National Instruments Cabled PCI Express manual Relevant NI Products and Whitepapers, Software

Cabled PCI Express as a Standard Interface for Virtual and Synthetic Instruments

The focus of the SIWG has been primarily on the SI concepts as applied to RF stimulus and measurement systems. Data intensive applications, like RF testing, require a high-bandwidth, low-latency bus to connect the IF digitizers to the processor (see Figure 5).

Figure 5. Synthetic Instrument RF Block Diagram

For example, to digitize a 50 MHz wide RF signal requires 100 Mbytes/s of bandwidth (at 2 bytes of resolution per sample). For an input and output channel, this grows to 200 MB/s. And for increasingly common multi-channel, or MIMO (Multi Input, Multi Output) applications, the bandwidth required can quickly scale to multiply gigabytes per second. PCI Express, and cabled PCI Express in particular, is a leading contender for this high speed link because of its excellent technical capabilities, wide commercial adoption, and low-cost infrastructure.

Cabled PCI Express is based on PCI Express and so provides a scalable, high-bandwidth, low-latency bus for chip-to-chip, board-to-board, and box-to-box applications. In the past some data intensive applications couldn’t transfer the data fast enough to the host PC and so the data was processed in the box instrument using vendor-defined software and hardware. Cabled PCI Express opens up a new larger and faster pipe to the host PC so more applications can take advantage of user-defined software and hardware for measurement processing and analysis. Today NI uses cabled PCI Express to connect host PCs to PXI chassis with MXI Express. It currently sustains transfer rates of 110 MB/s for a x1 link and 798 MB/s for a x4 link. In the future, cabled PCI Express may offer a compelling bus solution for synthetic instrumentation.

Relevant NI Products and Whitepapers

National Instruments, a leader in automated test, is committed to providing the hardware and software products engineers need to create these next generation test systems.

Software:

•NI TestStand Test Management Framework

•LabVIEW Graphical Programming Environment

•Signal Express Interactive Measurement Software Hardware:

•Modular Instruments (Oscilloscopes, Multimeters, RF, Switching, and more)

•Multi-function Data Acquisition

•PXI System Components (Chassis and Controllers)

•Instrument Control (GPIB, USB, and LAN)

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