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+== OsmoTRX hardware device support
+OsmoTRX consists of a _common_ part that applies to all TRX devices as well as
+_hardware-specific_ parts for each TRX device. The hardware-specific parts are
+usually provided by vendor-specific or device-specific libraries that are then
+handled by some OsmoTRX glue code presenting a unified interface towards the
+rest of the code by means of a _RadioDevice_ class.
+The common part includes the core TRX architecture as well as code for
+implementing the external interfaces such as the TRX Manager UDP socket,
+control, and VTY interfaces.
+The hardware-specific parts include support for driving one particular
+implementation of a radio modem. Such a physical layer
+implementation can come in many forms. Sometimes it runs on a general
+purpose CPU, sometimes on a dedicated ARM core, a dedicated DSP, a
+combination of DSP and FPGA.
+Joining the common part with each of the available backends results in a
+different binary with different suffix for each backend. For instance, when
+OsmoTRX is built with UHD backend, an _osmo-trx-uhd_ binary is generated; when
+OsmoTRX is built with LimeSuite backend, an _osmo-trx-lms_ binary is generated.
+Build of different backend can be enabled and disabled by means of configure
+flags, which can be found in each subsection relative to each backend below.
+=== Ettus USRP1
+The binary _osmo-trx-usrp1_ is used to drive this device, see <<backend_usrp1>>.
+=== Ettus B200
+The binary _osmo-trx-uhd_ is used to drive this device, see <<backend_uhd>>.
+Comes only with 1 RF channel. It can still be used in a multi-TRX setup by using
+the <<multiarfcn_mode>> feature. By using this feature, one can drive up to 3
+TRX (with the restrictions explained there).
+=== Ettus B210
+The binary _osmo-trx-uhd_ is used to drive this device, see <<backend_uhd>>.
+Comes with 2 RF channels, which can be used to set up a multi-TRX BTS. However,
+due to a shared local oscillator for both RF channels, ARFCN separation can be
+up about 25 MHz.
+This device also supports the <<multiarfcn_mode>> feature. By using this
+feature, one can drive up to 3 TRX (with the restrictions explained there).
+Please note that the above configurations cannot be combined, which means
+maximum number of TRX one can achieve is 2 by using separate physical RF
+channels, or 3 by using multi-ARFCN method. You cannot support, for example, 6
+ARFCN operation on B210 using 3 TRX on side A and another 3 TRX on side B.
+=== LimeSDR-USB
+The binary _osmo-trx-lms_ is used to drive this device, see <<backend_lms>>.
+This device comes with 2 RF channels, so it should theoretically be possible to
+run a multi-TRX setup with it, but there are yet no records that this kind of
+setup was tested with this device.
+This device has 3 different Rx paths with different antenna connectors in the
+PCB, each with a different frequency and bandwidth range. One should make sure
+the physical antenna is connected to the correct connector matching the Rx path
+you want to use. If one wants to be able to use the device in both 900 and 1800
+MHz GSM bands and easily switch between them, then Rx Path `LNAW` should be used
+,since it is the only one covering both bands, and the antenna physically plugged
+accordingly. Following example shows how to then configure _osmo-trx-lms_ to use
+that Rx path to read samples.
+.Example: Configure osmo-trx-lms to use LNAW as Rx path and BAND1 as Tx Path
+ ...
+ chan 0
+ tx-path BAND1
+ rx-path LNAW
+=== LimeSDR-mini
+The binary _osmo-trx-lms_ is used to drive this device, see <<backend_lms>>.
+As a smaller brother of the [[dev_limesdr_usb]], this device comes only with 1
+RF channel. As a result, it can only hold 1 TRX as of today.