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

3 8th Harmonic Oscillator
Fig. 3.10: Measured output signal around the 8th harmonic signal (8f 0 ) (6 dB SMA
connector loss in V -band is included).
connector around the 50 GHz. The operating drain bias voltage is 3.9 V. The bias current
is 100 mA. The phase noise is -93 dBc/Hz at the offset frequency of 1-MHz and -69 dBc/Hz
at the offset frequency of 100-kHz. Figure 3.11 shows the measured output power spectrum
of undesired harmonics (f 0 ∼ 7f 0 ). Measured undesired harmonic signals are from -12.17
dBm (at 2f 0 ) to -47.67 dBm (at 7f 0 ). Table 3.2 shows the output performance of the
8th harmonic signal. Table 3.3 shows the detail measured output power of undesired
harmonics shown in Fig. 3.11. The output power of even harmonics are higher than odd
Table 3.2: Measured output performance at 8f 0
Frequency (8f 0 )
50.96 GHz
Output power (estimated) -6.33 dBm
Phase noise (1-MHz offset) -93.0 dBc/Hz
Phase noise (100-kHz offset) -69.5 dBc/Hz
harmonics because harmonic injection power is very small at the odd harmonics. The
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