Dual Virtex-5s in a PMC transceiver

We’ve talked before about the growing high-end FPGA applications in military and aerospace platforms, and I couldn’t let the week slip by without mention of Pentek Inc.’s launch of a PMC transceiver module, the 400-MHz 7156, with dual Xilinx Virtex-5 FPGAs. This is a case of the FPGA being used to handle signal-processing algorithms that might previously have been handled by a DSP. But Texas Instruments Inc. need not worry, its monolithic data conversion devices, ADS5474 and DAC5688, were used in the transceiver alongside the Xilinx FPGAs.

Pentek anticipates the multichannel synchronization capabilities of the transceiver to be attractive outside traditional military radio applications, such as in wideband radar. By synchronizing multiple 7156 modules, a special front-panel digital connector allows the transceiver to be used in beamforming and phased-array duties.

The 7156 supports the VITA-42 XMC standard for switching fabric interfaces. The front-panel SMC connectors accept two analog HF or IF inputs at +8 dMb into 50 ohms, sending them into the TI ADS5474 14-bit A/D converters. The digital outputs are then sent into the dual Virtex-5 FPGAs for signal processing and/or routing.

TI’s DAC5688 accepts a baseband real or complex data stream from the FPGA, then sends that input to stages for upconversion and interpolation. A digital signal can be translated into an IF frequency of up to 300 MHz, then translated to an analog IF output via the DAC.

The module supports XMC and PCI-X, and allows customers to use Xilinx’s Aurora protocol for high-speed serial links, or Internet-Protocol-based links for use in IP environments. Pentek offers the same functionality in PCI, PCI Express, and Compact PCI in 3U and 6U formats.

The lesson here is not that FPGAs will supplant DSPs in high-end avionics, ELINT, and SIGINT applications, but that coexistence of high-end DSP and FPGA architectures will allow impressive baseband capabilities in small form factors.