实现了一款超宽带低噪声放大器( UWB LNA)。该UWB LNA由输入级、中间级和输出级组成。在输入级,采用两个共栅配置构成了噪声抵消技术,减少了噪声,在此结构基础上进一步采用了跨导增强技术,提高了增益。同时插入的电感Lin提高了LNA在宽带范围内的增益平坦度。中间级放大器,在漏极并联电感产生零点,提高了LNA的带宽。输出级为源极跟随器,较好实现了LNA的阻抗匹配。基于0.18μm TSMC CMOS工艺仿真验证表明,在4 GHz~10 GHz频带范围内,电压增益( S21)为(19.2±0.3)dB,噪声系数(NF)介于2.1 dB~2.4 dB之间,输入、输出反射系数(S11、S22)均小于-10 dB。在9 GHz时,输入三阶交调点(IIP3)达到-7 dBm。在1.8 V的电源电压下,功耗为28.6 mW。

An ultra-wideband low noise amplifier ( UWB LNA) was presented. The UWB LNA is composed of input stage,intermediate stage and output stage. At input stage,noise cancellation structure constructed by two common-gate configuration is utilized to decrease noise figure,Gm-boost structure is used to enhance gain,the inserted inductor Lin improves the gain flatness of the LNA within the wideband. At intermediate stage,the bandwidth is broaden due to the zero generated by shunt inductor at the drain of amplifier. The output stage is a source follower which provides a good output matching easily. Based on 0.18μm standard CMOS process,the LNA is verified. The voltage gain( S21 ) main-tains 19.2 dB± 0.3 dB,noise figure(NF)swings from 2.1 dB to 2.4 dB,input reflection(S11)and output reflection (S22)are less than -10 dB within the range of 4 GHz~10 GHz. The input intercept point(IIP3)is-7 dBm at 9 GHz. The LNA consumes only 28.6 mW from a 1.8 V voltage.

宽带移动通信信道处于微多径条件下由于带宽受限和多径传播导致的码间干扰使信号发生畸变，需要进行BPSK调制，增强冲激响应。在移动通信系统微多径条件下，提出一种宽带移动通信BPSK调频信号冲激响应增强算法，设计极大似然判决反馈均衡的宽带移动通信信号前馈调制算法，设计多径条件下宽带移动通信信道模型与最优接收机，得到多径条件下时延扩展与信道特性测量模型，在输入端周期性地发送超过信道脉冲响应长度的数据训练序列，基于极大似然准则进行BPSK调频信号调制，跟踪信道变化的能力，实现微多径条件下宽带移动通信的前馈调制。结果表明，算法能使波达方向角的相关峰值增强，调制特性更为稳健，输出信道冲激响应有较好的增益，增强带宽，提高了通信质量，展示了算法在移动通信信道改善方面的应用价值。

The broadband mobile communication channel in multipath conditions has limited bandwidth and multipath propagation, it causes inter symbol interference distortion of the signal. The maximum likelihood decision feedback broad?band mobile communication signal modulation algorithm is proposed based on the feed forward balanced multipath condi?tions, the broadband mobile communication channel model and the optimal receiver is obtained, get the measurement mod?el of multipath delay spread and under the condition of channel characteristics, at the input end periodically over the length of the training sequence data the channel impulse response is enhanced, BPSK FM signal modulation is obtained based on the maximum likelihood criterion, ability of tracking channel is improved, feed-forward modulation broadband mobile com?munication micro multipath conditions is realized. Results show that the algorithm can make the correlation peak in the di?rection of arrival angle enhance, modulat

随着学校转型发展和五大教学改革的深入，师生对获取信息资源的校园宽带依赖度和要求越来越高。校园宽带对办学质量和教育改革发展有着重要影响。此次调查在分析重庆文理学院校园宽带满意度影响因素的同时，建立了评价体系。在此基础上，进行满意度调查分析，提出增强满意度的建议，便于运营商完善对校园宽带的管理，实现校内外信息的快速、有效传递，使教学、科研、管理等工作走入信息化、网络化，从而提高办学水平。

With the development of school transformation and the deepening of five teaching reform, the dependence and the de-mand of teachers and students to get information resources of campus network are higher and higher. Campus network for educa-tion quality and education reform and development has an important influence. The survey made an analysis of the influence fac-tors of the Chongqing University of Arts and Sciences campus broadband satisfaction, and established the evaluation system. Based on that, satisfaction investigation was analyzed, the advice to enhance the satisfaction was proposed, which is convenient for operators to improve the management of campus network, to realize the fast, effective transfer of internal and external information, to make the teaching, scientific research, management and other work into the informatization and networking, so as to improve the level of running a school.

应对三网融合,增强市场竞争力,更好地支撑和拓展广电宽带业务的发展,从互联网的应用发展变化入手,研究部署新一代互联网内容聚合平台,通过海量内容聚合应用,实现互联网全业务代理;同时通过智能引导、用户空间等应用进一步锁定用户流量,并为三屏互动提供技术支持。系统投入使用显著提升了宽带服务质量,降低了运营成本,适应和支撑了三网融合的发展需求。

To cope with the trend of the development of the three nets fusion , enhance market competitiveness , better support and expand Broadcasting broadband business development , this system , from the application development of the Internet , deploys a new generation of Internet content aggregation platform , through mas-sive amounts of content aggregation application , realizes all Internet business agent;at the same time , through intelligent guide , user space application , system further lock user traffic , and provide technical support for three screen interaction .Since system put into use , broadband significantly increase the service quality , re-duce operating costs , to meet the needs of and support the development of the three nets fusion .

对于新一代的无线网络,宽带无线系统的融合将成为一个重要的技术难题。近年来,尽管一些研究人员已经提出了几种技术方案用来增强第二代媒体访问控制协议(MAC),但这些设计主要针对的是数字信息。针对实时宽带信源给出一个了更好的集中控制访问技术,这项技术通过实现信息源的统计复用,并根据不同用户的服务质量需求来对无线终端进行组合,使之形成一个固定的有线宽带网络。同时这项技术将轮询方式与随机接入方式整合在一起,基站中的数据包调度程序负责动态地选择最高传输需求吞吐量的接入方式。对上述方法进行了性能测定,并估算了相关的参数。

For the new generation of wireless networks,the convergence of wireless systems with broadband services is becoming an important technical issue.In recent years,several schemes for enhancing second-generation media access control(MAC)protocols have been proposed,which,however,mainly focus on digital information.In this paper,an enhanced centrally controlled access technique for real-time broadband sources is presented.It enables full integration of wireless terminals into fixed wired broadband networks by realizing the statistical multiplexing of sources and depending on the user''s requirements of quality-of-service. Furthermore,the technique combines random access with polling,and the packet scheduler running at the base station dynamically selects the access method with the highest throughput for transmission of capacity requests. The performance of the method is tested,and the relevant parameters are calculated.