Comtech EF Data SDR-54A - Manual (Page 49)

SDR-54A Satellite Demodulator Revision 4
Reed-Solomon Option MN/SDR54A.IOM
6.3 Deinterleaver
The unique words inserted by the encoder are used by the decoder to detect the frame
boundary for synchronization of the descrambler and the deinterleaver. The deinterleaver
operates in a similar manner as the interleaver, except that it writes scrambled and R-S
encoded data (with checkbytes) into a static ram in column format, and reads in row
format. The result is data in the original RS code word format. See Figure 6-3 for the R-S
Code Word after deinterleaving.
'RSWORD'
'RSWORD'
n BYTES
k BYTES
OF DATA
2 + t
CHECK BYTES
1 RS PAGE
RS SYNCH
PERIOD
UNIQUE WORD BYTES
GO INTO THESE BYTES
Figure 6-3. R-S Code Word Format
6–3