
22 Feedback Control in Systems Biology
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FIGURE 2.1: O utputs (solid lines) of an LTI system subject to two sinusoidal
inputs (dashed lines) of different frequencies.
with amplitude A, frequency ω (in rad/s) and phase θ (in rad), after an initial
transient we will obtain a stea dy state sinusoidal output signal with the same
frequency
y
∞
(t) = M(ω)A sin(ωt + θ + ϕ(ω)) . (2.7)
It is important to realise that this property does not hold in the g e ne ral
case (i.e. when the system is nonlinear and/or time-varying). Note also that
the amplitude scaling factor and the additional phase ...