High Order Harmonic Oscillators in Microwave and Millimeter-wave ...

3 8th Harmonic Oscillator
impedance of the microstrip ring resonator including the output circuit at the port 1 and
port 2 shown in Fig. 3.5. The impedance is simulated by the ADS momentum. The
port impedance of the input ports (port 1 and port 2) is terminated by 84 Ω as same as
the characteristic impedance of the gate port. The output port is terminated by a 50 Ω
impedance.
Fig. 3.7: Simulated input impedance characteristic of negative resistance circuit.
150
Impedance (Ω)
100
50
0
-50
4.0
4.5
real Zin
5.0
5.5
imag. Zin
6.0 6.5
7.0
7.5
8.0
Frequency (GHz)
Fig. 3.8: Simulated input impedance characteristic of the microstrip ring resonator and
the output circuit.
35