Improvement on the diagonal routing model

The authors study a new channel routing model, called the diamond model (DDM), whose grid is composed of right tracks with slope +60° and left tracks with slope -60° on two layers. We show that any two-terminal (multiterminal) channel routing problem (CRP) can be solved in a channel of width less than 4d (9d) with all vias at a distance no less than one. This result is important both from a theoretical and from a practical point of view. It improves the result obtained by Lodi et al. (Technical Report TR-22/91, University of Pisa, 1991)