On Sun, Apr 16, 2006 at 03:28:51PM -0400, Dawei Shen wrote:
As far as know, Flex 400 only has a single subdevice.
single subdevice for Tx, single subdevice for Rx.
The Flex daughterboards look like two distinct pieces of h/w to the
s/w. They have separate LO’s, etc.
How do you use one Flex400 daughter card for both transmission and
reception at the same time? Do you mean I use only one antenna using
the TX/RX port, or I use two antennas with one using Rx2 for
reception and the other using TX/RX port for transmisson?
If you are transmitting and receiving full duplex (simultaneously),
you’ll need to use TX/RX for transmit and RX2 for input (and you’ll
need to be TXing and RXing at pretty widely separated frequencies,
and/or use a diplexer).
The rx subdevice class has a method for selecting which antenna port
to use for reception:
def select_rx_antenna(self, which_antenna):
Specify which antenna port to use for reception.
@param which_antenna: either 'TX/RX' or 'RX2'
if which_antenna in (0, 'TX/RX'):
self._u.write_io(self._which, 0, RX2_RX1N)
elif which_antenna in (1, 'RX2'):
self._u.write_io(self._which, RX2_RX1N, RX2_RX1N)
raise ValueError, "which_antenna must be either 'TX/RX' or
If you’re not transmitting and receiving at the same time, you can use
the single Tx/Rx port for both, along with Auto T/R mode
self.subdev.set_auto_tr(True) # must execute on both the Rx and Tx