基于可重构FPGA技术的自适应FIR滤波器的实现

有限冲激响应(FIR)滤波器设计遇到的难题是滤波要进行大量乘法运算,即使是在全定制的专用集成电路中也会导致过大的面积与功耗.对于用硬件实现系数是常量的专用滤波器,可以通过分解系数变为应用加、减和移位而实现乘法.FIR滤波器的复杂性主要由用于系数乘法的加法器/减法器的数量决定.而对于自适应FIR滤波器,大多数场合下可用数字信号处理器(DSP)或CPU通过软件编程的方法来实现,但是对于要求高速运算的场合,VLSI实现是很好的选择.基于这一考虑,可以用符号数的正则表示(CSD)码表示系数, 再利用可重构现场可编程门阵列(FPGA)技术实现.可重构结构的应用,能保证系统的其余部分同时处于运行状态时实现FIR滤波器系数的更新.文中利用CSD码和可重构思想,提出了用FPGA实现自适应FIR滤波器的一种方案.     

双积分A/D转换器的量程自动转换

介绍了一种双积分式A/D转换器在宽范围量程测量中的自动量程转换技术.在测量仪表的输入通道中,用计数器对双积分型A/D转换器本身所固有的过量程/欠量程信号计数,计数器的输出作为量程编码去控制量程的选择,同时又是送到CPU的量程指示信号.该技术扩大了A/D转换量程,提高了精度,设计简单,工作可靠.     

朗讯cdma 1x基站分组管宽度的配置

简单介绍朗讯系统cdma 1x基站分组管(PP)宽度的配置，并对朗讯cdma 1x基站分组管宽度不合理的配置及信道板扩容后的PP宽度配置进行了案例分析。     

Density Measurement of Liquid Ni-Ta Alloys by a Modified Sessile Drop Method

The density of liquid Ni- Ta alloys was measured by using a modified sessile drop method. It is found that the density of the liquid Ni- Ta alloys decreases with the increasing temperature, but increases with the increase of tantalum concentration in the alloys. The molar volume of liquid Ni- Ta binary alloys increases with the increase of temperature ancl tantalum concentration.     

Active set truncated-Newton algorithm for simultaneous optimization of distillation column

An active set truncated-Newton algorithm (ASTNA) is proposed to solve the large-scale bound constrained sub-problems. The global convergence of the algorithm is obtained and two groups of numerical experiments are made for the various large-scale problems of varying size. The comparison results between ASTNA and the subspace limited memory quasi-Newton algorithm and between the modified augmented Lagrange multiplier methods combined with ASTNA and the modified barrier function method show the stability and effectiveness of ASTNA for simultaneous optimization of distillation column.     

Effect of oxygen vacancies on transformation of zirconia at low temperatures

The effect of oxygen vacancy on the stability of phase structures and phase transformation of zirconia at low temperatures was studied using an electrochemical technique. It is suggested that the decrease of oxygen vacancies decreases the stability of metastable tetragonal zirconia and promotes its transformation to the monoclinic phase. This revised version was published online in November 2006 with corrections to the Cover Date.     

实时多任务操作系统响应性能预估和测试

本文给出了作者开发的一个单处理机实时多任务操作系统的响应性能（响应时间，同步时间）的实验结果和／或估算。与国外同期文献发表的数据相比，指标先进。     

无线电引信被干扰率及抗干扰率

本文从无线电引信相对杀伤比率出发，引伸出引信被干扰率及抗干扰率的定义及计算公式。