## 5 Simulation and Validation
The total harmonic distortion (THD) of the filter for LP and BP responses is plotted for different input signal amplitudes for VM as shown in Table 6.5 The THD plot for CM-BP/LP is presented in Table 6.6 The THD remains within acceptable limits (\(\leq\)7.5%) for appreciable input range. Table 6.7 VM MISO configuration: (**a**) the Monte Carlo analysis results for BP response and (**b**) the corresponding histogram. Table 6.8 VM MISO configuration: (**a**) phase responses and (**b**) pole frequency tuning for different OTA bias current values for AP response. tance are the threshold voltage (\(V_{t}\)) and carrier mobility. \(V_{t}\) can be approximated as a linear function of temperature [45,46] given by Equation (38):  
Table 6.9  
here, \(\alpha_{Vt}\) denotes the threshold voltage temperature coefficient which, varies from \(-1\) mV/\({}^{\circ}\)C to \(-4\) mV/\({}^{\circ}\)C and \(T_{O}\) is the reference temperature (300 K). The dependence of carrier mobility on temperature is modelled by [46]:  
Figure 6:0  
where \(\alpha_{\mu}\) is the mobility temperature exponent considered as a constant approximately equal to 1.5. The Equations (38) and (39), show that the threshold voltage (\(V_{t}\)) and mobility (\(\mu_{N}\)) exhibit a negative temperature dependence which explains the decrease in frequency with temperature, as shown in Figure 18 for CM AP response. To validate the proposed CM-SIMO filter, it is designed for a center frequency of 6.4 MHz and quality factor of 1.015 by selecting passive component as \(R_{1}=R_{2}=2\) k\(\Omega\), \(C_{1}=C_{2}=20\) pF and \(g_{m1}=1.0321\) mS. The five filter responses in CM mode are presented in Figure 6:1  
Figure 6:2 CM SIMO configuration: (**a**) frequency responses of the LP, BP, HP and BR filter and (**b**) gain and phase responses of the AP filter. Figure 6:3 CM MISO configuration: variation of filter pole frequency with temperature and percentage of deviation from the designed frequency for AP response. The time domain and Monte Carlo analysis results of the filter are presented in Figures 20 and 21, which verify the correct filter operation. The histogram depicted in Figure 21 demonstrates the variations of the pole frequency at \(-180^{\circ}\). The \(Q\) factor tunability is tested for different values of resistor \(R_{2}\), as presented in Figure 6:4 The fitting equation using a linear regression with \(R^{2}\) = 0.9986 is given in Figure 22b. Furthermore, the total harmonic distortion for different input current amplitudes is shown in Figure 6:5 It can be inferred that the THD remains approximately 2.5% for a considerable signal range. Figure 6:6 CM SIMO configuration: the Monte Carlo analysis results for AP configuration. Figure 6:7 CM SIMO configuration: transient analysis results for LP, HP and BP filter configurations. It can be concluded from the results that the characteristics of the AP filters have a slight imperfection, as all magnitude responses have a hump at the resonant frequency. This is caused by the frequency-dependent non-ideal current and voltage transfer gains and the parasitic resistances associated with the different nodes. All the mentioned non-idealities are discussed in detail in Section 4. It is also found that the linear range (dynamic range) of the circuit is mostly affected by small supply variations; however, the filter performance is not adversely affected. To further bring out the merits of the proposed filter, a comparative analysis of the single ABBs-based mixed mode filters is carried out. It can be inferred from Table 7 that except [40], no other filter can provide all five filter responses in all four modes of operation. The latest presented filter in [47] is not a truly mixed mode and also suffers from use of negative and double input signals for filter response realization. The designs in [14; 27; 40; 48] suffer from passive component matching requirements. The design in [48] requires a change in circuit configuration for realizing different responses, which is impractical.