CAREER: Advanced interface circuits for communication systems through architecture, circuit, and software innovation

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

Efforts to create low cost,high performance communication systems in the future will be chal- lenged by the high cost of developing new interface circuits that are suited to their needs.These interface circuits serve as the intermediary between real world signals,which are analog in nature, and the digital processing engines at the core of the system.Current interface circuits are primarily analog in their implementation,which makes their performance highly sensitive to manufacturing variations in the process they are fabricated in,and to noise generated by digital circuits that operate on the same chip.The impact of this sensitivity is that interface circuits must be custom designed for the process they are implemented in,cannot be easily integrated with their adjoining digital processor,and are often very restricted in their ability to serve a wide variety of applica- tions.The resulting lack of portability of these circuits leads to high development costs since they generally must be redesigned from scratch for new systems. The goal of the proposed research is to develop new interface circuit architectures that can be leveraged over a wide variety of fabrication processes and applications,and thereby dramatically reduce the cost of their implementation in future communication applications.This goal will be achieved by replacing a signi .cant portion of the analog circuitry in the interface with digital circuits that realize the required functionality through signal processing techniques that will be developed as part of this e .ort.This implementation philosophy will lead to dramatically di .erent interface architectures than in use today,and will provide new insights into the tradeo .s between using analog versus digital circuitry for given function and performance requirements. New simulation models and software tools will be developed to facilitate the process of exploring new system architectures and their accompanying circuits.The simulation modeling e .ort will be focused on obtaining accurate behavioral level descriptions of analog components in digital circuit simulators,which will allow straightforward evaluation of the impact of di .erent signal processing algorithms on the overall system performance.The software development e .ort will be directed toward better integrating system level and transistor level simulation tools,and providing estimation of the impact of extrinsic factors such as substrate noise. A new educational course will be developed at MIT that passes on the knowledge and tools ac- quired in this research program.The class will teach high speed circuit techniques for both analog and digital components.System level concepts will be explored through a combination of mathe- matical analysis and interactive numerical simulation using the custom models and software tools. It will examine the impact of circuit limitations on system performance,and explore ways of iter- ating between circuit and system designs to achieve the best overall system performance.Through MIT 's OpenCourseWare initiative,the course materials and software will be made available to other universities as well as industry.Dissemination of the course through the OpenCourseWare program will allow students and industry designers from a variety of ethnic,economic,and geo- graphic backgrounds to have access to state of the art techniques and tools for interface circuit design.