An improved nonlinear analysis and design method of microstrip oscillators based on modern CAD techniques

In this paper, a novel nonlinear oscillator design methodology is proposed to obtain an improved microstrip oscillator performance. It combines the advantages of both quasi-linear and nonlinear design approaches. It uses an accurate implemented nonlinear MESFET model, based on multi-bias measurements. It also uses an enhanced harmonic balance nonlinear analysis technique. This design method makes full use of the powerful capabilities of the up-to-date CAD techniques in designing, simulating, and optimizing microstrip oscillators, taking all discontinuities, parasitics and packaging effects into consideration. It specifically uses the HP Microwave Design System (HP-MDS). Finally, an 8.5 GHz oscillator is fabricated and an excellent agreement between the theoretical and experimental results is obtained