If a circuit is designed with components like R ,L and C then it is called linear circuit.
When sinusoidal signal is applied ,the shape of the signal is preserved at the output with
or without change in the amplitude and shape. But a non-sinusoidal signal alters the
output when it is transmitted through a linear circuit.
The process whereby the form of non-sinusoidal signals such as step, pulse,
square wave, ramp and exponential is altered by transmission through a linear network
is called linear wave shaping.
HIGHPASS RC CIRCUIT
Consider high pass RC circuit as shown in fig.1 below.
Fig.1 Highpass RC circuit
The capacitor offers high reactance at low frequency and low reactance at high
frequency. Hence low frequency components are not transmitted ,but high frequencies are with
less attenuation. Therefore the output is large and the circuit is called a high pass circuit.
Let us see now is, what will be the response if different types of inputs, such as,
sinusoidal ,step, pulse, square wave, exponential and ramp are applied to a highpass circuit., like?
(i) Sinusoidal input
First consider the response of a highpass RC circuit.
R + 1 / jωC
Vo = Vi
Let ω1 =