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A unique resource providing continuous observations of the critical frequencies since 1935 and layer heights since 1952 has been used to determine the long-term trends above Tromso in Northern Norway (69°N, 19°E). These, and the recent results of Ulich et al. [Ulich, T., Cliverd, M.A., Rishbeth, H. Determining the long-term change in the ionosphere. EOS Trans. 84(52), 581–585, 2003] have then been used to illustrate the effects of layer height changes on radio system modelling and operation by reference to high frequency ground range and skip zone variations. The analysis ignores the effects of the variations in the underlying E-region and changes in the F2 layer critical frequencies. Consequently, the system impact is expected to be higher still. It is shown that a 16 km drop in h m F2 will introduce ground errors of ∼100 km with higher values under certain circumstances. The Tromso analysis indicate that these ground range errors will not occur until the year 2110, however, the results of Ulich et al. [EOS Trans. 84(52), 581–585, 2003] indicate that this condition occurred in the year 2000. This study demonstrates an urgent need to reach a consensus understanding of long-term ionospheric trends. A reassessment of the CCIR and URSI worldwide maps of ionospheric characteristics is likely necessary.

Konventionelle akustische Hörgeräte bleiben trotz stetigen technischen Verbesserungen in ihrer Leistungsfähigkeit beschränkt. Aus physikalischen Gründen können damit Frequenzen über 5 kHz nicht oder nur sehr schwach übertragen werden. Der Hochfrequenzbereich ist aber für das Verstehen von Konsonanten entscheidend. Erst damit kann der Inhalt von Worten erfasst und verstanden werden. Im Weiteren ist das Problem der Lärmverstärkung durch akustische Hörgeräte nicht gelöst. Weitere Problemgebiete sind: hartnäckige Gehörgangsinfekte, Intoleranz für Ohrpassstücke, Feedbackpfeifen und Resonanzen beim Sprechen oder Singen. Implantierbare Hörgeräte wie die Soundbridge von Symphonix-Siemens und das MET von Otologics bieten neue Möglichkeiten der Hörverbesserung und der akustisch schöneren Versorgung. Seit der ersten Implantation einer Soundbridge im Jahr 1996 in der Schweiz profitieren seither weltweit fast tausend Patienten von diesem Quantensprung der Rehabilitation ihrer Schwerhörigkeit. Es handelt sich bei diesen Systemen um Teilimplantate. Ein externer Audioprozessor mit Mikrofon, Batterie, Computerchip und Sendeanlage wird mit Magnethaftung hinter dem Ohr im Haarbereich getragen. In der Regel werden vor einer Implantation zuerst die Möglichkeiten der konventionellen Hörgeräte ausgeschöpft. Im Erwerbsalter ist die Finanzierung in der Schweiz durch die IV gesichert. Im AHV-Alter werden die Kosten des externen Teils von der AHV übernommen. Für die Kosten der Implantation fragen wir die Krankenkassen an. In der Schweiz haben sich bisher erst einige wenige Otologen für dieses neue Gebiet interessiert. Die initial höheren Kosten eines Implantats werden durch die längere Lebensdauer von 20 bis 30 Jahren kompensiert. Konventionelle Hörgeräte müssen alle 5 bis 6 Jahre gewechselt werden. Wegen der qualitativen Verbesserung des Hörens und Verstehens wird die Zahl der Patienten mit implantierten Hörgeräten in den nächsten Jahren deutlich zunehmen. Weitere Implantatsysteme sind in klinischer Erprobung.

In this paper, a group-mobile radio system with private communication capability is proposed. The dispatch radio systems are attractive because of their capability of featuring group calls via the working channels. When a group call is initiated, messages originating from a mobile unit are addressed to the intended group via a dispatch center which administrates the activities among the mobile units. Due to the fact that the make-up in mobile units in the dispatch radio system are organized as a hierarchy, the message exchanges are usually group communications, so that group calls become the main concern in real applications. In this paper, a cryptographic mechanism is utilized to achieve private communication during the message exchanges. Moreover, not only can our scheme provide secure message sharing among the intended mobiles, but it is also possible for the message to be monitored by the leader of the mobiles group. The computing time in our scheme remains acceptable providing a high-speed p...

The Research presented here describes evolving mass media and the emergence of civil society in Croatia at the end of the 20th Century. This case study centers on the development of Hrvatski Radio (Croatia's public-service radio system), and relevant Croat law. Research questions focus on the historical, polital, and legal issues that have shaped Croat radio in the past decade, and the transition of Croatia's public-service broadcasting from an authoritarian to a benevolent system.

This paper introduces some of the research work on the effects of telematics, in this case a radio system, on driver's performance. Twenty-four undergraduate students participated in a series of simulated driving scenarios. In the pre- and post-allocation phases, all participants were required to drive two-four minute phases to establish their baseline scores. In the allocation phase, they were required to tune to a series of local radio stations while performing the same driving scenarios. The results indicated that participants committed more driving errors and violations during the radio-tuning phase than any of the other pre- and post-allocation phases. These errors were manifested in an increased number of crossing the median marking, leaving the roadway, and/or lane deviation. The implications of these results are also outlined in the present paper.

Sir David Brown is the chairman of Motorola UK and the IEE President for 2003/4. This article outlines his life and career in engineering in various industries and the excitement that has come from working at the forefront of engineering. Sir David has worked for Plessey working on the Ptarmigan digital military radio system, for STC working on advanced data switching, as a software manager, and a sales and marketing manager, and finally for Motorola working in GSM. Sir David's involvement with the Faraday lectures and his views on the proposed merger between the IEE, IMechE and IIE are mentioned.

An ad hoc wireless system is an accumulation of self-ruling nodes or terminals that interacts with each other by framing a multi-hop radio system and keeps connectivity in a decentralised way. This implies that it can maintain the system promptly without the need of framework organisation. In spite, there has been a developing enthusiasm for mobile ad hoc networks as the method for giving sudden links to a group of nodes. The energy requirement of a portable node is typically a battery and the battery depletion is one of the real constraints behind the node failure. Entire mobile nodes may not be inside the transmission range of each other thus they need to interact with multi-hop approach. The loss of a unique node can incredibly influence the entire execution of the system. Thus, to utilise the constrained energy source viably and to maximise the life time of the system numerous energy effective routing protocols have been proposed for MANETs that in turn utilise diverse applications to preserve energy. Here it aims to improve the accuracy of performance evaluation therefore it is required to consider the evaluation of protocols at different layers which leads to better energy solutions. The present research will focus on evaluating performance of energy efficient protocols at different layers.

This paper presents the First report of an ongoing to study the effects of trees on radio signals at microwave frequencies. The effects of vegetation media on the planning and design of radio links at microwave and Microwave frequencies are considerable and must be accounted for by radio system operators and users. Measurements have been made to determine the extent of attenuation when propagated through vegetation and also have been carried to be conducted on selected vegetation with various degree of foliation to determine the dependence of losses on vegetation. Also, path geometry and tree geometry are among other parameters under consideration. The results from these experiments compared with standard ITUR-P empirical models and to reflect the dependence of vegetation attenuation on the input parameters under observation.

The time synchronization in the virtual radio system is determined as one of thorny technical problems. Especially in TTC system of signal processing; Aerospace Measurement; Aerospace control; virtual radio; Time synchronization

summary The Hospital Without Walls is an ongoing ambitious project in home telecare that incorporates research into physiological monitoring, low-power radio communication, database storage of physiological data and methods of viewing clinically relevant information from large quantities of stored data. The system records vital signs from patients in their homes using a body-mounted, two-way radio system and a base station located in the home, which transmits data records to a central recording facility every day or in response to predefined emergency events. The prototype system has successfully undergone preliminary clinical trials, with a particular clinical emphasis on monitoring activity using three-axis accelerometers. Our experience with the trial suggests that there are significant differences in the technical design required for a long-term, home monitoring system and one where monitoring takes place in an environment staffed by health professionals.

Emerging approaches to HF communications aim to increase the range of missions and applications HF can support by using higher bandwidths to achieve higher on-air data rates and/or improved communications robustness. Current proposals achieve this in either of two ways: by (i) increasing the bandwidth allocated to a single-carrier modulated waveform, to up to 24 kHz (or possibly higher), or (ii) using existing modulation formats to simultaneously modulate up to 16 carriers in noncontiguous 3 kHz channels. Each of these approaches has inevitable consequences for both radio system performance and spectrum utilization and availability. Both the US Department of Defense and NATO have standards documents (respectively, MIL-STD-188-141C and STANAG 4203) intended to specify the performance and spectral occupancy characteristics of military HF radios. However, these standards have been primarily focused on operation on traditional 3 kHz channels, and do not fully address either of the two proposed Wideband HF (WBHF) approaches. This paper analyzes some key performance impacts of the two WBHF approaches, uses a simple system model to predict the spectrum occupancy and efficiency of the two approaches, and provides recommendations for new and revised requirements to address Wideband HF systems in the applicable US and NATO standards.

Reliable information about the cumulative distribution of surface refractivity gradient is often required in the design of radio systems. Strong negative gradients, or super-refraction, may lead to interference between terrestrial stations, both terrestrial links and satellite earth stations. Predicted positive or sub-refractive gradients are taken into account in determining the minimum antenna heights, to ensure terrestrial links achieve their required availability. This paper reviews sources of refractivity gradient data, and considers how refractivity gradient at a point may relate to an effective value over a terrestrial path.

A variety of network modeling and simulation tools are available, each with its own unique benefits and shortcomings. When a complex model is written for one system, it is sometimes desirable to be able to use that model with a different system. In this paper, we share our experiences in porting a model of a complex radio system from OPNET Modeler to NS-3 at the US Army Research Laboratory.

Synchronization is a vital process for mobile system operations. Yet, in practice, it is not always convenient to derive timing information from stable clock sources. We discuss the inter-base-station timing mechanisms evolved for the two third-generation system proposals CDMA2000 and WCDMA. From the discussion, we review the merits and limitations of both approaches and highlight an alternative method based on self-synchronization. By using self-synchronization in third-generation systems, we can avoid the need for compromising performance through the adoption of asynchronous radio system design.

The Army is facing a number of challenges now and in the future. One of the major challenges is in the power sources arena. As the Army continues to move toward digitizing the battlefield, the need for portable power is increasingly becoming a technological hurdle that must be overcome in order for a soldier to exercise his electronics capabilities without being overburdened by the power sources size, weight and operating/logistical costs. Advanced electronic devices are becoming a critical piece of the soldier's personal battlefield equipment. A soldier with the latest version of the Single-Channel Ground and Airborne Radio System (SINCGARS) is one of the most dangerous weapon systems on the modern battlefield. The ability to accurately navigate and communicate multiplies the soldier's advantage over a less electronic capable enemy. Keeping his personal electronics operational is crucial to giving the soldier the capability to complete his mission successfully. Inherent in keeping the electronic equipment operating is keeping it supplied with batteries. Due to the increased emphasis placed on the modern soldiers electronic equipment, the importance of the portage of the power sources needed to keep this equipment operational has also increased. Recent efforts have focused on hybrid power sources that may enhance discussed capabilities by taking advantage of both high energy sources and high power systems for intermittent power application. This development could lead to a power source with enough energy to meet the Army's preference for a 72-h mission life before the need for resupply.

A few years ago it was recognized that the vision of a truly low-cost, low-power radio-based cable replacement was feasible. Such a ubiquitous link would provide the basis for portable devices to communicate together in an ad hoc fashion by creating personal area networks which have similar advantages to their office environment counterpart, the local area network. Bluetooth/sup TM/ is an effort by a consortium of companies to design a royalty-free technology specification enabling this vision. This article describes the radio system behind the Bluetooth concept. Designing an ad hoc radio system for worldwide usage poses several challenges. The article describes the critical system characteristics and motivates the design choices that have been made.

a new optical-electronic measuring method of mutual orientation between two spatial vehicles is represented, and a corresponding system is devised in this paper. It has advantages of a high measuring precision and rapid calculating speed, compared with radio system, and can be used to help precisely automatically dock two space vehicles. Effective distance is about several tens of meters

The rejection of QPSK interference in a THPPM UWB system using complex adaptive filter and a nonlinear correlation receiver (NCR) with a soft-limiter will be considered in this paper. This system brings a significant performance improvement compared to the system which uses complex adaptive filter and a linear receiver, particularly in the case of high interference power, where its absence leads to the reception loss.

This paper sketches the evolution of a train control system (TCS) and its on-board unit (OBU) for low density traffic lines. The train control system represents a distributed real-time control system consisting of on-board computers on each train, a traffic control center as well as a data radio system. The safety critical software components have been implemented in Ada95 and the system is constantly adopted for different industrial and research projects. The latest modifications dealt with the exchange of the communication mechanisms over the data radio system, the exchange of the data radio system itself and sensor replacements. These modifications have been performed within the realm of the EU funded research project SATLOC and tested in field.

The increasing number of electrical and electronic components in the car has a considerable influence on its safety and environmental compatibility. The legal standards that have to be observed as a result are laid down in the recently modified, so-called Automotive EMC Directive. However, radio systems especially are subject to yet more requirements such as the R&TTE Directive. Using the example of the tire-pressure control system TSS from Beru AG it is explained how manufacturers have so far been obliged to handle these somewhat contradictory specifications and how they have been cooperating in respect of the licensing requirements with the various authorities involved. Now the procedure, tolerated to date, has been transferred to a new Directive.

Cognitive Radio principles were first described at a Keynote Speech by Dr. Joseph Mitola at the IEEE ICASSP Conference in Phoenix in 1999. In this talk Mitola described the principles of a Radio that could help its user to do many things. The vision includes a radio with an understanding of numerous domains ranging from the user's daily routine to an understanding of how to find and efficiently use spectrum and avoid interference. This paper will review Cognitive Radio principles explored by the commercial and defense communities, assessing progress made in the many potential dimensions of Cognitive Radio as an assistant to the radio user. We will utilize the DARPA developed Advanced Wireless Network System / Wireless Network after Next (AWNS/WNaN) radio system and network as the example of a Cognitive Radio capability that provides high levels of adaptivity to the communications radio frequency (RF) environment and the warfighter's mission.

For non-coherent detection based cognitive radio (CR), the required length of the spectrum sensing window is inversely proportional to the primary user’s (PUs) signal strength. When a CR system’s transmission period is fixed, the length of the CR’s transmission window can be inadequate to fully utilize the white space if the corresponding PUs operate in low-SNR regime. We propose a sensing window optimization algorithm in this paper aiming at improving the spectral efficiency of the cognitive Ultra Wideband (UWB) radio system. The proposed algorithm can find the optimal tradeoff between the sensing window length and the desired detection probabilities for the UWB based CR system in low-SNR regime. Compared with the conventional sensing algorithms in which the sensing window is fixed, the proposed algorithm can significantly increase the length of the CR-UWB’s transmission window so as to use the available spectrum more efficiently while guaranteeing the PUs’ operation.

Group Delay variations versus frequency is an essential factor which can cause distortion and degradation in the signals. Usually this is an issue in wideband communication systems, such as satellite communication systems, which are used for transmitting wideband data. However, group delay can also become an issue, when working with high Q antennas, because of the steep phase shift over the frequency. In this paper, it is measured how large group delay variations can become, when going from a low Q antenna to a high Q antenna. The group delay of a low Q antenna is shown to be around 1.3 ns, whereas a high Q antenna has group delay of around 22 ns. It is due to this huge group delay variation characteristics of high Q antennas, that signal distortion might occur in the radio system with high Q antennas.

There are entire books that deal with statistics, logarithms, significant figures, transmission lines, and s-parameters. We are interested in understanding and designing radio receivers and systems, which requires at least a passing knowledge of all these topics and more. This chapter serves as an introduction to many of the basic concepts we will need in later chapters.

An early version of the Bellcorepersonal access communications systems (PACS) specified a method of providing inter-radio system (RS) handoff assuming an ISDN/AIN switching system. To support switching systems without ISDN/AIN capabilities, an alternative approach calledanchor RS handoff has been proposed for PACS. Two possible anchor RS approaches areswitch loopback anddirect connect. This paper studies the performance of the two anchor RS methods. We show that if users exhibit locality of movement, the switch loopback method is better. Otherwise, the direct connect method should be considered.

Until recently, it was taken for granted that radio frequencies for the operation of aeronautical communications, navigation, and surveillance (CNS) systems would be available to meet the requirements of aviation industry growth. Recent Congressional actions aimed at transferring spectrum from the Federal Government to private use, highlight the need to assess carefully the present and future spectral requirements of aviation CNS systems and to use available frequency resources as efficiently as possible when implementing those systems.To illustrate one way in which the Federal Aviation Administration is working to utilize its spectral resources more efficiently, a specific example is presented: the transition of air/ground communications in the 118–137 MHz VHF band from the current analog format to a digital one.

This paper presents a method of predicting the bit-error rate (BER) performance of the global system for mobile communications (GSM) system as a function of the wideband channel parameters obtainable from measured or assumed power delay profiles. Although delay spread is found to be the most useful parameter for the prediction of BER performance, it has been shown that in some conditions delay interval (15 dB) can provide a more accurate prediction mechanism. Thus, based on the delay spread and the delay interval (15 dB), empirical prediction formulas are derived.

Radio observations of the Lyrid meteor shower obtained by a forward scatter radio system (Bologna-Lecce) in 1994 are analysed and discussed. The shower maximum appeared at solar longitude 31.0°(1950.0) and a distinct displacement between the maxima of the short-duration (< 1s) and long-duration (≥ 1s) echoes is observed. The shower has displayed a high activity, but no exceptional burst similar to that one observed in 1982, was recorded. It has been shown that the shower activity continues down to the smallest particle size of which existence in a meteoroid stream means their recent origin.

Cognitive Radio (CR) is an intelligent radio system, which is capable of being aware of the communication environment and consequently adapts to it. With Null Broadening (NB) technique, CR can share the spectrum and coexist with licensed users (LU) by displaying nulls to a certain range of Direction of Arrival (DOA) of LU. In this paper, we present a new CR downlink beamforming method via combining filtering and NB techniques together, which enables CR to broaden and also deepen the nulls towards LU directions. Meanwhile, it also enlarges the width of the main beam to tolerate the DOA ambiguity of CR users. After employing the proposed method, CR directs the main beam towards its own users while putting deeper and wider nulls to the LU in the downlink beamforming. The proposed beamforming scheme causes less interference to LU while sharing the same spectrum.

In this paper a novel technique for implementing heavily bit error protected 8 and 12 kilobits per second (kbps) voice coder (vocoder) based on a 2.4 kbps vocoder specified in Tactical Secure Voice Cryptographic Interoperability Specification (TSVCIS) is compared to the current 16 kbps Continuously Variable Slope Delta Modulation (CVSD) used in several legacy military radios and the Single Channel Ground and Airborne Radio System (SINCGARS). TSVCIS voice significantly outscored CVSD in terms of quality, using the Mean Opinion Score (MOS) and Diagnostic Acceptability Measure (DAM), and intelligibility, from the Diagnostic Rhyme Test (DRT). These tests show that TSVCIS voice delivers significantly higher quality and intelligibility than CVSD when transmitted over noisy communication channels.

The objective of this report is to document the findings from a series of proof-of-concept tests performed by Savannah River National Laboratory (SRNL) R and D Engineering, for the DOE Packaging Certification Program to determine if a viable radio link could be established from within the stainless steel confines of several drum-style DOE certified Type B radioactive materials packagings. Two in-hand, off-the-shelf radio systems were tested. The first system was a Wi-Fi Librestream Onsight{trademark} camera with a Fortress ES820 Access Point and the second was the On-Ramp Wireless Ultra-Link Processing{trademark} (ULP) radio system. These radio systems were tested within the Model 9975 and 9978 Type B packagings at the SRNL. This report documents the test methods and results. A path forward will also be recommended.

This paper presents a design of radio systems for capsule endoscopy operating in the 400 MHz band. The design is conducted through estimating a link budget based on system requirements and limitations for the radio systems. In order to calculate the pathloss accounted in the link budget, a method to estimate the pathloss is introduced that brings a patient-specific pathloss model. This method allows calculating the pathloss estimates between the capsule device in the small intestine and on-body antennas. The results show that the use of an antenna diversity technique is crucial to increase the channel signal-to-noise ratio (SNR) in capsule endoscopy. Also, the location onto which the on-body antennas are attached is important to bring the diversity gain.

Radio communications form an essential part of railway operations. However, across Europe, a range of often incompatible, analogue private mobile radio (PMR) type systems is currently in use. With new digital standards emerging, and increasing European harmonisation, the railway authorities, in line with the EC directive on the harmonisation of European High Speed Railway Network technology, have decided to standardise a new radio system for introduction from 1997 in order to allow interoperability and open competition from industry on a Europe-wide basis. In the paper, the reasons for selecting the Global System for Mobile Communications (GSM) as the basis for the radio system are examined and changes required to provide the enhancements necessary for railway operation are detailed. The resulting technology, which will become available to all GSM operators, might make cellular systems more attractive to current PMR users.

In the late 1920s and early 1930s countries like the United States, the United King dom and Germany experienced an early and rather premature television-boom. In hindsight the 'mechanical' television of those days seems primitive, but at the time it must have looked as if the time of 'seeing at a distance' had finally come, whatever that might eventually come to mean. Under those circumstances parties with a real or an assumed interest would be forced to take decisions with possibly long-lasting effects, based on tentative definitions of the tech nology and its uses, and their own position vis a vis the new medium. As far as Germany, Britain and the USA are concerned, what happened during the boom, as well as its causes and its effects, have been reasonably well documented by now. This study focuses on the case of the Netherlands, a pioneer country in radio broadcasting, with a large electronic industry, but with a radio system that differentiates it from both main types of broadcasting institutions, the public broadcasting monopoly and the private commercial broadcasting system.

Spread-spectrum modulation can be used in a radio system to reduce the likelihood of intercept, as well as providing some protection against jamming and interference. These antijam, anti-interference and low-probability-of-intercept properties are highly desirable in secured communication systems. In addition, spread-spectrum techniques have been proposed to combat spectral congestion by improving the efficiency of spectrum utilisation. Spread-spectrum techniques are also widely used in ranging systems and in local-area networks (LANs) or other multiple-access systems. In the present article, the three main spread-spectrum techniques are outlined and then applications of frequency-hopping systems and some of the techniques used are described.

Instrumental monitoring is being increasingly employed in the postoperative phase after microsurgery. For this purpose, laser Doppler flowmetry has proven to be very useful. Monitoring of the perfusion of tissue with blood is mainly by clinical examination, which, however, requires the physical presence of the observer, and this is generally not possible on a continuous basis. By connecting up a laser Doppler unit with a computer and telephone modem and making use of the in-house radio system, it proved possible to produce an automatic emergency call system that responds to a worsening of perfusion and alerts the responsible doctor. For this purpose, the software program "call-doc" was developed, which provides the necessary monitoring and control functions. A general perfusion-independent emergency call can also be triggered at the touch of a button.

The article analyzes the requirements for radio system that provides navigation and landing operations of flying vehicles (helicopters). Assessed the possibility of applying for such operations existing systems that perform sim-ilar functions. The structure of navigation and landing radio system for the vehicle type "helicopter" is proposed.

Cognitive MANETs are likely to be complex radio systems. We already know that no single MANET solution can address all environments that may be encountered; such is the rationale of an ad hoc network that it must address the networking demands of unforeseen scenarios. Rather, a cognitive MANET should be viewed as a feature-rich radio system, i.e. one which has access to a range of radio and network components, each suited to different demands. Such a reconfigurable system requires cognitive functionality to self-architect the radios when they are deployed in addition to the cognitive functionality required for the various layers to self-organise. However, any cognitive decision-making process requires awareness of the world for which it is trying to optimise the system. This chapter introduces the concept of an environment–mobility interaction map, a persistent internal representation of the network which captures the presence of areas in the network’s environment in which particular, sustained, mobility dynamics are observed. Such a self-generated map enables the cognitive MANET to plan a response to challenges brought about by these network dynamics.

This paper presents a brief chronology of the origin and developments of wireless (or radio) communications, according to the following pattern: it gives credit to some of the scientists who performed the initial observations and the understanding of electric and magnetic phenomena; it mentions the experiments and inventions carried out towards the evolution of scientific and engineering models; and focuses on the implementation of practical wireless systems. The presentation leads us to conclude that the invention and development of wireless/radio system can neither be credited to one individual nor to one specific country. The chronology strongly indicates an overlapping of human thinking in time in many countries. This fact precludes the possibility of giving the title of Father of Radio to one individual.

This paper presents system-level modelling of potential multiband orthogonal frequency division multiplexed ultra wideband (UWB) system. System performance is measured using bit error rate (BER) and signal-to-noise ratio. The conducted system analysis demonstrated that the BER is equal to or less than 0.1%, for 75% of stable (i.e. transmitter is on waist) and 61% of unstable transmitter locations (i.e. transmitter is on wrist) respectively. This demonstrates promising applications of the proposed UWB body-centric radio system.

As security systems integrate more Information Technology the design of these systems has tended to become more complex. Some of the most difficult issues in designing Complex Security Systems (CSS) are: ● Capturing Requirements ● Defining Hardware Interfaces ● Defining Software Interfaces ● Integrating Technologies ○ Radio Systems ○ Voice Over IP Systems ○ Situational Awareness Systems

The COST2100 channel model is a reference channel model which provides dynamic multiple-input multiple-output channel responses for radio system simulations. In this paper, channels created by the COST2100 model were compared to channel measurements in order to understand behaviours of the model. Model parameters of the COST2100 model were derived by dynamic double-directional channel measurements with which the channel realizations from the COST2100 model were compared. Delay and angular spreads were used as a simple but important metric for the comparison. Despite a fundamental difference that the COST2100 model is a geometry-based stochastic model while the channel measurements are obtained in deterministic environments, the comparison revealed an acceptable level of agreement for practical channel simulations.

The importance of the experiments realized by Guglielmo Marconi on the premises of Villa Griffone were probably already universally considered a fundamental step for understanding propagation in real environment, a key point in successful operation of a radio system. Thousands of visitors at the Villa and at the Marconi Museum are evidence of that. However, this official recognition by the IEEE that these experiments marked the beginning of the new era of wireless communication is the proper seal for the adventure of the Marconi genius, started in Italy and continued all over the world for more than forty years.

Measurement-based methods for the reassignment of a call to another time-slot with less cochannel interference on a time-division multiple access (TDMA) radio link are described and evaluated using a discrete-event simulation. Portable radio access, transfer triggering, and time-slot selection are modeled using an integrated radio and traffic call model. Results showed that link quality can be maintained with a low transfer rate, even under busy conditions. Regeneration of transfers was minimal. Performance was robust with respect to trigger measurement error, whereas the dynamic range of transmission quality measurement was found to be more critical in maintaining quality. Hysteresis reduced the rate of time-slot transfer while only minimally affecting quality. >

This work will address the challenges to facilitate the development of a high capacity radio system for a small, miniaturized electronic pill device that can be swallowable or implantable in human body in order to detect biological signals or capture images that could eventually be used for diagnostic and therapeutic purposes. In addition to reviewing and discussing the recent attempts in electronic pill technology, a wideband (UWB) telemetry system aimed for the development of an electronic pill will be presented in this paper. We have successfully realized more than half a meter UWB link under conditions emulating an implant