Interconnecting Multiple PXIe-5645 RF Channels (Homogeneous Channel Types)

One key aspect of this synchronization is sharing local oscillators (LO) to tune the RF channel. The PXIe-5645 allows for import and export of the individual LOs on each RF input and RF output channel. The following figure illustrates recommended cabling for interconnecting LOs between multiple modules. The connections shown are between channels of similar type (for example, RF input to RF input or RF output to RF output).

Interconnecting Receive and Transmit Channels

A more specific application may require the RF input and RF output channels to share an LO. The following figure illustrates how to share an LO between the RF input and RF output channels on a single module.

The following figure illustrates how to share an LO between the RF input and RF output channels on multiple modules.

Note The PXIe-5645 does not support synchronization using daisy-chained Reference Clocks, for example, REF OUT to REF IN. For multidevice synchronization, lock all modules to phase-aligned Reference Clocks.

Note The RF output channel expects a 3 dBm LO power level above 3.6 GHz, and the RF input channel expects a 0 dBm LO power level. This expectation can affect performance for frequencies above 3.6 GHz and should be considered when implementing applications.