激赏世界杯的良伴--飞利浦(Philips)DVDR3375刻录机

想把旅途见闻与人分享?想把家庭节日欢聚保留珍藏?想将小孩子的整个成长过程,从呱呱坠地、蹒跚学步到生日聚会、毕业典礼完全记录?想把整届世界杯录下来慢慢欣赏?一切的美好、所有的感动将会因记录而格外珍贵,但以往的老式录像机早已淡出人们的视野,而能记录珍爱的视频和定时录制电视节目的功能在今天仍然有很大的需求,特别是随着人们工作节奏的加快,大部分人都没有时间观看自己喜爱的电视节目。针对这种需求,飞利浦电子推出了全新的DVD录像机产品——DVDR3375。     

Picosecond pulse response of a travelling-wave semiconductor laser amplifier

The dynamic pulse response of a travelling-wave semiconductor laser amplifier has been investigated. Peak output powers greater than 100 mW, with a fibre-to-fibre gain of 10 dB, have been observed for narrow pulses (<50ps FWHM) at low repetition rates. The dynamic bandwidth of the amplifier has been shown to be at least 50 GHz.     

Two-way transmission at 2.488 Gbit/s over a 132 km operational submerged cable using erbium-doped fibre power amplifiers

The results of a field trial on the UK-Channel Islands No.7 cable, in which ruggedised, broadband erbium power amplifiers were used to achieve two-way transmission at 2.488 Gbit/s over a 132 km submerged cable is reported.<>     

Developing the Access Network

An overview is presented of current and forthcoming access network technologies and how they are likely to be deployed in access networks around the globe. These technologies are discussed in the light of commercial considerations, such as the current market structure, the impact of competition and regulation, as well as the demand for new broadband and Internet services. Various technology options are introduced and discussed, and issues presented that would influence the choice of such technologies for different operating companies.     

Transmission of 10 Gbit/s directly modulated DFB signals over 200km standard fibre using mid-span spectral inversion

Dispersion compensation by mid-span spectral inversion has been used to achieve the transmission of 10 Gbit/s signals from a directly modulated DFB over 200 km dispersive fibre. The spectral inversion is provided by nondegenerate four-wave mixing in a semiconductor optical amplifier     

Field demonstration of coherent transmission system with diode-pumped erbium doped fibre amplifiers

Reports a field demonstration of 622 Mbit/s DPSK and FSK coherent transmission over 200 km of installed single mode fibre. Diode-pumped erbium doped fibre amplifiers were used as both power amplifiers and repeaters. System loss budgets of more than 68 dB were achieved with an intermediate amplifier repeater gain of 16.5 dB. Both systems incorporated fully automated endless polarisation control.<>     

New Gaussian-based approximation for modelling non-linear effectsin optical fibers

The use of Gaussian field approximations enables simple analytical models to be derived for non-linear fibers and doped-fiber lasers and amplifiers. A new Gaussian-based method is described that is as easy to use as the standard Gaussian approximations, yet provides an rms error in the confinement factor of only 1.1% for a wide range of matched-cladding fibers. Similar accuracy is obtained for depressed-cladding fibers. The new approximation is used to predict Raman gain in a typical experimental MCVD fiber and excellent agreement is obtained between theory and experimental measurements     

Raman-assisted long-distance optical time domain reflectometry

The measurement range of long-haul optical time domain reflectometry (OTDR) may be extended substantially by introducing distributed Raman gain in the fibre under test. With semiconductor pump lasers an increase in the fault location range of at least 10 dB one-way is achievable, without requiring the OTDR to have an increased processing dynamic range.<>     

经典与时尚的有机融合--KEF KHT6000家庭影院音箱系统

1961年成立于英国的 KEF 是音响界一个具有传奇色彩的经典品牌。KEF 一直致力于研发声音更加完美的音箱,在单元结构、设计与材料方面进行了创新,发明了具有专利的“同轴共点”(Uni-Q)技术,并进行铷钴强磁体的研发。众多的创新技术与过硬的产品品质给 KEF 带来了勃勃生机,也给其带来了众多的荣誉与广泛的认同。KEF 在两声道音箱市场享有极高的知名度与市场地位,近年来更是积极开拓5.1声道家庭影院扬     

The Global Access Challenge

This paper looks at the access options and challenges facing the new operators in an increasingly liberalised telecommunications market. It considers the opportunities and risks associated with moving from a predominantly leased-line approach to one where a combination of owned and indirect access is also used. The business structures that can be used to create a new operator are considered, together with a high level view of the technology options they have. The fundamentals of implementing a network are also discussed.