研究生论文摘要文献综述写作

1、u高速模高速模/ /数转换器常规参数的动态测试数转换器常规参数的动态测试高速模似/数字转换器（adc）被广泛应用于视频和无线通讯等领域。如何对高速adc的性能进行准确评估是一个受到高度关注的课题。准确评估高速adc的性能需要采用动态测试方法。文章运用码密度直方图分析法，分析了高速adc常规参数，包括失调、微分非线性、积分非线性、失码、增益误差等的动态测试。背景太多，专家都知道，不宜进入摘要。udynamic test of general parameters for high-speedanalog-to-digital convertershigh-speed analog-to-digi

2、tal converters (adc) are widely used in video and wireless communications. much attention has been paid to evaluation of the performance of high-speed adcs. in this paper, a dynamic test method based on code density histogram analysis is employed to analyze general parameters of the high-speed adcs,

3、 such as offset, differential nonlinearity, integral nonlinearity, missing code, and gain errors.ucdmacdma移动通信系统中的多址干扰及抑制移动通信系统中的多址干扰及抑制技术技术相对fdma 及tdma，cdma具有一系列的优点，这些优点使得cdma技术在日新月异的移动通领域中所处的地位越来越重要，已经成为新一代移动通信以及未来个人通信中最具竞争力、最具发展前景的无线多址技术。但在cdma已经成为第三代移动通信主流技术的时候，要真正达到预定的目标，还有许多关键技术要解决，其中最为关键的就是要突

4、破克服cdma系统中多址干扰（mai）的技术。u光子晶体光纤参量放大的理论模拟光子晶体光纤参量放大的理论模拟光子晶体光纤具有高非线性系数和非常灵活的色散特性，通过调节光子晶体光纤的结构参量，可在具有高非线性系数的同时对光子晶体光纤的零色散波长（0）进行调节。利用光子晶体光纤的这些特性可实现在所需波长上的高效率的参量放大。本文采用厄密-高斯函数展开的方法，计算了六角形光子晶体光纤（hf）的零色散波长，发现当气孔间距在1.1 m 和2.6 m 之间时，光子晶体光纤的零色散波长在1.55 m 附近，并给出了零色散波长时气孔间距和气孔大小的关系曲线。对光子晶体光纤中的参量放大（opa）进行了理论模拟，

5、计算表明在20 m光子晶体光纤中，当峰值功率为10 w时，参量放大的增益可达60 db，或可获得300 nm增益带宽。usimulation of optical parametric amplification using holey fiberholey fiber (hf) can have high nonlinearity and very flexible dispersion. the zero-dispersion wavelength (0) of hf with high nonlinearity can be adjusted by changing the struct

6、ure parameters of pcf. this can be used to generate high efficient optical parametric amplification (opa) at desired wavelength in hf. hermite-gaussian functions have been used to calculate the zero-dispersion wavelength of hexagon hf, calculations show that when pitch is between 1.1 m and 2.6 m, the0 of hf is around 1.55m, and the relation of pitch vs air hole diameter at 0 has been given. simulations of the opa in hf show that gain of opa can reach 60 db in o