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1.
《Telecommunications Policy》2006,30(8-9):424-444
This paper focuses on the question of which broadband technologies that are currently available (and/or under development) enable evolutionary paths for broadband (symmetrical bandwidth of 10 Mbps1) deployment in the local loop, leaving options open for new developments. The paper is relevant to policymakers and telecommunication operators who are faced with emerging technologies and who need to make short-term decisions about upgrading networks under risk and uncertainty. The concept of evolutionary paths and the advantages involved, such as smaller and more flexible investments and an increased adaptability to market developments, are addressed. Several wired and wireless transmission media are discussed on the basis of criteria like network capacity, reach, compatibility, standardization, maturity and technical and geographical scalability. Broadband technologies like ADSL2+, Etherloop, EFMC, CMTS+, Narad networks; EttH, EPON, APON, Optical Ethernet, LMDS, MMDS, FSO and HFR are assessed on the basis of these criteria. Starting from this assessment, migration paths for copper, cable and wireless technologies are presented and discussed.  相似文献   

2.
《Telecommunications Policy》2006,30(5-6):297-313
Xiaolingtong (XLT), a new type of mobile phone system based on PHS technology for wireless access of fixed-line telephone networks, has grown very rapidly in China. However, there are many doubts about the future of XLT once 3G (the third generation of mobile communication) is finally employed. This paper proposes a theoretical framework to assess and compare XLT and 3G from four perspectives: technology, market demand, business models and government policy. It concludes that XLT and 3G will coexist with existing 2G/2.5G mobile communication networks for a considerable period of time. With service collaboration and integration, the coexistence of both of these technologies can enhance China's mobile communication infrastructure and support the growth of mobile commerce.  相似文献   

3.
《Telecommunications Policy》2006,30(5-6):332-344
Several statutory restrictions have recently been lifted on the use of Voice over Internet Protocol (VoIP) in South Africa. Previously, VoIP could only be utilised by the incumbent telecommunications operator, Telkom, the Second National Operator (SNO) and under serviced area licensees (USALs). This means new opportunities and cost savings for both network service providers and consumers. However, in rural and remote regions, further liberalisation is required so that service providers can take advantage of wireless technologies to provide connectivity in these areas. This paper discusses the legislative environment in South Africa and around the world with respect to VoIP and Wireless Fidelity (WiFi). In addition, examples are provided of how these technologies have been combined to provide last mile solutions around the world and particularly in South Africa. The paper concludes that further liberalisation in the telecommunications environment in South Africa is required if the goal of providing affordable access in rural areas is to be attained. Specifically, it is recommended that wireless technologies be deregulated since the combination of VoIP and WiFi may benefit rural areas. Also, the paper finds that USALs may not be the right model for underserviced areas in South Africa. Lastly, it is apparent that applications drive development and dictate which technologies are relevant for rural areas.  相似文献   

4.
Even before the International Telecommunication Union (“ITU”) reaches consensus on spectrum allocations for fifth generation wireless technologies (“5G”), commercial ventures scramble to offer new equipment and services. Expediting 5G wireless service can benefit consumers and businesses at the risk of stressing the traditional process of spectrum planning that combines study, dialogue and consensus building at ITU conferences.This paper explains why most nations refused to endorse key United States 5G spectrum allocation proposals at the ITU’s, 2015 World Radio Conference. U.S. representatives underestimated the time needed for consensus building, despite increasing demand for wireless video and the evolving Internet of Things. Other contributing factors include U.S. support for treating spectrum like property, use of “incentive auctions” to clear broadcast television spectrum with unprecedented speed and enough existing wireless spectrum allocations in most nations.The paper concludes that the U.S. cannot expect faster frequency reallocations, particularly when it and other nations pursue matters having little to do with spectrum optimization. The paper offers recommendations on best practices for improving the consensus building process.  相似文献   

5.
In recent years, significant attention has been directed toward the fifth generation of wireless broadband connectivity known as ‘5G’, currently being deployed by Mobile Network Operators. Surprisingly, there has been considerably less attention paid to ‘Wi-Fi 6’, the new IEEE 802.1ax standard in the family of Wireless Local Area Network technologies with features targeting private, edge-networks. This paper revisits the suitability of cellular and Wi-Fi in delivering high-speed wireless Internet connectivity. Both technologies aspire to deliver significantly enhanced performance, enabling each to deliver much faster wireless broadband connectivity, and provide further support for the Internet of Things and Machine-to-Machine communications, positioning the two technologies as technical substitutes in many usage scenarios. We conclude that both are likely to play important roles in the future, and simultaneously serve as competitors and complements. We anticipate that 5G will remain the preferred technology for wide-area coverage, while Wi-Fi 6 will remain the preferred technology for indoor use, thanks to its much lower deployment costs. However, the traditional boundaries that differentiated earlier generations of cellular and Wi-Fi are blurring. Proponents of one technology may argue for the benefits of their chosen technology displacing the other, requesting regulatory policies that would serve to tilt the marketplace in their favour. We believe such efforts need to be resisted, and that both technologies have important roles to play in the marketplace, based on the needs of heterogeneous use cases. Both technologies should contribute to achieving the goal of providing affordable, reliable, and ubiquitously available high-capacity wireless broadband connectivity.  相似文献   

6.
本文通过灰色关联分析和VECM深入研究了我国固定资产总投资、各个产业投资与GDP以及各产业产值的关系。结果发现我国固定资产投资对经济增长的影响很大,第三产业投资对第一产业和第三产业产值的关联程度很大;而第三产业产值对各业投资的依存程度较强。固定资产投资是经济增长的格兰杰原因,经济增长却不是固定资产投资的格兰杰原因。我国经济应该在增强自身内生发展能力下功夫。  相似文献   

7.
《Telecommunications Policy》2007,31(3-4):179-196
Number portability (NP) is considered by the European Commission as a key measure for promoting competition within the telecom sector especially regarding network access infrastructure. However, NP requires several modifications to the network architecture and to the business processes of each operator that, depending on network size, may result in a significant financial cost. This is true for fixed networks in particular. Given the requirement for such an investment, National Regulatory Authorities (NRAs) desire a clear picture on what to expect, in terms of progress in access competition, when introducing fixed NP in their respective markets. The paper approaches this question by correlating several fixed telephony market indices related to access competition to the degree of success of fixed NP. Relevant analysis based on European Union member states’ data indicates that fixed NP does not significantly contribute to local loop unbundling (LLU) adoption in markets where there are other access technologies available. In these markets, access competition via these other technologies and fixed NP initially achieve similar penetration rates. Consequently, when access competition exceeds a certain threshold and given a reasonable pricing regime then fixed NP is further boosted to include broadband connections based on several broadband technologies/methodologies such as LLU and cable as well as existing narrowband access technologies (e.g. narrowband cable connections). In markets where LLU is the only alternative for access then the rate of Fixed NP adoption is directly correlated with the success of LLU. Consequently, these conclusions are considered within a high-level stepwise approach for NP implementation, which is based on the experience acquired from the respective Greek national project.  相似文献   

8.
Next generation access networks are expected to bring ubiquitous broadband access and have attracted interest of municipal governments. This paper investigates the support by municipal authorities for the rollout of such a city-wide wireless broadband access network. Different business cases for 3G and WiFi operators are developed and it is indicated how to model the specificities for commercial versus public players. Furthermore, a game theoretic approach is used to investigate the investment options of the municipal player. It is shown that a partnership between a commercial and public player is the most likely investment strategy. However, bringing more players into the competitive environment reduces the intention of the commercial partner to engage in the public–private partnership (PPP).  相似文献   

9.
A number of countries around the world are trying to promote competition at the local loop as demand for higher bandwidth to the home increases. Different technologies (xDSL, cable modems, and wireless local loop) offer alternative solutions and the issue for regulators is to design a framework that promotes competition and investment. Regulators can promote competition in a number of ways, but two “pure” strategies are services and infrastructure competition. This paper models the regulator and incumbent–entrant interactions explicitly in order to understand how the structure of the voice services might evolve under different regulatory frameworks. Our analysis suggests that a “mix” of infrastructure and service competition like the one promoted in Netherlands, stimulates investment by incumbents and entrants alike and offers better consumer benefits. The message for policy makers is that the introduction of “sunset clauses” provides new entrants with strong incentives to invest while allowing them to enter in service competition and to acquire important knowledge about their new market.  相似文献   

10.
Since the late 1980s, technological advances and policy reforms have created new opportunities for private-sector investment in India’s seed and agricultural biotechnology industries. These changes have had a significant impact on cotton yields and output in India, but less so for rice and wheat—the country’s main cereal staples—for which yield growth rates are tending toward stagnation. This analysis examines the structures of these industries, their potential effects on competition and innovation, and the policies that may improve both industry performance and the delivery of new productivity-enhancing technologies to India’s cereal production systems. Our findings suggest that more substantive policy reforms are needed to encourage further innovation, reduce regulatory uncertainty, and encourage firm- and industry-level growth, while continued public spending on agricultural research is needed to support technological change.  相似文献   

11.
The paper analyzes the demand and supply characteristics of the Indian telecommunications market, with the aim of contributing to the debate on the effectiveness of universal access policies in developing countries. The discussion is supported by some empirical evidence derived from a small time-series-cross-section dataset, containing mainly information on the fixed-lines segment of the market. The analysis suggests that the price elasticity of demand for fixed lines might be sensibly higher than the levels usually found in developed countries, while the crucial role of income and other sociodemographic variables seems to be confirmed. The paper also studies the impact of cellular penetration on fixed-lines diffusion. The results suggest the existence of a (positive) network effect in low penetration areas, while substitution (displacement) seems to arise in the most developed ones. Finally, the paper analyzes the supply side of the market, to assess the impact of market competition on investment. Competition seemingly helps stimulating investment in the most developed areas, but does not seem to have a significant impact in the less developed ones.  相似文献   

12.
阐述了发电设备全寿命周期费用(Life Cycle Cost,LCC)的基本理论及计算方法,针对发电设备LCC的影响因素之间存在的客观联系,假定因素之间相互独立,对其中某2个因素的变动幅度进行了一定的修正,使之更贴近实际。以某2×600MW火电机组为例,选取若干影响因素,求得其全寿命周期费用净现值。对目标净现值进行单因素和多因素敏感性分析,以寻找目标值与影响因素之间所存在的内在联系,为设备投资以及后期优化管理提供决策依据。  相似文献   

13.
In 1996, the Korean mobile communication market was the first in the world to commercialize the code division multiple access (CDMA). Since then, the voice-based mobile phone market has continued to grow and has now reached near saturation. Having recognized the potential of the mobile data service as a new source of profit, telecommunication operators are scrambling to evolve 3.5 generation (3.5G) technology in order to lead market competition. Recently, the Korean 3.5G mobile telecom market has faced stiff competition from CDMA-based EVDO Rev.A and global system for mobile telecommunications (GSM)-based high-speed downlink packet access (HSDPA). In addition, the world's first wireless LAN-based wireless broadband internet (WiBro) service was commercialized in June, 2006. This paper reviews the current status of the 3.5G technology and analyzes the service standardization strategies from the viewpoint of technological evolutions. This paper also suggests implications for Korea's specific circumstances where different mobile telecom technologies complement and compete with one another. Korea's experiences may serve as important lessons for other countries or operators who try to introduce the 3G and look beyond mobile telecom technologies.  相似文献   

14.
江苏省秸秆电厂投资运营状况分析   总被引:11,自引:3,他引:8  
介绍了江苏省秸秆发电的现状,并根据江苏省主要农作物秸秆产量认为秸秆发电在江苏省还有发展空间。分析了秸秆电厂的工程造价和发电成本构成,论述了秸秆电厂运营的特点和提高秸秆电厂项目投资效益的途径,提出了需要国家政策扶持的建议。  相似文献   

15.
To continue balancing supply and demand for power is a growing challenge on Germany’s path to producing 80?% of its electricity from renewable sources by 2050. Large-scale investment into a range of technologies will be required to provide the flexibility necessary for balancing. This paper introduces a simple analytical framework to evaluate the German legislator’s numerous efforts to address this challenge. It then proceeds to make two proposals as to how flexibility can be sourced more cheaply. Priority should be given to measures that enable the existing power markets to generate stronger rewards for flexibility. We thus call for financial incentives for variable electricity tariffs to elicit more consumer response and for investment subsidies instead of feed-in tariffs for more demand-oriented renewable power generation. If additional explicit incentives for flexibility are necessary, they can be provided through a market for flexibility.  相似文献   

16.
Investment decisions in the wireless industry applying real options   总被引:1,自引:0,他引:1  
The wireless industry is one of the most capital intensive high-technology industries. This paper applies real options techniques to estimate investments under uncertainty in two new ventures: (a) deferral of the expansion from 2.5G to 3G networks; and (b) expansion of a 2.5G network using Wi-Fi as an alternative technology. The cases are examined and analyzed both qualitatively and quantitatively, using realistic assumptions and parameters. Investment cost, number of subscribers, pricing of services, and risk are at the core of investment decision processing. In both cases, sensitivity analysis of the value of the (real) option considering the above key parameters was conducted, to extrapolate useful findings that should be taken into consideration by the decision makers in wireless companies.  相似文献   

17.
Fifth generation (5G) networks raise governance and management challenges that did not exist in 3G and 4G wireless technologies. Advanced wireless functionality enables new applications and services based on smart, physical, network infrastructures, many of them expected to be localized. As a general-purpose technology, 5G can be configured in numerous ways to support innovative applications across many sectors. Smart network applications and services must integrate physical and virtual components in innovative ways. In addition, general capabilities of 5G must be combined with complementary technologies, such as big data analytics and edge cloud services, to create services for specific use cases. Varying throughput and latency requirements of distinct use cases require differentiated technical solutions. Appropriate frequencies must be aligned efficiently with other features within the footprint of particular, local industrial networks. National policy makers, suppliers, and users are responding differently to these governance and management challenges. These approaches balance differently the trade-offs between experimentation, differentiation, and harmonization. Comparative analysis can inform gradual improvements of the governance of 5G-based, local industrial networks.  相似文献   

18.
电力市场环境下发电环节的节能减排   总被引:2,自引:5,他引:2  
李梅  文福拴 《电力技术经济》2007,19(4):27-31,60
介绍了国内外在发电环节采用的两种节能减排技术,即洁净煤技术和可再生能源发电技术。从政策支持、价格鼓励、税费减免、科研和产业化的促进等多个方面论述了电力市场化改革环境下,发电环节节能减排的政策、法规及发展思路。建议对化石燃料发电征收较高的能源税、CO2税、SO2税以及征收CO2排放费用,增大可再生能源发电配额比例,鼓励私人投资,建立绿色电力发展基金,加快技术和设备的国产化进程等。  相似文献   

19.
System considerations support a discussion of selected factors influencing the economic viability of power plants with CO2 sequestration technology (CCS, for carbon dioxide capture and storage), leading to conclusions when and how much of their potential may conceivably be realised. The CCS realisation is interconnected to investments into other technologies, to technological advances, to the price of CO2 emission certificates, to plant dispatch, and to the prices of power. In a system of CCS potential realisation by individual actors, these variables are endogenous. This article is mainly about them. CCS is more of a long term option than a bridge technology. In contrast to other CO2 reduction technologies, both economic operation and economic investment necessarily require high CO2 certificate prices. An increase in power plant efficiency without CCS, switching to natural gas and power generation from renewable sources involve more mature technologies that may benefit from further application within the coming decades. Even far beyond 2020 this effect may delay and dampen the potential of CCS technology. An economic or market potential is dependent to a lesser extent on assumptions about future barriers but rather on their dynamic interactions.  相似文献   

20.
《Telecommunications Policy》2002,26(9-10):505-535
As mobile wireless unfolds, the business-world looks for an assessment of the technical and competitive landscape, for a high return on investment opportunities, for sweet spots in the value chain, and for value propositions of the industry. This requires an understanding of the evolving value chain and market structure of the mobile wireless industry. To help the business-world deliver on the full promise of mobile wireless, this paper describes the elements of the evolving value chain and its major players. The paper also describes how emerging technological solutions are unleashing the potential of the value chain.  相似文献   

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