[Discuss-gnuradio] base band signal sample frequency in RFX 900 daughter board

[pengyu zhang]

Hi,

I use USRP1 and RFX 900 daughter board to receive an 925MHz signal. The receiver configuration code is shown below. Some people told me that the RFX 900MHz board will do down conversion and convert the 925MHz signal to a base band signal automatically. Can you tell me what is the frequency to sample the base band signal? I cannot figure it out according to the following code. Thanks.

Receiver's configuration code:

rx = usrp.source_c(0, dec_rate, fusb_block_size = 512, fusb_nblocks = 8)
rx_subdev_spec = (1,0)
rx.set_mux(usrp.determine_rx_mux_value(rx, rx_subdev_spec))
rx_subdev = usrp.selected_subdev(rx, rx_subdev_spec)
rx_subdev.set_gain(rx_gain)
rx_subdev.set_auto_tr(False)
rx_subdev.set_enable(True)
r = usrp.tune(rx, 0, rx_subdev, freq)

Pengyu