Dear all
I have two debian host PCs and two USRPs. I have been trying to measure
Channel Impulse Response using usrpsounder.py.
My command lines are as follows:
./usrp_sounder.py -f 2.4G -r -v -D -F output.dat
./usrp_sounder.py -f 2.4G -R A -t -v -D
I then used
 a=read_complex_binary.m
 plot(abs(a))
to see the result. I am consistently getting zero values all the time.
My output lines are as below:
gnuradio:/home/gnuradio/gnuradio/gr-sounder/src/python#
./usrp_sounder.py -f 2.4G -R A -t -v -D
Using PN code degree of 12 length 4095
Sounding frequency range
is 2.384G to 2.416G
db_xcvr2450_tx: init
Creating new xcvr2450 instance
xcvr2450: init with 47a50364: 0
Using XCVR2450 Tx for sounder transmitter.
Asserting reset.
Writing mode register with: 0x1
Setting transmitter frequency to 2.4G
Setting PN code degree to 12
Disabling digital loopback.
Writing mode register with: 0x1
De-asserting reset.
Writing mode register with: 0x0
Enabling transmitter.
Writing mode register with: 0x2
Press return to exit.^CTraceback (most recent call last):
 File “./usrp_sounder.py”, line 112, in
   main()
 File “./usrp_sounder.py”, line 109, in main
   raw_input(“Press return to exit.”)
KeyboardInterrupt
Disabling transmitter.
Writing mode register with: 0x0
xcvr2450: del
gnuradio:/home/gnuradio/gnuradio/gr-sounder/src/python#
melag:/home/mutsag/gnuradio/gr-sounder/src/python# ./usrp_sounder.py -f
2.4G -r -v -D -F output.dat
Using PN code degree of 12 length 4095
Sounding frequency range is 2.384G to 2.416G
Logging impulse records to file:Â output.dat
db_xcvr2450_rx: init
Creating new xcvr2450 instance
xcvr2450: init with 48571832: 1
xcvr2450: Setting reg 2 to 030072
xcvr2450: Setting reg 5 to 038885
xcvr2450: Setting reg 6 to 004006
xcvr2450: Setting reg 7 to 000627
xcvr2450: Setting reg 8 to 01C218
xcvr2450: Setting reg 9 to 0068B9
xcvr2450: Setting reg 10 to 003C0A
xcvr2450: Setting reg 11 to 00010B
xcvr2450: Setting reg 12 to 0003FC
RF=2.45G VCO=3.26667G R=1 PHD=21.3333M DIV=153.12500 I=153 F= 8192
ACT=2.45G
GPIO: RXRX=6000 RXTX=4000 TXRX=E010 TXTX=A810
xcvr2450: Setting reg 3 to 000993
xcvr2450: Setting reg 4
to 008004
xcvr2450: Setting reg 5 to 038825
lock detect: True
Using for sounder receiver.
Setting receiver gain to None
Generating impulse vectors of length 4095 byte length 32760
Using smoothing alpha of 1.0
Asserting reset.
Writing mode register with: 0x1
Setting receiver frequency to 2.4G
Setting PN code degree to 12
Disabling digital loopback.
Writing mode register with: 0x1
De-asserting reset.
Writing mode register with: 0x0
Writing mode register with: 0x4
Starting receiver flow graph.
gr_buffer::allocate_buffer: warning: tried to allocate
  4 items of size 32760. Due to alignment requirements
  512 were allocated. If this isn’t OK, consider padding
  your structure to a power-of-two bytes.
  On this platform, our allocation granularity is 4096 bytes.
gr_buffer::allocate_buffer: warning: tried to allocate
 Â
4 items of size 32760. Due to alignment requirements
  512 were allocated. If this isn’t OK, consider padding
  your structure to a power-of-two bytes.
  On this platform, our allocation granularity is 4096 bytes.
Enter CTRL-C to stop.
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Received impulse vector of length 32760
Stopping receiver flow graph.
Waiting for threads…
Receiver flow
graph stopped.
Writing mode register with: 0x0
xcvr2450: del