[Discuss-gnuradio] Interleaving

[Daniel Estévez]

Hi all,

I have a stream of complex samples

x_{11}, x_{12}, ..., x_{1N}, x_{21}, x_{22}, ...., x_{2N}, ...., x_{M1},
x_{M2}, ..., x_{MN}.

What I want to do is to compute the FFT's of

x_{11}, x_{21}, ..., x_{M1}

x_{12}, x_{22}, ..., x_{M2}
.
.
.
x_{1N}, x_{2N}, ..., x_{MN}

To achieve this, I can deinterleave my stream into N streams, and then
for each of these N streams put a vector to stream block with M items
and an M point FFT, followed by an interleave of the N streams.

However, there must surely be a more intelligent way to do the same
thing with fewer blocks, probably using vectors, but I don't know how to
do it.

The intended application of this is Pulse-Doppler processing:
https://en.wikipedia.org/wiki/Pulse-Doppler_signal_processing#Filtering
A similar procedure is done when interleaving data packets, to prevent
burst errors from corrupting adjacent bytes. Surely someone has needed
to do this operation before.

Best regards,

Dani.