Digital Signal Processing Reference
In-Depth Information
Specifications (10 doubles)
— Contains the sampling frequency in hertz,
followed by the gains and frequencies from the specifications, and finally the
overall filter gain. The gains are specified in decibels and are in the order of
a
pass1
,
a
pass2
,
a
stop1
, and
a
stop2
. The frequencies are specified in hertz and are in the order
of
f
pass1
,
f
pass2
,
f
stop1
, and
f
stop2
.
A coefficients (variable)
— The acoefs written as doubles.
B coefficients (variable)
— The bcoefs written as doubles.
3.7 CONCLUSION
We have now completed the design of a number of analog approximation types
and are able to calculate the frequency response and save the filter parameters for
future use. In the next chapter we'll see how to implement these functions as
active filters. For those interested in the C code used to unnormalize the filter
transfer functions, please turn to Appendix E.
