Strange OFDM behavior with CCSDS encoding

Right now I’m messing around with OFDM in grc, and I made an extremely
simple system, where I have an input text file to an OFDM modulation
to an OFDM demodulation to a file sink. Obviously this setup works
fine, outputting a text file pretty much the same as the input text
file.

However, when trying to add error correction code, the ODFM
demodulation never outputs any values. Right after the input file
source, I add an ‘Encode CCSDS 27’ block, which then is connected to
an OFDM mod block, and a ‘Decode CCSDS 27’ block is added after an
OFDM Demod block. What could be the cause of this? To my knowledge,
the OFDM modulation and demodulation code does not care about what
‘kind’ of input bytes there are, as long as there isn’t something
weird happening between the OFDM mod and OFDM demod. The problem
isn’t with the error correction code either, as (according to a number
sink) no values are ever being passed to the decode ccsds block.

Also, all of my options for the OFDM mod and demod is the defaults.

Again, here is my setup:

File Source(bytes) -> Encode CCSDS 27 (bytes to bytes) -> OFDM Mod
(bytes to complex) -> OFDM Demod (complex to float) -> Decode CCSDS 27
(float to bytes) -> file sink (bytes)

-Trevor

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