Design of Advanced Linear Circuits and Systems

先进线性电路和系统的设计

• 批准号: RGPIN-2014-05653
• 负责人: Maundy, Brent
• 金额: $ 1.82万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=611762
• 关键词: Design; Advanced; Linear; Circuits; Systems

My research is aimed at designing and developing new circuits capable of performing some of the simplest mathematical functions using analog circuits. Several of these functions include amplification, filtering, multiplication, division, sensing, and the general processing of signals. There is a need to constantly reexamine such functions because technology is rapidly changing and what may work well in one integrated circuit technology may have to be revised in another. One example of such a function is a logarithmic or exponential digital to analog converter (DAC) function that I am seeking new ways to implement in new integrated circuit technologies. This is to meet the challenges associated with shrinking power supplies and transistor sizes. My research into new logarithmic and exponential multiplying D/A amplifiers is focused on using first and possibly second order approximations to logarithmic and exponential functions, and expanding the dynamic range of those functions to meet realistic requirements. The expectation is that hardware savings may be gained without excessive losses through the use of these approximation functions. Logarithmic DACs find application in automatic gain control circuits and gain or volume controls. Another example of general processing of signals is in filter design. All electronic circuits use filters that pass low or high frequencies, a band of frequencies, or eliminate a particular band of frequencies. Much of my proposed and yet untapped research is aimed at allowing more choice of several recently newly introduced parameters associated with the frequency response of these new filters, hence allowing more precise filter design, than conventional methods. To accomplish much of this, research into new filter circuit design is focused on an emerging and exciting use of fractional capacitors in filter structures. This unique and relatively unexplored element has the property that its impedance is no longer pure imaginary, but it has a real component to its impedance. This element whose properties are not found naturally in most materials has been used by our group to date to produce unusual characteristics in filters such as asymmetry and sharp filter responses that are not available through commercial capacitors or conventional means. As part of our ongoing research I have also discovered they can be used in modeling the electrical behavior of human tissue, agriculture and looking for cancers. While fractional capacitors are presently not available commercially, this entire research has the potential to revolutionize many other disciplines of electrical engineering, all the while being cross discipline. Why, because fractional calculus long time use in controls and system identification has not been really applied to addressing electrical engineering problems and seeking new ways of doing things. My research work therefore seeks to add to the general body of knowledge both in the area of analog fractional filtering and modeling element properties. The latter application, to possibly aid in bioimpedance measurements in general, or characterizing tissue or monitoring for physiological changes. Any discoveries made here can be further used as a potential diagnostic tool for cancer detection and monitoring physiological changes due to other health conditions. With this application, the need for low-cost, wearable/implantable monitoring devices using indirect measurement techniques becomes extremely useful in both monitoring and possibly keeping health costs down.

我的研究旨在设计和开发能够使用模拟电路执行一些最简单的数学函数的新电路。这些功能包括放大、滤波、乘法、除法、传感和信号的一般处理。需要不断地重新检查这样的功能，因为技术正在迅速变化，并且在一种集成电路技术中可能工作良好的功能在另一种集成电路技术中可能不得不被修改。 这种函数的一个示例是对数或指数数模转换器（DAC）函数，我正在寻求在新的集成电路技术中实现的新方法。这是为了应对与缩小电源和晶体管尺寸相关的挑战。我对新的对数和指数乘法D/A放大器的研究集中在使用对数和指数函数的一阶和可能的二阶近似，并扩展这些函数的动态范围以满足实际要求。期望的是，通过使用这些近似函数，可以在没有过多损失的情况下获得硬件节省。对数DAC可用于自动增益控制电路和增益或音量控制。 一般信号处理的另一个例子是滤波器设计。所有的电子电路都使用滤波器来通过低频或高频，一个频带，或消除一个特定的频带。我提出的许多尚未开发的研究旨在允许更多的选择最近新引入的几个参数与这些新的滤波器的频率响应，从而允许更精确的滤波器设计，比传统的方法。 为了实现这一目标，对新滤波器电路设计的研究集中在滤波器结构中分数电容器的新兴和令人兴奋的使用上。这种独特的和相对未开发的元素具有的属性，它的阻抗不再是纯虚的，但它有一个真实的组成部分，其阻抗。该元素的特性在大多数材料中都不存在，迄今为止，我们的研究小组一直在使用该元素来产生滤波器中的不寻常特性，例如不对称性和尖锐的滤波器响应，这些特性是通过商业电容器或传统方法无法获得的。 作为我们正在进行的研究的一部分，我还发现它们可以用于模拟人体组织的电学行为，农业和寻找癌症。虽然分数电容器目前还没有商业化，但整个研究有可能彻底改变电气工程的许多其他学科，同时也是交叉学科。为什么，因为分数阶微积分长期用于控制和系统识别，并没有真正应用于解决电气工程问题和寻求新的做事方法。因此，我的研究工作旨在增加到一般的知识体系，无论是在该地区的模拟分数滤波和建模元素的属性。后一种应用可能有助于一般的生物阻抗测量，或表征组织或监测生理变化。这里的任何发现都可以进一步用作癌症检测和监测其他健康状况引起的生理变化的潜在诊断工具。在这种应用中，对使用间接测量技术的低成本、可穿戴/可植入监测设备的需求在监测和可能降低健康成本方面变得非常有用。