New Design Approach for Wide-Band FET Voltage-Controlled Oscillators

The frequency tuning characteristics of transistor voltage-controlled oscillators with distributed parameters

“…As a character of curves in Figure 8(a) does not change depending on the value of a load and only the displacement of zeros and poles are taken place, the calculation of a step discontinuity in#uence can be done for the case of short-circuited two-section line. Then in consideration of equation (14) the expression for input reactance Z can be written as From equation (15) it follows that a value of "rst zero "0 and a value of "rst pole can be de"ned from the following transcendental equation:…”

“…So, a parameter optimization of the MESFET VCO oscillation system with T-transformer between the gate and Figure 13. Frequency dependences of normalized input impedance of a loaded two-port network consisting of coupled transmission lines varactor has contributed to realize a nonlinearity extent "1.5 at varactor frequency tuning bandwidth of 7}10 GHz [14]. An advantage of such a resonant circuit con"guration is the varactor and transistor base or gate electrodes DC grounding without additional radio-frequency chokes.…”