USRP-2945/2955 are using the TwinRX daughterboard. The TwinRX daughterboard for the USRP X Series SDR platform is a two-channel superheterodyne receiver designed for high performance spectrum monitoring and direction finding applications. Because of the feature of superheterodyne frontends, it uses two IF to donconvert an RF signal to baseband signal in each channel as is shown in specification.
The LO specification of USRP-2955
According to TwinRX IF Board Revision C
, it delivers input RF signal to lowband and highband and it use ADF5355
as LO1 and ADF4351
| ||Highband (1.8GHz - 6.0GHz)||Lowband (10MHz - 1.8GHz)|
|IF1||1.25GHz +/- 40MHz||2.345GHz +/- 40MHz|