During my adventure of designing 433MHz receiver i have recently
discovered
misterious simetrical signal which I am not able to explain to myself. I
am
using USRP1 with WBX daughter board. While observing complex baseband
signal, I realized that depenting on RF gain I have a signal simmetrical
to
the transmitted signal. I have also attached a photo.
[savi_ne@ts-070046nl ~]$ uhd_cal_rx_iq_balance --verbose
linux; GNU C++ version 4.4.6 20120305 (Red Hat 4.4.6-4); Boost_104100;
UHD_003.004.003-221-g9d6f9492
Creating the usrp device with: …
– Opening a USRP1 device…
– Loading FPGA image: /usr/local/share/uhd/images/usrp1_fpga.rbf…
done
– Using FPGA clock rate of 64.000000MHz…
Error: This board does not have the CAL antenna option, cannot
self-calibrate.
– Opening a USRP1 device…
– Loading FPGA image: /usr/local/share/uhd/images/usrp1_fpga.rbf… done
– Using FPGA clock rate of 64.000000MHz…
Error: This board does not have the CAL antenna option, cannot
self-calibrate.
The utilities require transceiver boards like RFX, WBX, SBX. Also
unfortunately, requires FPGA support, which is not in USRP1.
I have USRP1 equipped with WBX and LFTX and LFRX daughter boards. When
want
to use /uhd_cal_rx_iq_balance/ to calibrate my WBX board it won’t do
that,
it says that calibration is not supported by hardware. I suppose the
problem
is uhd wants to calibrate LFRX board, and I don’t know how to specify
the
oder board.
Any suggestions?
