Dual Digital Transceiver Boasts A 4.8-kHz To 40-MHz Range

Comprising a complete software radio system in a PMC/XMC module, the Pentek Inc. Model 7140-420 dual digital transceiver with wideband digital downconverter (DDC) and interpolation filter handles input and output signal bandwidths from 4.8 kHz to 40 MHz. The module includes two analog-to-digital converters (ADCs) and two digital-to-analog converters (DACs) for connection to HF and IF ports. Suitable for a wide range of applications in signal intelligence, military and commercial communications systems, and radar, the module is available in a variety of form factors including PCI, 3U and 6U Compact PCI, and a PMC/XMC conduction-cooled version.

The GateFlow Core 420 includes a two-channel, wideband DDC IP-based core that complements the multiband Texas Instruments GC4016 ASIC. The DDC can be driven directly from the ADCs to achieve decimations from 2 to 64 for signal bandwidths up to 40 MHz. Alternatively, the DDC can be driven from the outputs of the GC4016 ASIC DDC using a cascade connection. This provides a maximum decimation of 1,048,576 to handle extremely low bandwidth signals down to 76 Hz. Thus, the GateFlow Core 420 DDC significantly extends both the upper and lower bandwidth limits of the GC4016 ASIC alone.

On the upconverter side, an IP core interpolation filter boosts the sampling rate of real or complex signals by a factor of 16 to 1024, programmable in steps of two. Acting as a pre-processing stage for the TI DAC5686 digital upconverter, the core extends the overall interpolation range for the module so it is programmable from 2 to 16,384. Consequently, with a 100-MHz output sample rate, the module now accepts baseband transmit signal bandwidths that can range from 40 MHz down to about 4.8 kHz.