III. Gm-C Filtering - Epublications - Université de Limoges

Furthermore, the high sensitivity to process and mismatch issues of the MGTR
technique is illustrated in Figure 132. This figure depicts the Monte-Carlo simulation results
of the Gm-cell IIP3. It appears that the mean value is 19.8dBm, which is the targeted value.
However, the standard deviation describes a high dispersion for 100 runs, since σ=1.5dBm.
The dispersion and the sensitivity to PDA bias of each Gm-cell will result in a very sensitive
filter. Robustness already appears as a limiting issue.
Figure 132. Monte-Carlo Simulations of the Gm-cell IIP3 for 100 runs
III.3.c.ii Filter Performances
The tuning range of Filter1 covers the full 45 to 450MHz band. A constant Q-factor of
4 is depicted in Figure 133 and guarantees a minimal harmonic rejection. Figure 134
represents the evolution of the central frequency versus the capacitance provided by the
capacitor banks.
Figure 133. Filter Gain and Q-factor for various central frequencies
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