Hi,
I am trying to send, then receive and finally display a sinusoid of
arbitrary frequency say 128KHz using two usrp’s and two computers. I
have used grc on both computers to do so.
On tx computer, the flow graph of grc is:
signal source --> usrp sink
In signal source, I set the frequency of cosine wave=128K,
amplitude=10K, offset=0, output type=complex, sample rate=256K. In usrp
sink, I set input type=complex, interpolation=128M/256K=500,
frequency=900M, gain=0dB, side=A, transmit=enable (I am using flex900
daughter boards)
On rx computer, the flow graph of grc is:
usrp source --> scope sink
In usrp source, I use output type=complex, format=16 bits,
decimation=64M/256K=250, frequency=900M, gain=0dB, side=A, RX
antenna=TX/RX, half band filters=enable. In scope sink, I simply choose
the type=complex, sample rate=256K, then all other parameters are
default.
When I run all this, a wave form like tone modulation (amplitude
modulation of a sinusoid with another sinusoid) is displayed on the
scope while I get something displayed on the terminal as:
TX:
A: Flex 900 Tx MIMO B
r.baseband_frequency = 904000000.0
r.dxc_frequency = -4000000.0
r.residual_frequency = 0.0
r.inverted = False
RX:
A: Flex 900 Rx MIMO B
r.baseband_frequency = 896000000.0
r.dxc_frequency = -4000000.0
r.residual_frequency = 0.0
r.inverted = False
And when I stop the simulation on tx computer, a sinusoid waveform of
frequency about 4.4 KHz is displayed on rx computer. Can anyone please
suggest something in this regard?
Thanks,
Mahboob