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Aims: First, to describe the rationale for developing a combined summary score, the Healthy and Sustainable Dietary and Physical Activity habits (HSDPA) score, incorporating four selected dietary and physical activity aspects: (a) the New Nordic Diet, (b) local and sustainable foods, (c) active transportation and (d) non-exercise outdoor activities. Secondly, to describe the experiences from constructing the HSDPA score. Methods: Relevant literature covering the four aspects of interest was reviewed to secure a well-grounded rationale and a theory-based approach. To measure compliance with such a broad approach targeting diet, physical activity, health and environmental sustainability, the HSDPA score was constructed including one subscale for each aspect. The four subscales were constructed from questionnaire items and were equally weighted, entailing a range from 0–10 points, hence the total HSDPA score ranged from 0–40 points. Results: In retrospect, we believe that the rationale for creating the HSDPA score is reasonable. Still, emphasizing fewer, but the most relevant aspects, such as reduced meat consumption and active transportation, may represent a more functional solution than the broad approach suggested herein, both for promoting public health and environmental sustainability, and for developing a feasible measurement tool. Conclusions: Our experiences illustrate the importance of methodological perspectives and scrutiny related to both the development and testing of complex summary scores. Nevertheless, we think that combined summary scores could be applicable for use within epidemiological studies and for measuring the effects of interventions, if accounting for the methodological limitations as far as possible.

La necesidad la tecnología HSPA+ or Evolved High Speed Packet Access también es conocido como HSPA evolution, surgió con la creciente utilización de los datos y los usuarios que desean velocidades de descarga mucho más eficiente, en Ecuador CNT para el 2014 se propuso implementar 491 radio bases HSPA+ para alcanzar una cobertura del 84 por ciento de la población ecuatoriana y desde entonces ha alcanzado una excelente cobertura a nivel nacional. El objetivo de este trabajo es realizar un análisis de la tecnología HSPA +, así como también su evolución a partir de la generación de los celulares, en la segunda etapa se hablará de HSPA sus ventajas, arquitectura de red, estructura de protocolos en la cual se verá la capa MAC y la capa RLC, en la tercera etapa HSDPA su arquitectura de red, sus principales mejoras, estructura de protocolos, handover en HSDPA, en la cuarta etapa HSUPA su arquitectura de red, estructura de protocolos, sus principales mejoras, sus canales y handover HSUPA, en la etapa 5 hablaremos la evolución de HSPA + dentro del release 7.AbstractThe need for HSPA + technology or Evolved High Speed Packet Access is also known as HSPA evolution, emerged with the growing use of data and users wanting download speeds much more efficient, in Ecuador CNT for 2014 set out to implement 491 radio bases HSPA + to reach coverage of 84 percent of the Ecuadorian population and since then reaching an excellent coverage at the national level. The objective of this work is to perform an analysis of the HSPA + technology, as well as its evolution from the generation of the cellular, in the second stage we will talk about HSPA its advantages, network architecture, structure of protocols in which we will see The MAC layer and the RLC layer, in the third stage HSDPA its network architecture, its main improvements, protocol structure, handover in HSDPA, in the fourth stage HSUPA its network architecture, protocol structure, its main improvements, its channels And handover HSUPA, in stage 5 we will discuss the evolution of HSPA + within release 7

This study aims to determine the mapping rule for signal-to-interference ratio (SIR) to channel quality indicator (CQI) based on DC-HSDPA real field measurements. The measurements were performed using the TEMS Investigation Tool at 85 different propagation mediums. The measurement results showed that the SIR-to-CQI mapping methods in the literature were insufficient to characterize actual radio environments; thus, proposal of a new empirical SIR-to-CQI mapping rule was aimed. This rule provides substantially better performance than the existing methods, and with this rule CQI can be generated from SIR with an accuracy of around 90% for DC-HSDPA systems. © TUBITAK.

With the influence of customer growth and environmental influences from an HSDPA network in the form of nodeB which stands in the Malang City area, it can experience integration. This causes measurements to be carried out continuously and periodically to provide the latest radio environmental information. The vendor as the network operator performs optimization in order to provide customers with the best quality service. One of them is in the form of network performance which aims to ensure that network resources are used efficiently. The method in achieving network optimization that is still used by vendors in Indonesia is by measuring network performance, then analyzing the results of measuring network performance and finally network tuning. For measuring network performance using a test drive. Of the 13 nodeB in Lowokwaru District, Malang City, it is necessary to optimize the HSDPA network with the suggestion of a downtilt antenna on the Ketawanggede nodeB sector 3, which is 2º The results of the calculation of the path loss parameters from each of the 13 nodeBs obtained the highest value of 125.31 dB at nodeB Ketawanggede and the lowest 114.29 dB at nodeB Vinolia Malang sector 3. The results of the RSCP parameter calculation at 13 nodeB obtained the best value at nodeB Vinolia Malang sector 3 with RSCP of -69.29dBm. While the worst value at nodeB Ketawanggede with RSCP is -80.31dBm.

A low-complexity soft-output decoding algorithm is proposed for MIMO detection. A VLSI architecture is further proposed to support high-throughput MIMO decoding. The simulation and implementation results show that the proposed algorithm and VLSI architecture can approach the performance of the conventional soft-output MIMO decoding algorithms with lower complexity and higher decoding throughput. The proposed algorithm and VLSI architecture would be promising for emerging MIMO applications such as HSDPA, 802.11n, 802.16e and 802.20. It also shows potentials for the MAGNET date rate classes.

He joined SK Telecom at 1997, and worked for the IRIDIUM project and 3GPP standardization. From 2004, he has not only contributed commercialization of WCDMA and HSDPA/HSUPA, but also took a responsibility for the R&D strategy of SK Telecom. Since 2009, he has successfully led the Korea-first LTE launch, the world-first multi-carrier deployment, the world-first nation-wide HD Voice (VoLTE) commercialization, the worldfirst LTE-A (Carrier Aggregation) commercialization, and directing LTE evolution and beyond LTE-A of SK Telecom as head of Access Network Lab.

The purpose of this research is to effectively analyze the application of 3G especially in relation to the implementation of UMTS technology. An extensive examination of the UMTS architecture will be explained. The prime need of conducting an extensive research on this topic is to get an insight into the principle areas that enhance the speed and data rates of the organizational operations. The study will also incorporate a brief discussion of the HSDPA and HSUPA in the latter part of the paper for better demonstration of the efficacy offered by the 3G technology. For the purpose of addressing the aforementioned problems, it is highly recommended that the systems and networks make use of the effective and efficient 3G technologies. Therefore, this paper will study the application of 3G with relation to the incorporation of UMTS technology. IV. Methodology For the conduction of research on the application of 3G technology in the organizations, a thorough primary data analysis has been carried out. The reason for the research is to get an insight into the implementation and importance of the implementation of 3G technologies. For this purpose, the computer engineers and architects of a number of different organizations in the region of US will be interviewed about the importance of the concept. The past studies of different authors will also be researched thoroughly for acquiring a better understanding of the relevant research areas. Some authentic libraries to be used for collecting secondary data for this research may include; Phoenix, JStor and EBSCOhost. And we have used ATOLL simulation to illustrate some of the differences.

This paper focuses on the HSDPA for MIMO cellular networks. To understand the role of HSDPA and the limitations of the existing work a survey is conducted in this paper. The impact of HSDPA can play a key role in upcoming cellular services where continuous streaming of data is required. HSDPA employs fast retransmission scheme, new frame structure and new adaptive higher order modulation scheme.FUS (far user streaming) will be used to provide the enhanced services of HSDPA to near user as well as far user fairly at the cost of little delay.

With the explosive growth of multimedia applications, video transmission over HSDPA networks has attracted more and more attentions. Particularly in the last few years, lots of special transmission schemes have been proposed to improve the end-to-end qualities of mobile video applications. However, due to lack of a common video delivery simulation platform over HSDPA networks, the researchers have met obstacles in evaluating and comparing the performance of these schemes in a unified simulation environment. To fill this gap, a common system-level video transmission simulation platform is proposed in this paper, which is implemented specially for the HSDPA networks. To the best of our knowledge, this platform is the first one in integrating the video encoder/decoder, the video quality evaluator and the HSDPA simulator together. In this way, the researchers can study and analyze not only the overall system performance of the video-aware cross-layer transmission solutions, but also explore the influence and interaction of those separate sub-layers in the HSDPA wireless networks, such as the video application-layer, the transmission control layer, the HSDPA MAC layer, and the physical layer. Moreover, to test and verify our simulation platform, we implement eight representative fast scheduling algorithms over the HSDPA networks, and evaluate their transmission performances for the H.264/AVC video applications. Experimental simulation results demonstrate the effectiveness and rationality of our simulation system.

In CDMA-based systems, recently, researches on chip-level equalization have been studied in order to improve receiving performance when supporting high-rate data services. In this paper, we consider a chip-level LMMSE (linear minimum mean-squared error) receiver for D-TxAA (dual stream transmit antenna array) based single stream HSDPA MIMO systems using precoding weights. First, we will derive precoding weights for maximizing the total instantaneous received power. We will also analyze the effects of both transmit delay of precoding weights and mobile velocity on chip-level LMMSE receivers, which is verified through computer simulations in various mobile channel environments.

High-Speed Downlink Protocol Access (HSDPA) is a mobile telephony protocol. It is designed to increase data capacity and transfer rate. This paper presents a resource allocation strategy in the HSDPA broadband network. An admission check is proposed. It divides the coverage area of a base station (Node-B) into several regions based on the principle of Adaptive Modulation and Coding (AMC) efficiency. The call admission control (CAC) mechanism distinguishes two RT and NRT traffic according to the type of service requested by the user. It dynamically allocates an effective bandwidth to each accepted call in the system based on its modulation efficiency and maintains its initial rate during its communication.

An opportunistic downlink scheduling algorithm, which is referred to as Scheduling scheme for Multiple Mobile Terminals Serving the same User equipment (SMMTSU), is presented for the case when there exists User Equipment (UE) that is served by multiple Mobile Terminals (MTs) in a time-slotted cellular system. We study three scenarios, namely (i) when the MTs are served by the same cellular provider but scheduler has no knowledge of the presence of such UEs; (ii) when the MTs are served by the same cellular provider and the scheduler located in the base station knows the presence of such UEs; and (iii) when such MTs are served by different cellular providers. We establish the optimality and present the main properties of SMMTSU for scenario (ii). In scenario (iii), we show that it is better to use the MTs from one cellular provider using SMMTSU rather than from different cellular providers. Simulations under High-Speed Down-link Packet Access (HSDPA) model are implemented which show that SMMTSU works well and provides an approximately 20% throughput improvement for the UEs in scenario (ii) as compared to scenario (i). The simulation results also show that there is generally a 7% throughput benefit if the users take service from a single cellular provider.

A new queuing model is proposed for the performance evaluation of the High Speed Downlink Packet Access (HSDPA) protocol, with respect to a specified user, in UMTS networks. This analytical model is an integrated one capable of capturing many complicated features of HSDPA operation such as correlated and bursty traffic, channel fading, channel allocation policy and packet-losses in the air interface. The validation of the model for comparing the user terminal categories is performed with a detailed simulation of HSDPA terminals with "real" traffic traces. It is shown that the model is quite accurate to predict and compare the throughput of the HSDPA terminal categories.

A multiple transmit antenna, single receive antenna (per receiver) downlink channel with limited channel feedback is considered. Given a constraint on the total system-wide channel feedback, the following question is considered: is it preferable to get low-rate feedback from a large number of receivers or to receive high-rate/high-quality feedback from a smaller number of (randomly selected) receivers. Acquiring feedback from many users allows multi-user diversity to be exploited, while highrate feedback allows for very precise selection of beamforming directions. It is shown that systems in which a limited number of users feedback high-rate channel information significantly outperform low-rate/many user systems. The marginal benefit of channel feedback is very significant up to the point where the CSI is essentially perfect.

In high-speed downlink packet access (HSDPA), the combination of adaptive modulation and coding, hybrid automatic repeat request, and an extended multicode operation has replaced two fundamental aspects of wideband code division multiple access systems, namely, variable spreading factor and fast power control. Despite its enhanced characteristics, the HSDPA operation can be problematic when the majority of incoming traffic load consists of low data rate delay-sensitive services such as mobile voice-over-Internet Protocol. To tackle this case, we propose an enhanced HSDPA operation that exploits multiple layers of the channelization code tree through a specifically designed packet scheduling and code allocation process. Enhanced HSDPA, when compared with the conventional HSDPA, provides a more flexible sharing of the available capacity and is able to increase the number of users that can be served with the required quality of service in terms of packet delay. The efficiency of the proposed scheme is confirmed by simulation results. Copyright © 2011 John Wiley & Sons, Ltd.

An unusual compound Zn1.5(Hsdpa)(bpy)1.5(H2O)4 (1) comprising two isolated coordination polymers has been obtained by hydrothermal reactions, in which helical channels of a 3D host framework A [Zn(Hsdpa)(bpy)(H2O)2]− are filled with the guest infinite 1D polymer chains B [Zn0.5(bpy)0.5(H2O)2]+.

Telemedicine system means a remote support system among 4 remote telemedicine services of u-Health. A currently available service in Korea is the one checking and maintaining patient’s status and supporting in emergency through video communication between an ambulance transferring patients and hospital under HSDPA and WiBro environment with coding of MPEG-2 and MPEG-4. With that, this paper improves the stability of the current telemedicine system service of ambulance confirms the improvement compared to the old system by generating a system communicating by RTP/RTCP under coding process through H.264/AVC after converting RGB video to YUV in order to improve network efficiency.

High Speed Packet Access (HSPA) Holma H, Toskala A (in HSDPA/HSUPA for UMTS, 2006) is expected to provide enough bandwidth for voice over IP (VoIP) service. In this article we assess the performance of VoIP over HSPA with different VoIP clients and voice codecs. The simulations results show that VoIP can have a good voice quality over HSPA if a proper VoIP client and codec is used. However it is possible that the delay can increase with early HSPA implementations (mobile, network).

This article has discussed the theoretical and modeling aspects of the RP_CC schemes in detail. There are several combinations of CC algorithms that have been vastly investigated, tested, and validated for the performance of HSDPA network. The simulation results confirm that the combined usage of RP_CC algorithms can achieve a significantly better overall performance for the HSDPA network compared with other configurations. Such combined CC mechanisms can optimize the effective link utilization by minimizing the higher layer retransmissions and can also achieve high end-user throughputs.

This article presents various traffic separation approaches to transmit HSPA (HSDPA/HSUPA) traffic in the existing ATM-based UMTS Radio Access Network, together with Release 99 (R99) traffic. The traffic separation technique enables QoS differentiations of HSPA and R99 traffic, while aiming to achieve a maximum utilization of the transport resources in the radio access network. The potential benefit of applying traffic separation and its impact on the performance of the transport network as well as the end users are explored in this article. The quantitative evaluations are provided by simulations. The results presented are obtained from a UMTS simulation model developed in this work which can transmit HSDPA and HSUPA traffic as well as R99 traffic simultaneously. The presented results demonstrate that applying traffic separation between HSPA and R99 traffic can considerably improve the performance of both HSPA and R99 traffic, and as well bring significant gain on efficient bandwidth utilization.

To restore the orthogonality of the spreading code, an equalizer is adopted at the receiving site for a HSDPA system. In this paper, BER performance and complexity analysis of various equalizers are compared under different outdoor channels. Results show that with tapering technique, the fast FFT-circulant and Expand-truncate equalizers can ease the condition number problem at a high SNR multipath channel. Simulations also show that the CG method has a satisfactory BER improvement. However, its performance depends notably on the number of iterations.

In this paper, the performance of HAPs (High Altitude Platforms) UMTS HSDPA (High Speed Downlink Packet Access) is studied for different scenarios and two directions (0^o and 30^o) within the cell where the network under study is assumed to have 61 cells. It is concluded that, for urban zone users, the effective range is lower than the effective range for users in rural zones. It is shown that in rural zones, the HSDPA mode can support the modulation 16QAM with 7/8 code rate when cells are not fully loaded. For fully loaded rural cells, the 16QAM modulation scheme with code rate of 7/8 cannot be supported. Also, it is noticed that, in urban zones, HSDPA mode can support 16QAM with code rate of 1/2 and QPSK modulation schemes when cells are not fully loaded. For fully loaded urban cells, only QPSK with code rate of 1/2 can be supported.

In Universal Mobile Telecommunication System (UMTS), the downlink capacity is limited by the base station transmission power. Therefore, power control plays an important role to minimize the transmitted power shared among unicast and multicast users within a cell. In Multimedia Broadcast/Multicast Service (MBMS), power control targets to the efficient utilization of radio and network resources. However, the expected high demand for such services stresses the need for an efficient scheme, capable of dynamically allocating radio resources to parallel MBMS sessions. This paper proposes a power control mechanism for efficient MBMS session assignment in next generation UMTS networks. The mechanism shares efficiently the available power resources of UMTS base stations to MBMS sessions running in the network. Furthermore, the mechanism is evaluated through several realistic scenarios and the results indicate the ability of the mechanism to utilize efficiently the radio resources and to ensure the service continuity when parallel MBMS services run in the network. Our approach is compared with current 3rd Generation Partnership Project (3GPP) approaches, such as these presented in TS 25.346 and in TR 25.922, in order to highlight the enhancements that it provides.

The IP Multimedia Subsystem (IMS) is one promising candidate for merging currently deployed circuit-switched and packet-switched voice and data networks into a service-based All-IP architecture. One requirement common to all of these Next Generation Network (NGN) architectures is seamless user mobility - a mandatory feature in order to match with the tremendous success of today's circuit-switched GSM voice networks. In addition most NGN architectures mandate the support for heterogeneous access technologies like WLAN, WiMAX, GPRS/EDGE, UMTS/HSDPA which raises the need for seamless vertical handover between these access technologies. Despite ongoing standardisation and technology developments like Generic Access Network (GAN), Voice Call Continuity (VCC) or Media Independent Handover (MIH, IEEE 802.21) we argue that there is currently no solution to enable seamless and application-transparent vertical handover in the IMS. In this paper, we review vertical handover standards for IMS and propose a novel vertical handover architecture which relies on geographical location and global network information as primary trigger or support for handover initiation. The underlying Session Initiation Protocol (SIP) notification framework - a Terminal-Centric IMS Location Enabler (LE) - is based on the key concept that location information is one specific kind of presence information which is optimally provisioned by mobile devices: the terminal knows best where it is located. The Location Enabler solicits notifications from the mobile device on specific events - e.g., entering or leaving specific geographical areas - thus dramatically reducing the amount of data transferred over the radio interface when compared to tracking or polling. The SIP registration and Re-Invite message flow is used to convey all handover-relevant information between the IMS core network and the mobile terminal. Using accurate access network measurement results the paper presents a performance estimation of the proposed vertical handover architecture with respect to handover duration and required handover area width at different velocities.

In this paper, we consider a method to enhance the throughput of HSDPA systems in the mixed traffic scenario. A channel-dependent adaptive delay barrier (DB) function is proposed to maximize throughput of best-effort (BE) traffic while satisfying the delay latency of voice over internet protocol (VoIP) service. Simulations show that the proposed channel-adaptive DB function raises the throughput of BE traffic service by 30% compared to the conventional scheme, without degrading the capacity of VoIP service over HSDPA system.

This paper explains how 3G high speed packet access (HSPA) works. High-speed packet access in both its flavours, HSPDA for the downlink and HSUPA for the uplink, is a hot topic in 3G. The real breakthrough has been achieved by dramatic improvements in the physical layer. This article explains what they are and how they lead to the kind of data rates needed to guarantee 3G a future in the evolution towards all-IP networks.

In this letter, we evaluate the capacity of voice over internet protocol (VoIP) services over high-speed downlink packet access (HS-DPA), in which frame-bundling (FB) is incorporated to reduce the effect of relatively large headers in the IP/UDP/RTP layers. Also, a modified proportional pair (PF) packet scheduler design supporting for VoIP service is provided. The main focus of this work is the effect of FB on system outage based on delay budget in radio access networks. Simulation results show that VoIP system performance with FB scheme is highly sensitive to delay budget. We also conclude that HSDPA is attractive for transmission of VoIP if compared to the circuit switched (CS) voice that is used in WCDMA (Release'99).

The parallel multichannel stop-and-wait (SAW) hybrid automatic repeat request (HARQ) mechanism is one of key technologies for high-speed downlink packet access in the wideband code division multiple access system. However, this parallel HARQ mechanism may encounter a serious stall problem, resulting from the error of the negative acknowledgement (NACK) changing to the acknowledgement (ACK) in the control channel. In the stall situation, the receiver waits for a packet that will be no longer be sent by the transmitter and stops delivering the medium access control (MAC) layer packets to the upper layer. The stall issue seriously degrades the quality of service for the high-speed mobile terminal owing to the high probability of NACK-to-ACK errors. In this paper, we present an analytical approach to compare three stall avoidance schemes: the timer-based, the window-based, and the indicator-based schemes. To this end, we first propose a new performance metric-gap processing time, which is defined as the duration for a non recoverable gap appearing in the MAC layer reordering buffer until it is recognized. Second, we derive the probability mass functions and the closed-form expressions for the average gap processing time of these three stall avoidance schemes. It will be shown that our analytical results match the simulations well. Further, by analysis, we demonstrate that the indicator-based stall avoidance scheme outperforms the timer-based and the window-based schemes. The developed analytical approaches can help determine a proper number of processes for the parallel SAW HARQ mechanisms. We also show that the analytical formulas can be used to design the number of acceptable fully loaded users for an admission control policy subject to the gap processing time constraint. In the future, our analysis can facilitate the MAC/radio link control (RLC) cross-layer design because the gap processing time in the MAC layer is closely related to the RLC timeout mechanism and the window size in the RLC retransmission mechanism

This paper describes network level simulation results for Enhanced UMTS. High-Speed Downlink Packet Access (HSDPA) enhances both the capacity and the peak rate of WCDMA-based systems. Link adaptation and Hybrid-Automatic Repeat reQuest (H-ARQ) are two key functions creating these enhancements. This paper considers the results of different aspects of the H-ARQ process. This process is considered from two viewpoints. The results are mainly gathered from the ns-2 based network level simulator Enhanced UMTS Radio Access Networks Extension (EURANE). This is a network level simulator with realistic traffic and user scenarios. Also results from a more fundamental analysis of H-ARQ characteristics based on link-level results will be included. In this more fundamental point of view, only the underlying channel conditions are used for a preliminary study of new ideas. The rounding down and delaying of the CQI reporting both have a significant impact on throughput and transfer delay of the HSDPA channel. The analysis of the link-level results provides a first insight how different parts of the WCDMA system interact with each other and impact the end-to-end performance as experienced by the user. Both viewpoints show that the H-ARQ functionality indeed enhances the capacity and peak rate of the WCDMA system.

Adaptive Modulation and Coding ( AMC ) has gained a lot of attentions in the research of High Speed Downlink Packet Access ( HSDPA ). The idea is to adapt the transmission to the fast changing channel conditions by the use of different Modulation and Coding Schemes ( MCS ). This paper presents an adaptive AMC algorithm and introduces a theoretical analysis model in order to to investigate its through put and Frame Error Rate ( FER ). Subject to the given FER target, our numerical and link level simulation results both show that our algorithm out performs other existing adaptive algorithms.

The author discusses various aspects of developments in the field of 3G communications and HSDPA, including: heterogeneous wireless communications, WiMAX and WLAN, mobile TV, health issues, location based services and e-commerce based services, spectrum licences, forums and industry alliances, the US market and industrial forecasts

The increasing demand for capacity in order to provide high data-rate multimedia services in wireless environments necessitates enhanced radio transmission techniques and network protocol functionality. Such techniques have to be added to already existing mobile cellular networks, e.g., as provided by Enhanced Data Rates for GSM Evolution (EDGE). For 3rd generation UMTS networks based on WCDMA, High Speed Downlink Packet Access (HSDPA) is being introduced to meet this demand and to improve spectral efficiency. This technique is based on well-known Link Adaptation (LA) by using various modulation and coding schemes and with this realising several different data rates for downlink transmission. Moreover, fast scheduling techniques based on shortened radio frames enable efficient and flexible sharing of the radio resources among different users and services. This article gives a detailed overview on the integration of HSDPA in UMTS networks and provides a detailed performance evaluation for a realistic scenario comprising a multi-cellular environment with various types of applications.

We present an analytic derivation of downlink dimensioning for a wireless network employing the "high speed downlink packet access" (HSDPA) standard, currently being developed by the 3/sup rd/ Generation Partnership Project (3GPP) as part of the next stage in the evolution of the WCDMA standard (see Frenger, P. et al., "Performance Comparison of HARQ with Chase Combining and Incremental Redundancy for HSDPA", http://www.3gpp.org; Moulsley, T. J., 3G Mobile Commun. Technologies, IEE Conf. Publication No. 477, 2001). We determine the maximum possible cell radius such that the probability of outage, P/sub out/, at the cell's "worst" location does not exceed a preset value under full load conditions. The results are presented in the form of curves obtained by numerical integration of integral expressions. The results can be used, for instance, to find the increase in cell radius achievable by a certain reduction in the value of the signal-to-interference-plus-noise ratio (SINR) threshold used to define outage.

In this paper, the theoretical performance of cellular systems with different types of link adaptation is analyzed. A general link and system performance analysis framework is developed to enable the system-level performance characteristics of the various link adaptation strategies to be studied and compared. More specifically, this framework is used to compare the downlink performance of fully loaded cellular systems with fixed power and modulation/coding, adaptive modulation/coding (AMC), adaptive power allocation (APA) with system-level AMC, and water-filling (WF). Performance is studied first for idealized methods, and then for cases where some practical constraints are imposed. Finally, a hybrid link adaptation scheme is introduced and studied. The hybrid scheme is shown to overcome most of the performance loss caused by the practical constraints. Moreover, the hybrid scheme, as opposed to WF, enables the system to be tuned to meet the most important performance objective for the system under consideration, such as coverage reliability, capacity, or data rate distribution. The algorithms and the framework presented in this paper can be used to improve the link adaptation performance of modern cellular systems such as HSDPA.

Third Generation Partnership Project (3GPP) specification TR 25.950 proposed high-speed downlink packet access for the Universal Mobile Telecommunication System (UMTS). In this mechanism, an active set of cells is defined for every user equipment (UE) communication session. The cell with the best wireless link quality (called the serving cell) in the active set is selected for communication with the UE. When the wireless link quality of the old serving cell degrades below some threshold, a new serving cell in the active set is selected to continue the communication session. Our previous work proposed a high-speed downlink packet access (HSDPA) overflow control scheme with four frame synchronization algorithms to switch the serving cell, and formally proved the correctness of the scheme. We propose an analytic model to investigate the performance of these frame synchronization algorithms, and show how the user movement patterns affect the control message delivery costs of these algorithms.

Third Generation Partnership Project (3GPP) produced the first full version of the WCDMA standard at the end of 1999. This release, called Release'99, contains all the necessary elements to meet the requirements for IMT-2000 technologies, including 2 Mbps data rate with variable bit-rate capability, support of multi-service, QoS differentiation and efficient packet data. The Release 5 specifications were created in March 2002 and they contain downlink packet data operation enhancement, under the title high speed downlink packet access (HSDPA). HSDPA utilizes Hybrid ARQ and higher order modulation for improving data-spectral efficiency and for pushing bit rates beyond 10 Mbps. The further 3GPP releases will study the enhancements of packet-data performance in uplink. Other important features in future 3GPP releases include advanced antenna technologies and WCDMA standard for new spectrum allocations. The paper describes the main solutions of 3GPP WCDMA standard in more detail. Copyright © 2003 John Wiley & Sons, Ltd.