HSPA+ Evolution to Release 12

A large number of phone calls and data services will take place in indoor environments. In Long Term Evolution (LTE), femtocell, as a home base station for indoor coverage extension and wideband data service, has recently gained significant interests from operators and consumers. Since femtocell is frequently turned on and off by a personal owner, not by a network operator, one of the key issues is that femtocell should be identified autonomously without system information to support handover from macrocell to femtocell. In this paper, we propose a dynamic reservation scheme of Physical Cell Identities (PCI) for 3GPP LTE femtocell systems. There are several reserving types, and each type reserves a different number of PCIs for femtocell. The transition among the types depends on the deployed number of femtocells, or the number of PCI confusion events. Accordingly, flexible use of PCIs can decrease PCI confusion. This reduces searching time for femtocell, and it is helpful for the quick handover from macrocell to femtocell. Simulation results show that our proposed scheme re- duces average delay for identifying detected cells, and increases network capacity within equal delay constraints. The 3rd Generation Partnership Project (3GPP) is work- ing on the standardization of asynchronous communication systems. This technology is being enhanced gradually en- suring higher user data rate, bigger system capacity, and lower cost. The wideband CDMA (WCDMA) system is standardized with 3GPP release 99/4 which is being de- ployed in the world. Release 5 is related to High Speed Downlink Packet Access (HSDPA), and it improves the downlink packet transmission speed theoretically up to 14.4 Mbps. High Speed Uplink Packet Access (HSUPA) is enhanced up to 5.76 Mbps in uplink, and it is standardized with the Release 6. We simply mention both HSDPA and HSUPA as High Speed Packet Access (HSPA). In release 7, High Speed Packet Access Evolution (eHSPA, HSPA+) is standardized. eHSPA is based on the HSPA network with a simple upgrade, and it supports more bandwidth efficiency and lower latency. The maximum data rate is 28.8 Mbps in downlink and 11.5 Mbps in uplink (1). How- ever, users still require further system improvements. The technology is dramatically enhanced in release 8, where the standard of Long Term Evolution (LTE) is currently being established. The main objectives of LTE are higher data rates, lower latency, increased capacity, enhanced coverage, and an optimized system for the packet switching network (2). LTE also considers a femtocell, which is referred to as a home base station for an indoor coverage extension and overall network performance enhancement (3). Recently, LTE-Advanced standard targeting of 1Gbps for low mobil- ity is being discussed in release 9. We look into general features and requirements of fem- tocells. Important issues related to access control are de- scribed, followed by our contributions and organization of the paper.

The amount of mobile video streaming traffic is rapidly growing and a potential candidate to reduce the load on the content delivery infrastructure is given by the peer-to-peer (P2P) paradigm. One might argue about the adequacy of P2P in this mobile context, yet, it has already become reality. Popular P2P streaming networks like SopCast or TVU networks have recently deployed their apps for mobile devices. In this paper the current state of a location-aware measurement framework is presented, which was mainly developed to evaluate P2P systems in cellular networks. We use our generic framework to present the first measurement study that investigates the behavior of the popular P2P video streaming application SopCast when it is operating in a UMTS High Speed Packet Access (HSPA) network and compare the results with reference Ethernet measurements. The aim of this study is to discover the impact of cellular networks and user mobility on the performance of such P2P applications. In particular we could observe that as consequence some of the drawbacks are characterized by poor connectivity among peers and negligible upload contributions.

In this paper, we analyze the capacity of Circuit Switched Voice over High Speed Packet Access (HSPA) (CSoHS), using a Release 7 HSPA system that supports Continuous Packet Connectivity (CPC). On the Downlink (DL), we modeled the power consumption of the Fractional Dedicated Physical Channel (F-DPCH) and the Enhanced DCH Hybrid ARQ Indicator Channel (E-HICH). On the uplink (UL), we modeled the overhead channels, High Speed Dedicated Physical Control Channel (HS-DPCCH) and Enhanced DCH Dedicated Physical Control Channel (E-DPCCH). Our results show voice capacity gains that are achievable with CPC. We also show the gains in downlink voice capacity that are achievable by using the MAC-segmentation feature, introduced in Release 7.

In this paper an innovative Radio Resource Management (RRM) algorithm is proposed with the purpose of increasing High Speed Packet Access (HSPA) performances, in terms of system capacity and service quality, when the Multimedia Broadcast Multicast Services (MBMS) is supplied. The proposed RRM algorithm exploits channel quality indications to set up point-to-multipoint connections to subgroups of multicast users and to select the proper modulation and coding schemes on the downlink. The number of subgroups is determined through an optimization technique that also takes into account the user satisfaction. An exhaustive simulation campaign is conducted to compare the proposed algorithm with the most promising approaches in the literature. Comparisons aim to assess the capability of the proposed RRM algorithm to efficiently manage group oriented services by providing an increment in terms of user satisfaction.

Nowadays you can see everyone holding mobile phones on the street, used to be with only purely voice service till now, as the progress of the technology, function of wireless internet surfing is more and more valued. Whether video call, on-line browsing, or navigation is to provide consumer a multiple service. To fulfill most users’ request, high-speed downloading of 3G broadband system is needed. Telecom Operators start to create mass HSPA (High Speed Packet Access) system in 2009, meaning HSDPA (High Speed Downlink Packet Access) could reach 14.4Mbps and HSUPA (High Speed Uplink Packet Access) could reach 2Mbps. In order to fulfill this mass transportation, Telecom Operator not only has to upgrade the software and hardware of base stations (aka. Node B), the flow of physical circuit’s transmission also has to reach certain bandwidth. Considering investment cost and quality of service, fixed Telecom operators has take a new generation NG-SDH (Next Generation-Synchronous Digital Hierarchy). Using Ethernet to provide physical transmission of wireless internet browsing. This thesis is mainly discussing new generation Ethernet NG-SDH’s usage, while current base station using physical fiber circuit to provide transmission internet service quality. Through the result if the experiment, we will have a better reference for transmission service quality and solution when future operators planning transmission of HSPA+, 4G LTE (Long Term Evolution).

Long Term Evolution(LTE) 시스템은 멀티미디어 서비스와 같은 다양한 서비스를 이동 사용자에게 제공할 수 있다. 실제로 HSPA+(High Speed Packet Access plus)는 다운링크의 비트 율(bit rate)을 크게 향상 시켰으나, 다양한 멀티미디어 서비스에서 요구하는 서비스 품질을 어떻게 만족시킬 것인가에 대한 연구는 매우 미비한 상태이다. 본 논문에서는 proportional fair(PF) 알고리즘을 기반으로 하여 LTE를 위한 효율적인 패킷 스케쥴링 알고리즘을 제안하였다. 제안된 알고리즘에서는 패킷 스케쥴링을 할 때 패킷의 우선순위를 결정하는 가장 중요한 요소인 트래픽 클래스의 가중치와 순간 사용자 데이터 전송율을 최적화 하였다. 또한 다중 셀(multi-cell) 환경에서 LTE를 통해서 사용자에게 전송되는 멀티미디어 트래픽을 시뮬레이션 함으로써 제안된 알고리즘의 성능이 향상되었음을 보였다. The Long Term Evolution (LTE) system is already able to provide a background of variety services for mobile users with multimedia services such as audio, video, and data. In fact, the High Speed Packet Access plus (HSPA+) solution can greatly enhance bit rates on down-link. However, the supporting for multimedia applications with different QoS (Quality of Service) requirements is not devised yet. Hence, in this paper we propose an effective packet scheduling algorithm based on Proportional Fairness (PF) scheduling algorithms for the LTE. In this proposed packet scheduling scheme, we optimized instantaneous user data rates and the traffic class weight which prioritize user's packets. Finally, we evaluated and showed the performance of the proposed scheduling algorithm through simulations of multimedia traffics being transmitted to users over LTE links in a multi-cell environment.

무선 접속을 통한 인터넷 서비스가 보편화된 최근 사람이 서비스를 이용하는 과정에서 실제로 느끼는 품질인 사용자 체감 품질(QoE; Quality of Experience)의 중요성이 더욱 강조되고 있는데 사용자 체감 품질은 서비스 품질 (QoS; Quality of Service)와 같이 객관적인 수치화가 불가능하다는 특징이 있다. 유선과는 달리 무선 접속을 통해서 제공되는 IP 서비스는 매우 많은 요인에 의해서 사용자 체감 품질이 영향을 받을 수 있다. 따라서 본 논문에서는 대표적인 무선 접속 서비스인 HSPA (High Speed Packet Access)를 통해서 음성 서비스가 제공될 때 측정 가능한 품질지표를 선정하고 이들에 대한 실측값을 통계적으로 분석하여 서비스 품질과 사용자 체감 품질 지표와의 상관관계를 밝히고자 한다. 분석 결과 RSSI (Received Signal Strength Indicator)와 전송 지연의 상관관계가 매우 높고 그에 이어 전송 지연과 MOS (Mean Opinion Score)와 매우 높은 상관관계를 가짐을 알 수 있었다. As internet services are being provided through a wireless access, the importance of quality of experience (QoE) is stressed that is defined as the quality that indicates user's actual feeling when a service is provided. Unlike quality of service (QoS) that can be expressed as a numerical value, it is difficult to represent QoE in an objective way. If an internet service is serviced over a wireless channel, its QoE can be affected by a number of factors such as fading, mobility and so on. This paper, therefore, attempts to specify the relationship between QoE and QoS by conducting practical measurements for the voice service through 3G high speed packet access (HSPA) access network. Analysing the measured results, it has been shown that received signal strength indicator (RSSI) has a great influence on mean opinion score (MOS) through transmission delay.

In this paper, we consider a low-complexity multiuser detection for downlink of high speed packet access (HSPA) of universal mobile telecommunications system (UMTS). Instead of attempting to perform maximum likelihood (ML) detection of all users in multiple cells, which is impractical for battery powered mobile receiver, we utilize interference cancelled chips obtained from iterative linear minimum mean square error (LMMSE) estimation to perform a near ML detection in a reduced dimensional system. As a result, the worst case complexity of the detection process, achieved by the closest lattice point search (CLPS), is bounded to a controllable level irrespective of multipath spans. Furthermore, by exploiting the LMMSE estimate in tightening the hypersphere condition of the CLPS algorithm so called sphere decoding, we achieve significant improvement in search complexity. From simulations on realistic downlink communication scenario in HSPA systems, we show that the proposed method offers substantial performance gain over conventional receiver algorithms with reasonable complexity.

The reliability of packet data transmissions under large scale fading is a key issue in wireless mobile networks and has been studied by many researchers, but mostly through simulation and analytical modelling. In this research paper, a realistic methodological approach has been employed to better characterize and quantify the impact of the shadow fading effect on High Speed Packet Access (HSPA) network reliability in different suburban environment scenarios. In this regard, radio frequency signal propagation measurement was first conducted using mobile drive test investigation procedure in hilly, open and residential terrains. By using regression analysis on the RF field data, the long term attenuation pattern of the measured signal power was obtained and the power decaying propagation exponent varied between 2.50 and 3.03. From the characterized pathloss model parameters obtained in the measurements, the HSPA link reliability has been evaluated using the Packet Error rate outage (PE-Outage) probability analysis. Furthermore, the impact of signal power variability on the user equipment terminal has been quantified with and without shadow fading. The results showed that shadow fading can have a significant impact on network reliability. The simplified approach adopted can be useful for a methodical evaluation of system reliability in similar mobile broadband networks deployed in more challenging environments.

In this paper, we address challenges to packet switched video telephony (PSVT) in 3G wireless networks such as High Speed Packet Access (HSPA), and propose a technique which can improve PSVT service in 3G wireless networks. In HSPA, temporary decrease in available bandwidth can occur based on the user’s location in the cell and/or system loading conditions. This can result in significant increase in observed packet latency, potentially resulting in dropped packets at the receiver. To overcome this problem we describe a feedback based rate adaptation scheme. The proposed scheme is capable of adapting the video encoder bitrate to the varying channel bandwidth and hence minimize the packet latency. The novelty of our proposed approach is that the algorithm matches encoded source rate to varying channel conditions without making any piecewise constant bitrate (CBR) assumptions on the channel. In the proposed scheme the observed throughput is monitored on the uplink (i.e. from sending mobile to the network) and on the downlink (i.e. network to the receiving mobile). The desired target data rate is determined based on these observed throughput. Based on the source variability and the desired target data rate, the algorithm controls the encoding time and packet size (e.g. bytes) of video frames scheduled for transmission. We present simulation results of the proposed approach, based on approved specifications and common simulation conditions adopted in 3GPP and ITU. We show that the one-way delay can be significantly reduced by providing timely feedback of observed throughput from receiving mobile to the sending mobile. By using such a feedback message once every 200 ms, we show that 95 percentile of the packets were delivered with a one-way delay under 250 ms. We also show that our proposed algorithm is capable of graceful degradation based on available system resources and user’s location in the cell.

This paper outlines key aspects that operators need to consider when expanding their radio access infrastructure to get a cost efficient production of wireless services. Two promising expansion paths are analyzed with respect to the achievable area throughput for an urban scenario. The first is considering a cellular evolution based on high speed packet access (HSPA) with multiple input multiple output (MIMO) technology in macro base stations. The other is a multi radio access (multi-access) environment where a HSPA macrocell layer without MIMO is complemented with IEEE 802.11a wireless local area network (WLAN) access points. When accounting for the difference in total cost for complementary base stations, the cellular evolution supports a higher average area throughput in downlink for low and moderate hot spot densities. The advantage decreases with macro base station site density so for higher hot spot and macrocell site densities the multi-access system is more favourable. For uplink the multi-access network in general supports higher capacity thanks to that the cellular evolution is limited by penetration losses for indoor users. Thus, depending on how densely an existing macrocell network is deployed and the targeted capacity in downlink and uplink, different expansion paths would bring the lowest cost of infrastructure.

To address future demand for improved services the next generation mobile systems will be compatible and interoperable with IPv6 and with various access technologies such as 802. llx. Discussion in the literature is currently as to whether the recently developed High Speed Packet Access (HSPA) or the developing Long Term Evaluation (LTE) technology is appropriate for the next generation mobile system. However, the HSPA and the LTE technologies require enhancements to provide ubiquitous data services. Hybrid network interworking of 3G/WLAN is capable of supporting ubiquitous data services and improved data rates in WLAN hotspots. This paper provides the results of a performance analysis of two potential 3G/WLAN integration schemes: tight and loose coupling. Mobile IP is used as a mobility management scheme and EAP-AKA for common authentication.

By employing Bayesian neural network, a new QoS prediction algorithm for high speed packet access network has been developed. Network performances are evaluated based on a well developed call admission control scheme, namely the tri-threshold bandwidth reservation scheme. The algorithm helps to improve the resource management, thus saving the cost and bandwidth.

Selective per antenna rate control (S-PARC) technique has been decided to be deployed in time division-synchronous code division multiple access (TD-SCDMA) high speed packet access plus (HSPA+) system. In this paper, we propose an enhanced data stream selection algorithm for the proposal of S-PARC to improve Node B average throughput and initial block error rate (BLER) by pre-processing signal to interference plus noise ratio (SINR). The new algorithm considers the impact of channel fluctuation, Node B average initial BLER and continue scheduling of the same UE. It is shown that the proposed scheme can achieve remarkable improvement of system performance, especially when UEis under high speed mode, and it also has advantages in the following ways: little modification for current specification, low computational complexity and no additional controlling signals.

The power consumption of wireless access networks will become an important issue in the coming years. In this study, the power consumption of base stations for mobile WiMAX (Worldwide Interoperability for Microwave Access), fixed WiMAX, UMTS (Universal Mobile Telecommunications System), HSPA (High-Speed Packet Access) and LTE (Long-Term Evolution) is modelled and related to the coverage. A new metric, the power consumption per covered area PC(area), is introduced, to compare the energy efficiency of the considered technologies for a basic reference configuration and a future extended configuration, which makes use of novel Multiple Input Multiple Output (MIMO) technology. The introduction of MIMO has a positive influence on the energy efficiency: for example, for a 4 x 4 MIMO system, PC(area) decreases with 63% for mobile WiMAX and with 50% for HSPA and LTE, compared to a Single Input Single Ouptut (SISO) system. However, a higher MIMO array size (i.e. a higher number of transmitting and receiving antennas) does not always result in a higher energy efficiency gain.