Hey,
I having been trying to debug my demodulator for a few days now
and
in due process i receive the following error message.
ValueError: itemsize mismatch : dbpsk_demod(5):0 using 1, sub_ff(15):0
using 4.
Now there are two things that i observed.
-
With the connect statement of these two at hand , sub_ff is expecting
4
float bytes which is only connected to “1 byte/sample” output by the
dbpsk_demod block. -
The output of the dbpsk_demod block (according to the line – >
io_sig_out = gr.io_signature(1,1,gr.sizeof_char) … so its a
dbpsk_demod_complex->character conversion where as the sub_ff is a
"float
–> float " .
My question is will a custom “gr_dbpsk_demod_cf” with a cosine
function(that possibly uses a certain kind of cosine table) be useful to
do
the following :
- keep the constellation in check (i.e 1 bit/symbol) at 0 and 180
degrees
respectively. - ofcourse convert a complex to float.
- How effective would such a cpp block be as opposed to a full fledged
python block ?
Thanks & regards,
Anay.