I just started learning signal processing and one of the very first topics I begun with is convolution. I want to learn signal processing practically, therefore I opted to work with circuits(also a newbie in this) in parallel.
In the first exercise I did, there is a piecewise linear function which I convolved with RC circuit(once by grounding capacitor(0.1 μF) and the other time by grounding resistor(10 kOhms)). The experiment is divided into two parts.
I did circuit simulation in multisim and applied transient analysis to understand the convolution.
- Using hardware measurement with NI myDAQ
I used NI ELVIS waveform generator to generate the signal to the circuit and NI ELVIS oscilloscope to graph the output and input to the RC circuit. I have attached both the transient analysis and oscilloscope graphs of low pass and high pass filtered output. After completing the experiment, I got few questions.
- How well the input signal(amplitude of 5V) affects when I increase/decrease capacitance and/or resistance in the circuit?
- In the simulation, the amplitude of filtered low pass signal is around 4.8 V whereas on real circuit, the amplitude is around 1 V. Could that be any mistake of mine or do the real circuit cause such high voltage drop? Or any other factors?
- Also the waveforms in both cases look different. Especially in the high pass filter circuit, the waveform is in negative side. How should I understand this? If there is any underlying explanation that I need to know, it would really be helpful to understand the concept better. Thank you in advance.