THz Imaging Arrays: Challenges and Opportunities

THz technology can loosely be defined as electrical, optical
components and systems that work in the 300-10000 GHz range. In
the last few years JPL has led the development of electronic sources
and detectors in this frequency range with enabling space instruments
to make unprecedented science measurements. Recently we have
extended this to demonstrate a source at 2.7 THz that puts out > 10
micro-watts of CW power at room temperature. We have also used THz
technology to develop FMCW radars that allow for remote "pat-downs"
working at 340 GHz and 670 GHz. THz images from a 340 GHz system
are shown below that can detect anomalies beneath winter jackets.
The radar is eventually limited by mechanical constraints which can
be overcome by using a multi-pixel receiver. Similarly for future space
instruments multi-pixel receivers can increase science throughput.
However, making heterodyne imaging arrays has a number of
challenges. This talk will present a novel approach being pursued in
our group that utilizes silicon micro-machine technology along with
advanced GaAs and CMOS chips to enable robust and compact array
receivers. The talk will focus on presenting some of the challenges and
opportunities in developing this technology.
Imran Mehdi (BSEE 1985, MSEE 1986 and Ph.D 1990, University
of Michigan) is a Senior Research Scientist at the Jet Propulsion
Laboratory, California Institute of Technology. He joined JPL in 1990
and is currently a Group Supervisor in the Instrument Electronics
and Sensors Section. His responsibilities include developing THz
components, technologies and subsystems for current and future
NASA missions. These devices and components were implemented on
several space instruments such as MLS, MIRO and HIFI. From 1999 he
led the effort of developing broadband solid-state sources from 200 to
2500 GHz for the Heterodyne Instrument for Far Infrared (HIFI) on the
Herschel Space Observatory, a cornerstone European Space Agency
mission. He is an IEEE Fellow and serves as a topical editor for the IEEE
Transactions on THz Science and Technology. His current interests
include millimeter and sub-millimeter-wave devices, high-frequency
instrumentation, and heterodyne receivers for miniature systems.