Re: [Discuss-gnuradio] Poly phase channelizing in Blade Or USRP

[Sylvain Munaut]

Hi,


> It seems like a perfect fit for a poly phase filter - however this is
> something that I believe needs to be done in hardware (128 channels *
> 200khz = about 60mhz sample rate this will not go over a USB cable, and
> I doubt I can get this bandwidth into a laptop PC.

!?!?

128 channels of 200 kHz = 25.6 MHz of bandwidth. You can totally get
that to a laptop.
B2xx or BladeRF will do that without issues given a sufficiently good laptop.
Even a hackRF with USB2 only can nearly do it ( 20 MHz ).

If the transmission are "infrequent" you can even use the same trick
that researchers used a while back to listen to all of bluetooth and
deliberately alias the signal to fold the spectrum over itself.


>     Am I going to have to do FPGA work on my own?

Very likely.


>     Or - is there some existing cook book solution with the FPGA
> configuration pre-cooked?

Very unlikely to find something "all done".
Especially that if you don't want to ship the samples, a PFB is not
all you need. You'd need demod for each channel in the hardware as
well.


> What I am looking for is the FPGA channelizer solution... hopefully an
> existing one I could start with?

There is an embryon of one in the ettus rfnoc repo and AFAIK they
might also replace it with another version soon.

But it's written for RFNoC and Series-7 Xilinx fpga. It'll need quite
some adaptation to run on anything else.
Also, AFAIU, it's incomplete and non-tested currently so ... YMMV.


Cheers,

    Sylvain