mobile services all over the Globe. Innovative L/S-band payload concepts will be introduced as well as Ka-band payloads.

On Line Media Market and New Advertising Agencies: Analysis of an Italian Case

This article focuses on the profile of agencies which offer communication services through new media related to the information role of the major search engines systems (like Google, Yahoo and others). In particular, attention is paid to firms operating in that context which are taking an innovative profile when compared to communication agencies linked to traditional media. The article develops the following steps: in a first part the characteristics are taken into consideration through innovative communication systems search engines in relation to market trends and the latest configuration of actors linked to them; a second step considers the case of an Italian company acting as an agency in the so-called online media market, highlighting the type of skills and relationships developed through this; finally in a third part some thoughts on the characteristics of the new communication agencies are proposed in comparison with those of the traditional advertising agencies operating with the help of the more traditional mass media. At the conclusion of the article some implications of the analysis are developed and evaluations are made about the development of new business communication services object of our analysis.

Comparison between DS-CDMA and modified Gegenbauer functions for a multiuser communication ultra-wideband system

An innovative multiuser communication system based on the ultra-waveband (UWB) technique is studied. Two coding techniques are proposed: the first is based on direct-sequence code-division multiple access (DS-CDMA) associated with the UWB system. The second innovative technique uses orthogonal functions called modified Gegenbauer functions. To evaluate the performances of these techniques, bit error rate values are calculated and analysed using computer simulations. It is shown that Gegenbauer functions offer superior performance to the previously proposed DS/CDMA-UWB technique for multiuser communications system.

Satellite communications: the contribution of the 5th framework programme and future perspectives

AbstractThe telecommunication sector is of key importance for the European economy. Digitization, secure broadband access and mobility are expected to shift an ever‐growing proportion of the economy on line, thus creating new markets and business opportunities. With the eEurope 2002 and eEurope 2005 initiatives, the European Union has initiated a number of policy actions aiming at favouring the rapid introduction of innovative communication systems, services and applications. Research and development, as supported under the IST programme of the Union, is closely associated to the overall policy picture. The IST programme is notably instrumental in supporting, with a longer‐term approach, key policy orientations such as the pervasive introduction of low cost broadband access, introduction of advanced mobile systems, or migration of networks towards the next generation of Internet protocol, IPv6. Satellite communication form an integral part of this diversified communication landscape, and has also been significantly supported under the 5th Framework Programme. Even if the problematic of the satcom industry are to some extent similar to those of the terrestrial players (e.g. catalysing take up of broadband and advanced mobile markets), the strategies followed by the satcom sector differ from those followed by the terrestrial players. This paper review the current technological approaches of the satcom industry, their relevance in the context of the policy goals of the Union, and how they have been supported under the IST programme. It also introduces briefly how co‐ordination with ESA work has been achieved, and the perspectives for further support, notably under the now starting 6th Framework Programme. Copyright © 2004 John Wiley & Sons, Ltd.

Novel chips for the communication age — Joint effort on III–V electronics a success

With convincing solutions to realize key components of both mobile communication and mm wave sensor systems, a 5-year joint effort on III–V electronics in Germany was recently finalized. Some of the results concerted action that was funded by the Germany Federal Ministry of Education, Science, Research and Technology (BMBF) have already found commercial applications as products of the III–V semiconductor technology which is of particular importance for implementing innovative information and communication systems. As the most renowned representative of this technology GaAs forms the substrate wafer base of high-performance ICs for applications such as mobile radio, optical telecom and ultrafast digital processing with low power dissipation.

Using the Newspaper to Disseminate Vasectomy Information in Kenya

Recent research in Kenya shows that, although there is still a high population growth rate, there is increasing interest among men as well as women in family planning and in limiting family size. Vasectomy, however, is little known and practiced in Kenya. A major reason for this is a general lack of knowledge about the procedure and where it may be obtained. Little effort has been put into addressing the barriers to vasectomy acceptance in Kenya, partly because of the commonly held assumption that Kenyan men would not be interested in the method. Innovative Communication Systems, with the support of the Association for Voluntary Surgical Contraception, implemented a study using the print media to examine this perception. Advertisements providing information about the method were placed in newspapers and a magazine. An unexpectedly large response was received-over 800 written requests for information from all parts of the country. The majority of inquiries were from rural areas, and there was a high proportion of requests from the coastal district, a Muslim area generally considered to be extremely resistant to family planning. A large proportion of inquiries came through a Kiswahili newspaper appealing to lower socioeconomic groups.