Add support to set Rx/TxAntenna

Some devices have different Rx or Tx ports with different RF characteristics.
For instance LimeSDR has H (High), L (Low) and W (Wide) band Rx ports,
each of one being more suitable to a specific range of frequencies.

In case one wants to support several GSM bands, the best option is to
use the WideBand port and connect the antenna physically to that port in
the board. Then the firmware must be instructed ro read from that port.
Support for Rx/Tx port configuration is already in there for all the
layers (Limesuite, SoapySDR, SoapyUHD, UHD), but we are missing the
required bits in osmo-trx to make use of the available UHD API. This
commit addresses it.

Before this patch, the Rx/Tx paths configured could be changed by means
of the LimeSuiteGUI app, but after running osmo-trx, the values were
changed to the default ones.

One can now start using osmo-trx with 1 channel and specific Rx/Tx ports
by using for instance: osmo-trx -c 1 -y BAND1 -z LNAW

Default behaviour if no specific path or an empry path is passed ("") is
to do the same as preiously, ie. nothing by not calling the
set{T,R}xAntenna APIs.

One can also configure only specific channels, for instance to configure
only the first Tx channel and the second Rx channel:
osmo-trx -c 2 -y BAND1, -z ,LNAW

Change-Id: I1735e6ab05a05b0312d6d679b16ebd4a2260fa23

1 files changed, 12 insertions, 0 deletions

diff --git a/Transceiver52M/USRPDevice.h b/Transceiver52M/USRPDevice.h
index 3cbf672..f5fbe85 100644
--- a/Transceiver52M/USRPDevice.h
+++ b/Transceiver52M/USRPDevice.h
@@ -179,6 +179,18 @@ private:
   /** return minimum Rx Gain **/
   double minTxGain(void);
 
+  /** sets the RX path to use, returns true if successful and false otherwise */
+  bool setRxAntenna(const std::string &ant, size_t chan = 0);
+
+  /* return the used RX path */
+  std::string getRxAntenna(size_t chan = 0);
+
+  /** sets the RX path to use, returns true if successful and false otherwise */
+  bool setTxAntenna(const std::string &ant, size_t chan = 0);
+
+  /* return the used RX path */
+  std::string getTxAntenna(size_t chan = 0);
+
   /** Return internal status values */
   inline double getTxFreq(size_t chan = 0) { return 0; }
   inline double getRxFreq(size_t chan = 0) { return 0; }