Traveling wave amplification in distributed IMPATT diodes

The current work incorporates the IMPATT mechanism into the traveling wave model and considers the actual carrier field interaction. The resulting propagation constant as a function of frequency and bias current density is documented. The diode as an oscillator is discussed together with the oscillation and frequency conditions. A 3-section quarterwave transformer is suggested to provide the impedance step between the low diode impedance and the external 50 omega circuit. A perturbational estimate of the wave losses in the substrate and the p + or - layer indicates that the substrate thickness must not exceed one skin depth in order to keep the losses small with respect to the gain. An approximate equivalent transmission line model is found whose shunt admittance is equal to the distributed admittance of a discrete diode.