ANALYSIS AND OPTIMIZATION OF GRID OSCILLATORS

A method for assessing and optimizing the feedback level in a transist or-grid oscillator is presented, Based on the approximate large-signal S-parameters of the transistor, an equivalent circuit model for the g rid is synthesized for maximum oscillator power. The resulting circuit serves as a convenient benchmark for determining the level of feedbac k for a given grid, Experimental results are presented for five differ ent grid oscillators covering S through lia bands. By varying the subs trate thickness and metallization pattern of the grid, the feedback ca n be optimized in accordance with the theory, A grid with an asymmetri c unit cell is shown to deliver almost 60% more effective radiated pow er (ERP) than a grid with a symmetric unit cell.