I believe the GRC “Simple Correlator” is the inverse of the “Simple
Framer,” yet it takes float inputs. What is the proper format of the
input data? I see that the code does some slicing on the input, so I
expect the floats to be positive and negative float values representing
ones or zeros respectively.
Asked another way, what is wrong with the simple flowgraph below?
File Source (byte) ->
Simple Framer (Payload Size = 6) ->
Packed to Unpacked (Byte,1 bit per Chunk, MSB) - This block
causes the bits to be represented as serial bytes. ->
Char to Float (scale 1) ->
Add Const (float, -0.5) This removes the DC bias to
facilitate slicing. ->
Simple Correlator (Payload Byte Size = 6) ->
File Sink (byte).
No data comes out of the Simple Correlator, but using GUI sinks, I see
that all the other blocks work.
There is mention on the Internet that the Simple Correlator requires 8x
oversampling. Is that true? I only need correlation at the bit level,
not at the symbol timing. Is the Simple Correlator the wrong block to
undo the Simple Framer?