You should probably use an add block instead of Streams to Stream.
Here's an example flow graph.
http://www.w6rz.net/pfb-filter-10.grc
Ron
On 12/21/20 11:20, George Edwards wrote:
Hello,
I have three signals routed to the Gnuradio Polyphase Channelizer
Block. The system operates at a sample rate of 90 kHz with 3 channels
spaced 25 kHz apart. One channel is centered around DC and the other
two at +/-25 kHz. The 3 waveforms are routed into a Gnuradio Streams
to Stream Block, so that a simple concatenated stream flows into the
Gnuradio Polyphase Channelizer. I also set the Channelizer Block to
use 120 Taps and provide 3-outputs. Here are my questions on observing
the outputs
Q1. I was expecting each output (block set to 3 outputs) to be at the
sample rate (90 kHz/3 =) 30 kz in each of the 3-plots. The plots show
a sample rate based on the original rate of 90 kHz. Why is this?
Q2. I expected each output waveform to be centered around DC, but they
were instead centered around -25 kHz. Why?
Q3. The output bandwidth for each waveform seems a little bigger than
the input, why?
I will appreciate any help that assists to point me in the right
direction.
Regards,
George
