I implemented basic bandpass filter using [Scipy resource][1]. But how to implement the same when signal is centred at non-zero centre frequency with centre frequency > sampling frequency. I trying to implement bandpass filter as current code throws error > ValueError: Digital filter critical frequencies must be $0 \le \omega_n \le 1$ which clearly makes sense. **Example:** - Centre frequency: $100\textrm{ MHz}$ - Sampling frequency: $5\textrm{ MHz}$ - Highcut: $102\textrm{ MHz}$ Clearly (highcut/nyq) > 1 [1]: http://scipy.github.io/old-wiki/pages/Cookbook/ButterworthBandpass