A CAD tool for electromagnetic simulation on the associative string processor

The associative string processor (ASP) is a scalable fine grained SIMD architecture, optimized for image processing tasks. In this paper the authors describe a new application for this available architecture. The finite different time domain (FDTD) method is a technique used to solve electromagnetic boundary value problems. The technique produces results in the time domain which can then be post-processed using Fourier transform techniques to obtain the steady state frequency response. In order to obtain high frequency responses a large number of time steps must be used which requires a large amount of computational effort. The excessive execution time required when using sequential computing architectures has precluded its use as part of an iterative design flow until now. On an example problem the execution time on the ASP, with a 20 MHz clock frequency, was found to be 25 minutes, compared with the 12 hours required for a VAXstation 3500 implementation. Moreover, the execution time rises only slowly with the problem size and the mapping technique is not problem dependent