microwave calculators noise figure

microwave RF information for engineers encyclopedia calculators tools

skin depth cpw calculator pin diode

directional coupler smith chart microwave dictionary

December 12, 2017
phased array frequency meter

microwave jobs career recruiting antennas twitter

bandwidth microwave measurements

noise figure phase shifter microwave encyclopedia

s parameters waveguide variable attenuator acronyms

internet of things ios attenuator calculator

× This discussion topic is moderated by MTT-S Technical Committee #11

Terahertz scanner: does it work?

More
6 months 3 weeks ago #826 by Averichev
Averichev created the topic: Terahertz scanner: does it work?
Hello everyone,

Maybe someone good at this topic or met this problem before, because I was really confused reading about this
www.tera-sense.com
Can someone tell me: does it actually work? And how terahertz radiation can influence on the human body, considering that THz waves passing through variety of things, such as plastics, ceramics, composites etc.? Thanks in advance!

Please Log in or Create an account to join the conversation.

More
6 months 3 weeks ago #827 by Dave
Dave replied the topic: Terahertz scanner: does it work?
THz imaging works. If I'm not mistaken, the full body scanners in airport security lines are THz systems.

There are two main areas that I know of: active and passive. As the name suggests, active requires a source to illuminate the target. A little more complicated, but you get better dynamic range as a result.

I'm by no means an expert, but as far as I know, THz imaging is human safe, unlike X-rays. The THz waves only penetrate a very short distance into the skin, whereas X-rays pass right through. There's a lot of research going on in the use of THz imaging for medical purposes to sense skin problems and the like.

Maybe someone going to IMS could hit them up for more info about how it works.

Steve, what about talking them into sponsoring some microwaves101 content on THz imaging?

Please Log in or Create an account to join the conversation.

More
6 months 1 week ago #828 by Microwaves101
Microwaves101 replied the topic: Terahertz scanner: does it work?
I agree that T-waves are not going to harm you. Active is much faster than passive to form an image, therefore that is what is used by TSA.

Who should we hit up about describing airport scanners? Know anyone at L3? I will try to track down some medical researchers at IMS, good idea.
The real controversy about airport scanners is that they see every detail of your nude body. This became big news in 2010, shortly afterward, scanner designers made the cartoon interface for the airport personnel to look at.

www.dailysquib.co.uk/most-popular/2389-b...olorado-airport.html

Steve

Please Log in or Create an account to join the conversation.

More
6 months 1 week ago #831 by Dave
Dave replied the topic: Terahertz scanner: does it work?
I don't know anyone in that part of L3, but it looks like they're the market leaders for THz scanners, so should have some good material to draw on.

If not this year, next year's IMS has certainly got a strong bio-med theme, which I'd hope would draw plenty of researchers in that field.

Please Log in or Create an account to join the conversation.

More
6 months 1 week ago #832 by Dylan
Dylan replied the topic: Terahertz scanner: does it work?
Dear Dave,

I believe that the TSA airport scanners use millimeter waves. These penetrate clothing easily. THz waves also penetrate clothing reasonably well, and give you better resolution as the wavelength is smaller. But the exact choice of frequency at THz frequencies is important, and anything above 300 GHz is often called THz.

Best,

Dylan

Please Log in or Create an account to join the conversation.

More
6 months 1 week ago #833 by MMWENGR
MMWENGR replied the topic: Terahertz scanner: does it work?
I can confirm from first-hand knowledge that the Provision airport scanner is millimeter-wave. Clothing penetration is important to detect contraband, but resolution is more a function of the bandwidth of the waveform; the wider the bandwidth the better the resolution. Modern scanners utilized in airports utilize software "masking" to detect contraband without revealing body details. This has been true for years. Most of the systems I am aware of utilize a FMCW waveform to achieve wide bandwidth and better resolution. PNNL (Pacific Northwest Labs) is where a lot of fundamental research on security scanners has been and is being done.

Dave

Please Log in or Create an account to join the conversation.

Time to create page: 0.073 seconds
mobile app designers california