Summer 2007 Vol. 16 No. 2   


Transceiver with Dual Wideband DDC and Interpolation Filter - PMC/XMC

7140-420 Installed Core


  • Complete software radio transceiver solution
  • Installed Core 420 dual high-performance wideband DDCs and interpolation filter installed
  • Improved dynamic range
  • Extended DDC decimation range of 8 to 1,048,576
  • Extended DDC bandwidth range of 10 MHz to 76.3 Hz
  • Extended DUC interpolation range of 2 to 16,384
  • Extended DUC bandwidth range of 40 MHz to 4.88 kHz

Model 7140-420 Transceiver

General Information

Model 7140-420, Dual Digital Transceiver with Wideband DDC and Interpolation Filter cores, is a complete software radio system in PMC/XMC format. It includes two A/D and two D/A converters for connecting to HF or IF ports of a communications or radar system.

The 7140 receiver section features two AD6645 105 MHz 14-bit A/D converters and one TI GC4016 quad multiband digital downconverter. The digital outputs of the A/Ds are delivered to the Virtex-II Pro FPGAs and to other module resources including the GC4016 which supports a decimation range from 32 to 16,384. For an A/D sample clock frequency of 100 MHz, the output bandwidth for each of the four channels ranges from 2.5 MHz down to 5 kHz. By combining two or four channels, decimations of 16 or 8 can be achieved for an output bandwidth of up to 5 or 10 MHz, respectively.

For applications that require even wider bandwidths, Pentek offers the IP Core high-performance Wideband DDC and an interpolation filter that extends the range of the DAC5686 D/A converter.

Core 420 Wideband DDC

The Core 420 downconverter translates any frequency band within the input bandwidth range down to zero frequency. A complex FIR low pass filter then removes any out of band frequency components. An output decimator and formatter deliver output data in either real or complex representation.

Two identical Core 420 DDCs are factory installed in the 7140 FPGA. The decimation range from 2 to 64 in six binary steps provides output bandwidths from 40 MHz down to 1.25 MHz for an A/D sampling rate of 100 MHz. It also delivers better stopband rejection than the GC4016 in combined channel modes.

A multiplexer in front of the Core 420 DDCs allows data to be sourced from either the A/D converters or from the output of the GC4016, extending the maximum cascaded decimation factor to 1,048,576.

Core 420 Interpolation Filter

The interpolation filter included in the 420 Core, expands the interpolation factor from 2 to 16,384 programmable in steps of 2, and relieves the host processor from performing upsampling tasks. Including the DUC, the maximum interpolation factor is 16,384 which matches the maximum decimation of the GC4016 narrowband DDC.

Core 420 is also available for cPCI Model 7240, Model 7340 and PCI Model 7640.

Conduction-cooled version is availalable with Model 7141-703.

For more information and a price quotation on the 7140-420, click here.