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In this paper a modified printed dipole is proposed for mobile terminals operating in the first band of Personal Communication System (PCS) that is ranging from 800 to 900 MHz. One of the most important features of this kind of antenna is its wide bandwidth as required in the mentioned band. The modified design of the proposed antenna allows the user to move in any direction as is usual in mobile communications. The results of this article include an analytical design, simulations that have been performed numerically using a Finite Element Method (FEM) computational tool, structure optimization in order to maximize the antenna bandwidth and experimental measurements with the aim of spatial evaluating of electromagnetic radiated fields.

Novel design of Swastik shape patch antenna is proposed for realizing circular polarized response. Two pairs of orthogonal rectangular slots, which realize swastika shape configuration, yield tuning in between the TM01 and TM10 mode frequencies of equivalent square patch that along with modified TM11 mode yields impedance and axial ratio bandwidth of 565 MHz (47.18%) and 43 MHz (4%), respectively. Proposed antenna yields broadside gain of above 6 dBi over most of the impedance bandwidth with peak gain close to 7 dBi. Proposed configuration with given bandwidth and gain characteristics can find applications in mobile base station communication antennas as well as in personal communication systems.

International audience; This paper presents the results obtained from 60 GHz propagation measurement campaigns in indoor environments. These measurements are performed in the frequency domain and are based on the use of a vector network analyzer (VNA). The analysis of the results makes it possible to characterize the propagation channel. In first measurement campaign, we show the influence of different types of antennas on the path loss characteristics in a hallway, while in the second campaign results highlight the effect of the type of antenna of the access point (AP) and its position on the angular impulse response of the channel inside a meeting room. All of these results are intended to lead to rules for the deployment of wireless high-speed local and personal area networks (WLANs/WPANs). © 2019 IEEE.

A novel printed version of the classic volcano smoke antenna is presented. Its remarkable bandwidth goes from 700 MHz up to 6 GHz for a VSWR 90%. The radiation patterns stay almost omnidirectional. The simulated results and the measurement data exhibited an excellent agreement. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:2592–2595, 2016

Technology has revolutionized medical practices by enabling more convenient and non-intrusive monitoring of patient's health, leading to next generation ubiquitous healthcare (u-healthcare). The exploitation of the Internet protocol version 6 addressing space along with the miniaturization of electronic devices has fostered providing interoperability and connectivity of wearable sensor devices in wireless body area networks to the Internet of Things. In this paper, we propose to integrate the IPv6 over low power wireless personal area network (6LoWPAN) to the u-healthcare monitoring system architecture. The main objective is to study the feasibility of the 6LoWPAN-enabled platform in real-world scenarios dealing with medical data. The performance evaluation of this platform is carried out initially through simulations using OMNet++ and then supported by an experimental study using sensor motes and a customized micro-computing unit. Performance metrics such as throughput, end-to-end delay, packet error rate, and energy consumption are investigated under acute health conditions, where patient's health information has to be sent continuously and at maximum rate to the care provider. The obtained results show that the proposed 6LoWPAN solution fulfills the main quality of service requirements of u-healthcare applications. Copyright 2015 John Wiley & Sons, Ltd. Copyright 2015 John Wiley & Sons, Ltd. Scopus

Reducing the volume of location updates and cost of searching for location information are two important issues for tracking mobile users in personal communication systems. Many approaches have been proposed to improve both the location update traffic and searching costs. Some of these approaches can reduce access cost and some other approaches can reduce the location update cost and location update rate. In this paper, we shall propose a new approach for reducing both location update cost and searching cost (for finding mobile users location information). The new scheme called Virtual Overlap Region with Forwarding Pointer (VORFP) uses the forwarding pointer and the virtual overlap region concepts. The virtual overlap region technique is a good method for reducing the location update traffic, especially when a user backs and forths between adjacent cells. Our performance evaluations show that VORFP can significantly reduce searching cost and update cost.

The potential implementation of personal communication systems inside buildings requires a thorough understanding of signal propagation within buildings. As practical measurements are costly, difficult in accuracy, and time consuming that translate into costly service for the consumer, there is an increasing demand for efficient and accurate simulation-based indoor radio propagation prediction tools. Therefore, this study explores a new, efficient, and faster ray-tracing technique based on the Binary Angle Division algorithm for indoor radio signal prediction. The obtained simulated results are compared with other existing techniques to prove the superiority of the proposed algorithm in terms of both computational efficiency and accuracy. The results obtained from this study show satisfactory performance and good agreement with the simulated results.

Mobile networks have experienced a sharp expansion in the population of mobile clients/subscribers. Such growth incurs additional expending of the bandwidth resources for network cost management. For future PCS (Personal Communication Services) networks, it is desirable to devise mobile networks that make resourceful use of the limited radio bandwidth. Effective mobility and location management is a way to realize such efficiency. This paper surveys different location management strategies and cost planning for personal communication systems. The stress is on how to minimize both the location update and paging costs from the wireless and wired networks.

Cataloged from PDF version of article. Mobility prediction is one of the most essential issues that need to be explored for mobility management in mobile computing systems. In this paper, we propose a new algorithm for predicting the next inter-cell movement of a mobile user in a Personal Communication Systems network. In the first phase of our threephase algorithm, user mobility patterns are mined from the history of mobile user trajectories. In the second phase, mobility rules are extracted from these patterns, and in the last phase, mobility predictions are accomplished by using these rules. The performance of the proposed algorithm is evaluated through simulation as compared to two other prediction methods. The performance results obtained in terms of Precision and Recall indicate that our method can make more accurate predictions than the other methods. 2004 Elsevier B.V. All rights reserved.

We present a new TDMA-based scheme intended for carrying traffic with diverse QoS requirements in mobile environments, e.g., Personal Communication Systems (PCS). In contrast to most other TDMA protocols for mobile applications, instead of trying to fit the offered traffic to the slot size, our solution adapts the slot size to the offered traffic. This feature is combined with a dynamic and responsive bandwidth scheduler. As demonstrated by our performance studies, the proposed scheme is more flexible and incurs lower bandwidth overhead than other TDMA-based solutions.

We report our investigation into single-feed dual-frequency planar inverted F antenna (PIFA) designs which make use of LC resonators (or "RF traps"). We introduce three basic methods for incorporating the LC resonator into the PIFA, including a variant of the meandering PIFA. Experimental results are provided and these show that dual-frequency operation at 900 (cellular systems) and 1800 MHz (personal communication systems) can be achieved for all three designs.

Micro and pico cell planning strategies are adopted in personal communication systems (PCS) in order to increase their capacity. The usage of the upper UHF band in combination with greater bandwidth is already proposed by telecom engineers in order to achieve the promised service quality and data rates. These strategies are characterized by an increased number of cells in specific geographical areas with the corresponding operating base transceiving stations (BTS) located at relatively low heights above the street level. In this case, the cell planning procedure in linear streets under line-of-sight (LOS) conditions needs further study concerning the technical characteristics of the PCS. In this paper, the propagation characteristics of a DCS 1800 system are investigated on a theoretical and experimental basis in a specific geographical area (center of Patras City in Northern Pelloponesse). An improved RF propagation model is proposed in order to determine the propagation path losses occurring under certain multipath fading conditions. Hence an optimum determination of a system's cellular area can be achieved. Copyright © 2001 John Wiley & Sons, Ltd.

We propose a novel SIR weighting postdetection combining diversity scheme with a new accurate SIR estimation method. The SIR is estimated and used as the weighting factor to compensate severe cochannel interference, one of the most important issues for PCS in terms of frequency utilization. The improvement offered by the proposal depends on SIR estimation accuracy. The SIR is, in this paper, estimated by a matched filter where the auto-correlation between received signal and unique word is calculated. Computer simulations confirm that the SIR of each diversity branch can be estimated easily and accurately by the proposed SIR estimation method. The proposed diversity scheme achieves a performance very close to that of ideal SINR weighting diversity under Rayleigh fading with severe cochannel interference. When average SIR = 10 dB and the number of branches (L)=4, the proposed diversity scheme lowers the required Eb/N0 by 5 dB at BER = 1×10-3 compared to conventional maximal ratio combining diversity. This paper also presents the unique word length required to realize adequate performance, i.e., robustness against high-pitch Rayleigh fading.

Spatial filtering using adaptive or smart antennas has emerged as a promising technique to improve the performance of cellular mobile systems. This paper presents an overview of smart antennas in terms of key characteristics, options, challenges and benefits, in the context of current, but also with a view towards future, generation personal communication systems.

Handoff support is one of the key elements in cellular Personal Communication Systems (PCS). Traditional approaches hide handoff support from the subscriber. However, the main difficulty in handoff support stems from terminal mobility which can only be controlled by the subscriber, who may again have different requirements of mobility support under different environments. Therefore, we suggest that the subscriber should participate in handoff support in the following manner: first, the subscriber is encouraged to declare the requirement of mobility support at call setup time; second, when a handoff cannot be supported, the subscriber should be informed in advance so that (s)he can decide whether or not to control movement since a subscriber may sacrifice mobility for maintaining communication in progress. This approach can reduce call dropping rate and improve resource utilization. We will describe this approach and propose a service classification for mobility support in this paper.

When the mechanisms of fading channels were first modeled in the 1950s and 1960s, the ideas were primarily applied to over-the-horizon communications covering a wide range of frequency bands. The 3-30 MHz high-frequency (HF) band is used for ionospheric communications, and the 300 MHz-3 GHz ultra-high-frequency (UHF) and 3-30 GHz super-high-frequency (SHF) bands are used for tropospheric scatter. Although the fading effects in a mobile radio system are somewhat different than those in ionospheric and tropospheric channels, the early models are still quite useful to help characterize fading effects in mobile digital communication systems. This tutorial addresses Rayleigh fading primarily in the UHF band. That affects mobile systems such as cellular and personal communication systems (PCS). Part I of the tutorial itemizes the fundamental fading manifestations and types of degradation.

Mobility tracking is concerned with finding a mobile subscriber (MS) within the area serviced by the wireless network. The two basic operations for tracking an MS, location updating and paging, constitute additional load on the wireless network. The total cost of updating and paging can be minimized by optimally dividing the service area into location registration (LR) areas. There are various factors affecting this cost, including the mobility and call patterns of the individual MS, the shape, size and orientation of the LR area, and the method of searching for the MS within the LR area. Based on various mobility patterns of users and network architecture, the design of the LR area is formulated as a combinatorial optimization problem. The objective is to minimize the location update cost subject to a constraint on the size of the LR area.

This article considers various regulatory aspects related to the deployment of third-generation mobile personal communication systems within the framework of IMT-2000 with special emphasis on international regulations, particularly in relation to the standards and regulatory provisions established in the ITU.

Mobility tracking is concerned with finding a mobile subscriber (MS) within the area serviced by the wireless network. The two basic operations for tracking an MS, location updating and paging, constitute additional load on the wireless network. The total cost of updating and paging can be minimized by optimally dividing the cellular area into location registration (LR) areas. In current systems broadcast paging messages are sent within the LR area to alert the MS of an incoming call. In this paper we propose a selective paging strategy which uses the MS mobility and call patterns to minimize the cost of locating an MS within an LR area subject to a constraint on the delay in locating the MS.

This paper describes and analyzes a medium access protocol for wireless personal communication networks serving integrated traffic. A multi-priority mechanism, which is implemented and controlled explicitly by the users and without any involvement from the network is incorporated into the protocol. We examine the proposed protocol under reservation and non-reservation policies and evaluate its performance when handling integrated voice and data traffic. The proposed protocol is suitable to be used in Personal Communication Systems aiming to provide integrated (voice/data) services.

Microcellular and distributed antenna systems are two promising candidates for implementing personal communication systems. Antenna interconnection strategies for these systems are studied in order to determine cost-efficient as well as robust and flexible architectures in hexagonal layouts. To this end, some results from minimal networks theory are used, in particular, those dealing with the problem of Steiner trees. The significant reduction in conduit and cable lengths that the Steiner minimal tree (SMT) architecture provides over the star type, especially in large networks, is demonstrated. It is further shown that the SMT architecture also provides more flexibility and robustness compared to the star type. The suboptimal, but easy-to-construct, minimal spanning tree (MST) architecture is given as well, and it is compared to the SMT and star types.

The past few years have witnessed some of the major breakthroughs in data communications technologies and services. Most notably, broadband networking (e.g., Asynchronous Transfer Mode), Client/Server Computing, and Personal Communication Systems have revolutionized the field of data communication. These new technologies will have important implications for end-users as well as network managers and administrators. This article presents a review of the new networking technologies and an evaluation of each.

In this paper, we discuss views concerning different approaches to the analysis of personal communication systems (PCSs): an outside observer's point of view, a user's point of view, and a base station's point of view. In these three approaches the paper focuses on the handover mechanism rather than on the data traffic modeling. In particular, we reexamine these different methods of analysis, combine these views with our approach, and propose a new queueing model. We take into account the speed factor and show that the ordinary measurements that are based on the state probabilities are not appropriate. In addition, we propose a layered queueing model in which low-speed and high-speed users are treated differently.

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Masquerading and eavesdropping are major threats to the security of wireless communications. To provide proper protection for the communication of the wireless link, contents of the communication should be enciphered and mutual authentication should be conducted between the subscriber and the serving network. Several protocols have been proposed by standards bodies and independent researchers in recent years to counteract these threats. However, the strength of these protocols is usually weakened in the roaming environment where the security breach of a visited network could lead to persistent damages to subscribers who visit. The subscriber's identity is not well protected in most protocols, and appropriate mechanisms solving disputes on roaming bills are not supported either. To solve these problems, new authentication protocols are proposed in this paper with new security features that have not been fully explored before.

The present survey paper summarizes radio-propagation measurements and models for emerging wireless personal-communication systems. Both indoor and microcell-propagation environments are considered, and the problem of RF penetration into buildings is identified as an important area of research for emerging wireless-communication systems. >