功率VUMOSFET器件阈值电压最佳化设计

从功率VUMOSFET器件结构出发,通过使用模拟软件SILVACO进行工艺和器件仿真,根据仿真结果分析了器件沟道掺杂浓度分布对阈值电压的影响,进而提出工艺改进的措施.对功率VUMOSFET的设计与生产具有指导意义.     

Group-blind multi-user detection under multi-path channel

This article proposes an improved generalized side-lobe canceller(GSC)receiver structure based on a new group constraint,which is suitable to eliminate multiple-access interference(MAI),inter-symbol interference(ISI)in direct-sequence code-division multiple access(DS/CDMA)downlink multi-user system.The new group constraint is deduced to construct the group-blind adaptive multi-user detector.The analysis indicates that the improved GSC under the new constraint not only retains the property of suppressing ISI and canceling MAI,but also can extract useful information from the succeeding bit for the desired user.The simulations show that the improved GSC filter can cancel the MAI efficiently whether the wireless channel length is short or long,and achieve better performance than other compared filters.     

电子书阅读器：过渡时期和小众市场的商机

与司机曾因汽车太贵而受重视一样,电子书阅读器因E-ink屏稀缺而流行,并在过渡阶段有一定市场。一旦包括屏在内的产业链成熟,“电子书”功能将融入很多产品而无处不在,纯电子书阅读器仅限于高端和小众市场。     

Cooperative Communication Based on Spectrum Aggregation in LTE Further Evolution

The implementation of wide band radio transmission may occur in two parallel ways:designing a new system with larger bandwidth,or constructing a cooperative system based on existing systems.The former is a spectrum aggregation scheme based on multi-carrier transmission within one system,while the latter fulfills spectrum aggregation based on multi-carrier transmission among systems.On the one hand,the advantage of the multi-carrier transmission scheme within a system and among systems is that the existing R...     

GaAs基长波长量子点激光器增益和阈值电流密度的理论分析

基于谐振子模型的量子点能级,计算了包括和排除激子影响时多能级的增益谱.考虑了低温时非平衡载流子分布.得出了较宽温度范围内阈值电流密度的变化,包括负温度及振荡温度效应.研究了垂直层叠和p型掺杂对量子点激光器性能的改善,并讨论了获得极小阈值电流密度时的最佳量子点密度.     

思科：ISR重新定义路由法则

近期，思科系统(中国)网络技术有限公司在北京金帆音乐厅举办了“超越路由交响音乐会暨新品介绍会”。在会上，思科以别开生面的交响音乐会方式，演绎出接入端路由发展历史与音乐发展脉络的相似之处。接人端路由的四个发展阶殷分别通过四个乐章来表现，向与会勾勒出其技术演变的历程。     

Distributed Optical Fiber Sensor for Multi-point Temperature Measurement

The distributed optical fiber sensing technology is overviewed, which is based on Raman scattering light theory. Basic operation principle, structure, system characteristics and signal processing are discussed. This structure and method of the signal processing possess of certain spatial resolution, hence will ensure the practicability of system.     

5．8GHz无线宽带接入系统应用设计

无线宽带接入网技术是近几年才发展起来的一种新技术。其码元速率为10、20、54、108 Mbit／s，有效传输速率分别为7、14、20Mbit／s和50Mbit／s，通信距离从几公里到几十公里，多点协议设备能很好地解决方圆几十公里的覆盖。随着国家对5．8GHz     

什么是OFDM

正交频分复用（OFDM,Orthogonal Frequency Division Multiplexing）是一种多载波数字调制技术,也可以被当作一种复用技术。具有频谱利用率高、抗多径干扰等特点,OFDM系统能够有效地抵抗无线信道带来的影响,例如信道的频率选择性衰落,脉冲噪声和共信道干扰的影响。     

Mitsubishi LaserVue激光电视即将登场

自从今年1月份三菱宣布即将推出激光电视后,我们就一直在关注这个产品。从最近得到的消息来看,这款令人激动的产品即将上市！新款上市的产品包括65英寸和73英寸两种型号,电视刷新频率为120Hz,亮度为500cd/m2.作为首款由激光驱动的电视Laser Vue有望在家庭娱乐的领域中为大家带来以前没有体验过的颜色表现,三菱称其为“真正的多维体验”。