The NI 5793 is an RF transmitter with continuous frequency coverage from 200 MHz to 4.4 GHz, with 200 MHz of instantaneous bandwidth. It features a single-stage, direct conversion architecture that provides high bandwidth in the small form factor of an NI FlexRIO adapter module. The onboard synthesizer (local oscillator or LO) sets the center frequency for acquisition and generation, and can be exported to other modules for multiple input, multiple output (MIMO) synchronization. The LO can also be imported from an external connector, enabling synchronization of up to eight NI 5793 modules.
The baseband digital-to-analog converter (DAC) features 16-bit resolution and a 250 MS/s data rate, which simplifies algorithm design. In a digital signal processor (DSP) on the DAC hardware, the data is subsequently interpolated two times to 500 MS/s before generation, which reduces out-of-band images. Direct access to raw DAC data on the NI FlexRIO FPGA module provides the ultimate flexibility in digital signal processing, data storage and streaming, and custom algorithm design for software defined radio (SDR), signal intelligence (SIGINT), streaming to and from disk, MIMO, beamforming, and other high-performance embedded RF applications. Additionally, the NI FlexRIO FPGA module and the PXI platform offer a means for analog-to-digital converter (ADC) and DAC data synchronization, which is necessary for channel expansion. Twelve bidirectional digital I/O lines routed from the FPGA to a connector on the adapter module enable digital device under test (DUT) control and simple digital protocols. Though the NI 5793 is compatible with all NI PXIe-796xR FPGA modules for NI FlexRIO, National Instruments recommends the NI PXIe-7966R to fit all of the provided LabVIEW FPGA software for RF configuration and DSP correction, in addition to any user code and IP. Examples for the NI 5793 are configured and compiled for only the NI PXIe-7966R.
RF performance on the NI 5793 is also exceptional given its size. The LO phase noise is better than 94 dBc/Hz at 2.4 GHz and a 10 kHz offset. All specifications are typical, and some require FPGA-based correction algorithms, which are provided in the form of example code.