Figure 2-2 shows a block diagram of the 3 × pre-multiplier stage using the TRF37C75 amplifier. Figure 2-3 compares the phase-noise performance of the pre-multiplier stage with that of the signal generator. Table 2-2 reports the integrated jitter performance for each configuration.

Figure 2-3 Phase-Noise Comparison of 1474.56-MHz Signal

As expected, the SMA100B provides the best output at 1474.56 MHz. The 3 × multiplied Wenzel oscillator performance is also quite good. The sweep of the SMA100B is nearly identical to the ideal response when the input performance is degraded by 20 × log (n), where n = 3 as the multiplication factor. As before, the multiplied-up Wenzel approach is significantly better than the Agilent PSG.