WCDMA in Malaysia

Wideband Code Division Multiple Access (WCDMA) A 3G highspeed digital data service provided by cellular carriers that use the time division multiplexing (TDMA) or GSM technology worldwide, including AT&T (formerly Cingular) and T-Mobile in the U.S. WCDMA works on WCDMA cell phones as well as laptops and portable devices with WCDMA modems [1]. Users have typically experienced downstream data rates up to 400 Kbps [1]. WCDMA has been used in the Japanese Freedom of Mobile Multimedia Access (FOMA) system and in the Universal Mobile Telecommunications System (UMTS); a third generation follow-on to the 2G GSM networks deployed worldwide [1]. Although TDMA and GSM carriers both use TDMA modulation, WCDMA stems from CDMA. Part of the 3GPP initiative, the International Telecommunication Union (ITU) refers to WCDMA as the Direct Sequence (DS) interface within the IMT-2000 global 3G standards [1]

An Adaptive Soft Handover Scheme Using Fuzzy Load Balancing for WCDMA Systems

In cellular systems, user distribution variations can cause load imbalance between cells. Embedding a load balancing strategy within the handover scheme means that ensuing traffic congestion can be alleviated by dynamically reallocating load between neighbouring cells. An adaptive soft handover scheme for multimedia cellular communication systems is proposed in this paper, that considers both the cell load factors as well as the pilot channel signal-to-interference-and-noise-ratio (SINR) for soft handovers. By using fuzzy principles, the soft handover thresholds and time hysteresis are adapted dependent upon the loads of the neighbouring cells. Simulation results show that the new algorithm provides improved system performance in terms of a more evenly distributed load, lower blocking probabilities and higher throughput

The 3G standard setting strategy and indigenous innovation policy in China is TD-SCDMA a flagship?

In the time of “network economy”, industries and the public have stressed several “battles for dominance” between two or more rival technologies, often involving well-known firms operating in highly visible industries. In this paper, we are going to focus on the Chinese self-developed standard TD-SCDMA to perceive the implication and target of the nation’s policy and strategy. The motivation of the research starts from the interesting fact we observed: TD-SCDMA is named as the Chinese made standard, however the Chinese hold core patent technology is still about 7%, while most of the rest part is still taken by other foreign companies. The “faultage” between the small share reality and a self made standard sweet dream implies a well plotted strategy. In order to understand it, we firstly raise the question of why the Chinese government postpones the 3G decision again and again. Then we go further to probe why the standard-setting of TD-SCDMA has aroused wide attention as a strategic tool to fulfill “indigenous innovation”, and finally becomes part of national science and technology policy to increase international competitiveness? We are going to use economics theories to understand the essence of the creation of TD-SCDMA, and its relation to China’s interests.3G, standard, innovation, China

Chinese Experience with Global G3 Standard-Setting

China’s growth strategy as set out in the 11th 5-year plan in 2005 called for upgrading of product quality, the development of an innovation society, and reduced reliance on foreign intellectual property with high license fees. Consistent with this policy, China has been involved in recent years with the development of a Chinese standard in third generation (3G) mobile phone technology, both in negotiating the standard and seeing it through to commercialization. This is the first case of a developing country both originating and successfully negotiating a telecommunications standard and this experience raises issues for China’s future development strategy based on product and process upgrading in manufacturing. We argue that while precedent setting from an international negotiating point of view, the experience has thus far is unproven commercially. But the lessons learned will benefit future related efforts in follow-on technologies if similar Chinese efforts are made.This paper documents Chinese standard-setting efforts from proposal submission to ITU to the current large-scale trial network deployment in China and overseas trial networks deployment. We discuss the underlying objectives for this initiative, evaluate its effectiveness, and assess its broader implications for Chinese development policy.

Communication Standards Adoption in Developing Economies: Issues and Options for India

Given the importance of communications in todays world, its spread in developing economies is critical for their development. Emergence of standards reduces market and technological uncertainty and lays the foundation for market creation and enhances the diffusion of communication technologies partly through the advantages associated with network and scale economies. Standardisation has also become important with the rise in cross-fertilisation between information technology (IT) and other technologies, especially in communications. Under these circumstances, strategic implications of IT standardisation are huge because standards can determine the growth potential of individual firms, affect the competitive advantage of nations and even development of technologies and their diffusion. Policies for standards adoption have been used world-wide to facilitate the diffusion of communications technologies, acquire a larger market share of the global telecom market, build technological capabilities. The paper reviews various approaches to communications standard adoption as well as the experiences of other countries. These approaches and experiences and the associated market and regulatory failures are evaluated in the context of the current Indian situation. This evaluation suggests that a standards neutral policy is desirable for India.

Real Options: Strategic Technology Migration Options in Wireless Industry

The major US wireless operators already have announced their plans for evolution of their networks, but some uncertainties remain, such as emergence of new technologies (WiMAX and WLAN) and consolidation among operators (AT&T Mobile and Sprint Nextel). The paper proposes a real option based model for technology decisions and applies it to the US wireless industry as a case study. We also discuss what decisions are made, what the outcomes are, and how the options model is validated. The preliminary results show that the evolution of wireless network technologies between generations (intergenerations migration scenario) is desirable (a positive net option value), but not desirable (a negative net option value) within generations (intra-generation migration scenario)

Improved decoder metrics for DS-CDMA in practical 3G systems

While 4G mobile networks have been deployed since 2008. In several of the more developed markets, 3G mobile networks are still growing with 3G having the largest market -in terms of number of users- by 2019. 3G networks are based on Direct- Sequence Code-Division Multiple-Access (DS-CDMA). DS-CDMA suffers mainly from the Multiple Access Interference (MAI) and fading. Multi-User Detectors (MUDs) and Error Correcting Codes (ECCs) are the primary means to combat MAI and fading. MUDs, however, suffer from high complexity, including most of sub-optimal algorithms. Hence, most commercial implementations still use conventional single-user matched filter detectors. This thesis proposes improved channel decoder metrics for enhancing uplink performance in 3G systems. The basic idea is to model the MAI as conditionally Gaussian, instead of Gaussian, conditioned on the users’ cross-correlations and/or the channel fading coefficients. The conditioning implies a time-dependent variance that provides enhanced reliability estimates at the decoder inputs. We derive improved log-likelihood ratios (ILLRs) for bit- and chip- asynchronous multipath fading channels. We show that while utilizing knowledge of all users’ code sequences for the ILLR metric is very complicated in chip-asynchronous reception, a simplified expression relying on truncated group delay results in negligible performance loss. We also derive an expression for the error probability using the standard Gaussian approximation for asynchronous channels for the widely used raised cosine pule shaping. Our study framework considers practical 3G systems, with finite interleaving, correlated multipath fading channel models, practical pulse shaping, and system parameters obtained from CDMA2000 standard. Our results show that for the fully practical cellular uplink channel, the performance advantage due to ILLRs is significant and approaches 3 dB

Chinese cellular telecommunications in the past and the 21st century

Cellular telecommunication technology is one of the hottest topics of the last two decades. The annual rate of user growth is more than 30 percent. It began with the first generation (1G) networks and bloomed with second generation (2G) of cellular technologies. New third generation cellular (3G) technologies aim at offering high-speed, superior-quality information service to mobile subscribers. [2] The Chinese cellular market is developing with unbelievable speed. China launched its first cellular network in 1987. At the end of 2002, it was the biggest wireless market in the world, with more than 200 million subscribers. [56] Technologies used in the migration from the 2G networks to the 3G networks are referred to as 2.5 generation or 2.5G. It is no doubt that the 3G pattern selected in China will deeply affect the competition among the 3G technologies. This thesis will forecast the 3G systems to be selected for use in China. It will begin with the 1G and 2G networks and then look into the 2.5 G and the 3G cellular telecommunication technologies in more detail. Analysis the history, culture and business conditions in China will follow. Finally, this paper will make a prediction of the principal Chinese 3G technologies that will be chosen based on analyzing concrete information. An examination of other Asia markets, such as the 3G markets in Japan, and South Korea will be included. The conclusion of this thesis is that WCDMA (Wideband Code Division Multiple Access), a 3G technology that is developed and supported by European telecommunication manufacturers, will take the lion\u27s share of the Chinese 3G market, about 65% to 70%. Another technology, CDMA2000, will take more than 20% of the Chinese 3G market share. There is also a Chinese oriented 3G technology named TD-SCDMA (Time Division Synchronous Code Division Multiple Access). With the Chinese government\u27s support, it will collect the remaining 10% to 15% market share

Numerical Implementation of Representative Mobile Phone Models for Epidemiological Studies

This paper describes an implementation method and the results of numerical mobile phone models representing real phone models that have been released on the Korean market since 2002. The aim is to estimate the electromagnetic absorption in the human brain for casecontrol studies to investigate health risks related to mobile phone use. Specific absorption rate (SAR) compliance test reports about commercial phone models were collected and classified in terms of elements such as the external body shape, the antenna, and the frequency band. The design criteria of a numerical phone model representing each type of phone group are as follows. The outer dimensions of the phone body are equal to the average dimensions of all commercial models with the same shape. The distance and direction of the maximum SAR from the earpiece and the area above –3 dB of the maximum SAR are fitted to achieve the average obtained by measuring the SAR distributions of the corresponding commercial models in a flat phantom. Spatial peak 1-g SAR values in the cheek and tilt positions against the specific anthropomorphic mannequin phantom agree with average data on all of the same type of commercial models. Second criterion was applied to only a few types of models because not many commercial models were available. The results show that, with the exception of one model, the implemented numerical phone models meet criteria within 30%