On Which Factors Cut Off Frequency Of Rectangular Low Pass Filter Depends

Hi Abdullah,

In general, the cut-off frequency of any low-pass filter depends on 2 parameters: internal resistance and its capacitance. Rectangular filter is considered as an ideal filter in this case, I think.

This cut-off frequency defines the passband of your signal. Your bit rate will be defined by signal bandwidth and type of coding you are using.

The Bessel filter transfer function depends on two factors of insertion loss and order parameter of a normalizing constant. While the transfer function of a rectangular filter depends also on the insertion parameter, depth parameter, a center frequency and bandwidth.
It is interesting to note that in the “help” of the Bessel filter he makes an important observation:
Important: Previous versions older than OptiSystem 7.0 used a different equation to estimate the 3 dB bandwidth. The following table provides the multiplication factor that has to be multiplied by the current bandwidth in order to obtain the same results of versions older than OptiSystem 7.0:
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Heitor Galvao is right i endorsed his views.

Abdullah Baig
May I know which type of work you are doing on RoF link. Can be share it