Software Radio PMC Packs Power Meters And Beamforming Capabilities

The Model 7152, a quad, 200-MHz 16-bit a/d digitizer with a 32-channel digital down converter (DDC) in a PMC format, includes power meters with threshold detectors and beamforming capabilities. It comes with pre-installed DDC IP cores for Xilinx FPGAs and employs proprietary signal-processing techniques to enable a 200-MHz sampling rate. The PMC features 32 power meters that continuously measure the average power output of each DDC channel. The time constant of the averaging interval for each meter is programmable for up to 16 ksamples. The 32 threshold detectors automatically send an interrupt to the processor if the average power level of any DDC falls below or exceeds a programmable threshold. Both the power meters and threshold detectors offload these tasks from a downstream processor and present average power measurements for each channel in easy-to-read registers. A second set of features makes the module ideal for beamforming applications. Each DDC channel offers programmable gain and phase adjustments, applicable individually or synchronously to all channels. A summation block adds the outputs of selected DDC channels. By adjusting the phase offset and weighting of the individual channels, followed by summation, the antenna can be steered, rotating the azimuth angle to enhance reception in a particular direction. Price for the 7152 PMC module (hardware) is $14,500. PENTEK INC., Upper Saddle River, NJ. (201) 818-5900.