RF Electronics Chapter 6: Oscillators Page 203
2022, C. J. Kikkert, James Cook University, ISBN 978-0-6486803-9-0.
placing a small capacitor at a strategic location along the feedback path. Then the lengths
of TL13 and TL2, the resonator spacing Sc1 and the values of the terminating resistors
R1 and R2 in figure 6.46 are tuned, to obtain the correct resonator frequency, the correct
phase for OSCTEST and a high group delay.
For both the oscillators, the effect of external loads was reduced by inserting a 150 Ω
resistor in series with the oscillator output. The resulting reduction in output signal can
easily be made up using an additional MMIC.
Figure 6.52. Comparison of improved single and dual resonator oscillator OSCTEST results.
Figure 6.53. PCB layout for the improved 1GHz single resonator oscillator.
Figures 6.52 shows the OSCTEST loop gain and phase for both the improved single and
dual resonator oscillators. Comparing this with figure 6.49 shows a narrower bandwidth,
RF Electronics: Design and Simulation
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