chebyshev filter exercise sample

Hi All

I been struggling with the exercise in quotes for the past couple of days and I'm completely stuck!

Any help would be greatly appreciated!

Best regards,

Ericlafesse


"A student who is designing an analogue AM radio receiver has to down-covert the radio-frequency (r-f) signal to an intermediate frequency (i-f) signal. The i-f stage consists of bandpass filter centred around 455 kHz and has a bandwidth of 10 kHz. Within the passband the i-f signal should not be attenuated by more than 1 dB. To ensure that adjacent channel interference is reduced to a minimum the carrier at the adjacent channel must be attenuated by at least 40 dB. If the channel spacing is 10 kHz design the filter that will give adequate selectivity. Give the order of the filter, the transfer function and plot the magnitude response if the student used Chebyshev type II filter in his design."

The most straightforward way to design a bandpass filter is to first design a lowpass filter and then perform a lowpass to bandpass transformation. In your case, the bandwidth would be 455KHz, the bandpass attnuation is 1dB. The stopband attenuation is 40 dB, The stopband frequency is 465 (455 + 10) KHz. These are the parameters required to design the lowpass filter. There are numerous steps involved in designing an inverse Chebyshev lowpass filter. If you have questions on any particular aspect of this, please post or send a private message.