Texas Instruments C2000

Viterbi, Complex Math, CRC Unit
C2000 Microcontroller Workshop - Viterbi, Complex Math, CRC Unit 11 - 9
32-bit Complex Addition
(a + bj) + (c + dj)
= (a + c) + (b + d)j
VCADD VR5, VR4, VR3, VR2
a
bj
c
dj
VR3
VR2
VR5
VR4
Input 1; VR3: 32-bit real
VR2: 32-bit imaginary
Input 2; VR5: 32-bit real
VR4: 32-bit imaginary
( a + c >> SHR
)
(
b + d >> SHR ) j
VR5
VR4
Result; VR5: 32-bit real
VR4: 32-bit imaginary
Complex Multiply
VCMPY VR3, VR2, VR1, VR0
(a + bj)(c + dj) = ac + bcj + adj + bd(j)
2
= (ac – bd) + (bc + ad)j
a bj
VR0
Input 1; VR0H: 16-bit real
VR0L: 16-bit imaginary
Input 2; VR1H: 16-bit real
VR1L: 16-bit imaginary
c dj
VR1
( ac - bd )
( bc
+ ad ) j
VR3
VR2
Result; VR3: 32-bit real
VR2: 32-bit imaginary