Pentek 6210 Operating Manual page 66

HALFBAND
FILTER INPUT
F = f
N S
CONTROL WORD 7, BIT 15
F = F
N HB1
CONTROL WORD 7, BIT 16
F = F
N HB2
CONTROL WORD 7, BIT 17
F = F
N HB3
CONTROL WORD 7, BIT 18
F = F
N HB4
CONTROL WORD 7, BIT 19
†
Each halfband section decimates by 2.
FIGURE 17. BLOCK DIAGRAM OF HALFBAND FILTER
SECTION
3-18
f = f
IN S
HALFBAND FILTER 1
0
1
F = f OR f
HB1 S
HALFBAND FILTER 2
0 1
F = F OR F
HB2 HB1
†
HALFBAND FILTER 3
0
1
F = F OR F
HB3 HB2 HB2
†
HALFBAND FILTER 4
0 1
F = F OR F /2
HB4 HB3 HB3
†
HALFBAND FILTER 5
0
1
F = F OR F /2
5 HB4 HB4
HALFBAND
FILTER OUTPUT
HSP50214B
0
-6dB BANDWIDTH
-20
†
-40
-60
/2
S
-80
†
-100
/2
-120
HB1
FIGURE 18. HALFBAND FILTER FREQUENCY RESPONSE
/2
0
ALIAS
PROFILES
-20
-40
-60
-80
-100
-120
FIGURE 19. HALFBAND FILTER ALIAS CONSIDERATIONS
HALFBAND FILTER 5
HALFBAND FILTER 4
HALFBAND FILTER 3
HALFBAND FILTER 2
HALFBAND FILTER 1
0.125 0.25
NORMALIZED FREQUENCY (F
N
-6dB BANDWIDTH
HALFBAND FILTER 5
HALFBAND FILTER 4
HALFBAND FILTER 3
HALFBAND FILTER 2
HALFBAND FILTER 1
0.125 0.25 0.375
NORMALIZED FREQUENCY (F
0.375 0.5
)
0.5
)
N