(i) (ii) Fig.12. Ambient phase noise performance of i) Reference signal ii) X-band signal
From equation 1 and 2 it is concluded that ~ 38 - 42 dB phase noise degradation factor implies on transforming 100 MHz signal into X-band (8-12GHz) signal. Ambient phase noise performance of reference signal and X-band signal is shown in Fig.12 (i) and (ii) respectively at three offset frequency points i.e. 100 Hz, 1 KHz, and 10 KHz. The reference signal having phase noise of -109 dBc/Hz, -131 dBc/Hz, and -138 dBc/Hz while X-band signal having phase noise of -70 dBc/Hz, -96 dBc/Hz, and -95 dBc/Hz at three offset frequency points respectively.
The phase noise of the signal is very sensitive to any physical disturbance. Random vibration of high g-value affects the phase purity of a piezoelectric material reference source. As reference source clocking PLL any occurrence of phase fluctuation gets directly translated into X-Band signal. Fig. 13(i) and (ii) shows phase noise performance degradation pattern during random vibration of high g-value (7.5g) at an offsets of 100Hz, 1 KHz and 10 KHz for 100MHz and X-band signal respectively. From Fig.13 it is concluded that the phase noise performance significantly degrades as compared to ambient condition at an offsets of 100Hz, 1 KHz and 10 KHz by ~ 50, ~45 and ~15 dB respectively.