BRUEL & KJAER 1615 - 6 Useful Filter Information and Definitions; Ideal Filter (Band-Pass)

6. USEFUL FILTER INFORMATION AND DEFINITIONS
IDEAL FILTER (BAND-PASS)
An ideal bandpass filter is one which displays zero attenuation in the pass
band and infinite attenuation at any other frequency.
i.e. If the pass band extends from f1 to f2,
c
0
" iii
a=O
and a= oo
- ~ 0. 4t - +---+-- +-+-
UI
c
_g 0.3 t--+- --+- -++--
~
~ 0.2 t- --+-- - +----1+-
&!
- Frequency
fo
!M968
Fig.6.1 Concept of Effective Bandwidths and Ideal Filter
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