Abstract
A new rigorous iterative process is proposed for studying a rectangular waveguide which includes the Gunn diode GaAs AH445 (THOMSON). It consists in generating a recursive relationship between a given wave source and reflected waves from the discontinuity plane which is divided into cells. A high computational speed has been achieved by using fast mode transformation (FMT). The theory as well as its implemention procedure are described. Numerical results are successfully compared with experimental published data.