Thank you for your kind help to my questions.
I am developing a satellite beacon receiver of
150/400MHz. Now I am receiving both signals by
using Basic RX (150MHz) and FLEX400 (400MHz) boards.
I am happy so far.
I have some more questions for further development.
(1) File format
I record signals into files. I want to read them
for analysis. What is the data format written/read
by file_sink() / file_source()? I am recording
complex signals in the files.
(2) “O” “U” “u” “a”
These characters appear on the screen when I run
my program. I understand they appear when data flow
from USRP to PC is stopped or something. I am curious
what are the meaning of these characters. Does faster
PC help reducing such data flow troubles?
(3) Signal coherence … (a)
I need to keep signal coherence between 150MHz and 400MHz.
I should run the FLEX400 board at the same timing to the
USRP main board. I found the following information URL
Is this instruction still valid? I am using USRP ver4.
(4) Signal coherence … (b)
I have one more question on the signal coherence. In my
program I keep the same sample speed and the same FIR filter
for both 150MHz and 400MHz. (Sure I am using a “deinterleaver”
to separate the signals.) Can you guarantee signal coherence
in the GNUradio data flow?
Mamoru Y. firstname.lastname@example.org