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排序方式: 共有199条查询结果,搜索用时 46 毫秒
1.
A fundamental policy in European broadband regulation is unbundled access to the local loop of the incumbent telephone company. We present comparative static results that show as the access price decreases, the retail price decreases, the variety of plans offered by Internet service providers increases and the quantity of each variety increases when a threshold condition is met. Using data from 18 European countries from 2006 to 2012, we find empirical support for these results when Internet product variety is measured by variation in download speeds.  相似文献   
2.
The advanced development of broadband access is an inevitable step toward supportive daily lives and sustainable economic growth. However, the decisive outcome of the development relies heavily on the demand side. Consumer choice among advanced Internet broadband technologies will determine the achievement of the development. This study aims to illustrate that consumer decisions on choices of advanced Internet access are influenced by the emergence of the Internet of Things (IoT) applications. A bivariate probit model is applied to examine the effects of IoT, consumer's individual characteristics, and their current use of networks on their decision pertaining to the choice of advanced Internet access. Using Thailand as a case study, the result indicates that the emergence of IoT applications accelerates the adoption of both advanced mobile broadband (5G) and advanced fixed broadband (FTTH). This finding may help policy makers to optimize the future direction of the Internet infrastructure development in Thailand, and also countries in a similar stage.  相似文献   
3.
This paper investigates the high-speed broadband situation in the EU and its prospects. It uses a deployment model to estimate the investment required to meet the Digital Agenda for Europe (DAE) broadband targets set by the European Commission in its Europe 2020 strategy at different stages: as of 2016, after expected operators’ deployment, after public subsidies and leveraged investment, and as expected in 2020. The model uses data at the NUTS3 level, which is the most granular level that has data available on the status of broadband deployment, to arrive at a coherent and comparable framework. From the different perspectives on the investment to meet DAE targets, the paper concludes on the need for an appropriate combination of incumbent and alternative operators investments, public subsidies and leveraged investments, and new investments, both public and private and non-existing as of 2016, examining their feasibility and the impact of different regulatory, technical, and policy strategies.  相似文献   
4.
The literature on broadband policies has been focusing on the possible role of mobile broadband as a means for addressing geographical digital divide in areas with no or inadequate fixed broadband infrastructure coverage. Broadband plans designed by most of the industrialized countries take the substitutability between fixed and mobile technologies for granted, with restrictions essentially relating only to bandwidth performance. We explore the determinants of individuals' private access (away from work) to the Internet with the smartphone through a mobile broadband connection, focusing on the role played by Internet uses and taking into account the availability of a fixed broadband connection at home. The results of our econometric exercise, carried out on microdata referred to Italian individuals, provide original and interesting evidence: a complementarity effect between mobile and fixed broadband is found for browsing, video streaming, gaming and cloud services; a substitution effect emerges for social networking and music streaming. Such increasing complexity of individuals’ broadband usage patterns should be acknowledged in the way broadband coverage is mapped and policies designed, adopting a more ecosystem-oriented approach which integrates supply- and demand-side features. A first step in this direction is the inclusion of some, so far neglected, key-attributes of the demand (data traffic allowance, latency, ease of interconnection with Internet capable devices) among the relevant dimensions of policy design.  相似文献   
5.
介绍了信道化接收机实现的方案和工作原理,并对其接收系统中重要部件——宽频带放大器做了重点介绍,针对低噪声和宽频带2个主要指标,采用平衡式放大器进行设计,最后给出了仿真结果。  相似文献   
6.
推导并分析了存在增益和相位跟踪等误差情况下,功率放大器前馈技术对三阶线性失真的改善情况,并从原理上论述了前馈技术的工作原理.前馈技术一般可将三阶互调降低10~30 dB,在新一代的抗干扰跳/扩频电台中有广泛应用.  相似文献   
7.
针对数字锁定放大器中稀疏分解算法检测精度受限的缺点,结合非线性方法进行补偿,采用混沌检测联合稀疏分解的算法设计了数字锁定放大器。数字锁定放大器借助稀疏分解算法估计信号参数,根据估计得到的参数设计对应混沌系统;利用混沌系统检测信号的过程中产生间歇性混沌状态,并通过测量间歇性混沌状态的周期,精确检测信号。最终,在信号的信噪比低至-20 dB时可以成功检测信号,频率精度达到0.05 Hz,提供了一种非线性微弱信号检测方法。  相似文献   
8.
豆帅涛 《价值工程》2015,(18):198-200
为了详细分析目前比较常用的555定时器和运放构成的矩形波发生器,填补其他文章仅单单分析一种电路的空白,利用Multisim强大的仿真分析功能,结合理论计算,对这两种方波发生器进行输出电压特性、占空比调节、输出频率、电源电压范围等方面的比较分析,希望给制作矩形波发生器的读者提供一定的参考价值。  相似文献   
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10.
Broadband is seen as a vector of economic growth and social development. In the developing world, mobile technologies are widely adopted and mobile broadband is progressively rolled-out with high expectations on its impact on the countries’ development. We highlight what the determinants of mobile broadband use are in four Sub-Saharan countries. Using micro-level data coming from household surveys over 5 years, from 2013 to 2017, we show that SIM card ownership and being part of an online social community has a strong positive impact on mobile broadband use. We also highlight a positive correlation between digital inclusion and financial inclusion as mobile money users and bank account users are found to be more inclined to use mobile broadband. However, beyond apparent similarities, mobile broadband is used in different ways according to countries specificities. For instance, among the non-mobile owners in Nigeria, the unemployed are the most likely to use mobile broadband, most probably for job search practices, while it is rather used by students for information gathering in other countries. Finally we show that those excluded from mobile broadband use are the eldest, those with the lowest level of education, and women.  相似文献   
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