Constraint Modules: An Introduction
I describe a methodology for solving convex constraint problems
using analog circuits. I demonstrate how this methodology can be
used to design circuits that solve function-fitting problems through
iterated gradient descent. In particular, I show how to build a
compact circuit that can model a nonlinearity by observation, and
predistort to compensate for this nonlinearity. The system fits into
a broader effort to investigate non-traditional approaches to
circuit design. First, it breaks the traditional input-output
abstraction barrier; all ports are bidirectional. Second, it uses
primarily local properties of the circuit to show stability. Such
stability arguments can be scaled to much more complex systems than
traditional stability criteria.
The following are available:
- The IEEE ISCAS 2008
paper. This is somewhat limited due to space limitations.
- My Ph.D Thesis
contains the same material as in the paper, but in much greater
detail.
- My thesis defense was the same talk
as I delivered at ISCAS, but much longer and more detailed. This
is a good place to start. (warning: 362MB video file). You can
also look at the defense slides.
- The slides from my talk at IEEE ISCAS
'08 (these may have changed slightly for the final talk -- posted
several days prior).
If you have any questions or comments, please contact me.