I am aware that GNURadio doesn't support feedback
loops in the flow graph. However, I have an application scenario
where every execution of a GRC block, I need some of the
previous outputs of that block.
For example, if I have a block called A which produces
y0,y1 and consumes i0, i1. Assume all input/output buffers are
of size d. Also assume the block implements some signal
processing function, y0[n] = x(i0[n], i1[n]) and y1[n] =
y(i0[n]) where 'x' and 'y' are some arbitrary functions that
the GRC block implements. i0 is some BPSK independent source.
i1 is the delayed output y1. In other words, i1 = y[n - d].
In the flow graph, y1 will go through a delay block and
become i1 to the GRC block. However this creates a feedback
loop in the flow graph.
How do I go about implementing such a scenario?
A few solutions I have read online say that all feedbacks
can be done internal to the custom block. The problem i have
is that my application will no longer be real time.
Ideally I would like to have the block process a sample
size of 'd' at a time where a USRP board dumps the BPSK stream
in real time.
Any pointers?
Vipin