DARPA chips in on Terahertz research
Solid-state receiver hits 850 GHz
The next frontier for solid-state electronics, the Terahertz boundary, has come a little closer with DARPA announcing a receiver operating at 850 GHz.
Currently, receiving and decoding THz signals requires a frequency down-conversion on the way, because nobody’s produced chips that can operate at such high frequencies. Down-conversion, however, limits the operating power of the receiver, and sets an unwanted floor under its signal-to-noise ratio – and adds to the footprint of the receiver.
In this  announcement, DARPA says it’s closing in on the THz range, producing a solid state receiver operating at 850 GHz (0.85 THz).
The agency says this development represents a step towards producing monolithic microwave ICs – MMICs to their friends – that can process the very high frequencies involved. It’s part of a two-part program, one focusing on transistors that can handle signal processing, the other developing the necessary power transistors.
DARPA’s own interest includes communications and its see-through-clouds VISAR (video synthetic aperture radar) program, designed to let fighters operate in conditions that currently inhibit current infrared sensors.
THz electronics are also useful for medical imaging (avoiding the side-effects associated with ionizing radiation – such as X-rays), and a range of industrial processes. ®