mmWave Imaging and Sensing

People passing through a walkthrough body scanner at an airport

From airports to shopping malls, there is a growing necessity for early, accurate, and fast threat detection. Millimeter wave (mmWave) imaging technology has evolved to deliver the necessary high detection accuracy without impacting traffic flow.

Traditional stand-still scanners are too cumbersome for venues with narrow entrances, too slow to process large numbers of people quickly, and too expensive to be practical for most venues. In contrast, a walkthrough scanner using mmWave sensing technology reveals concealed objects with high resolution detail—far superior to traditional walkthrough portals that simply beep if they detect something metallic. mmWave scanners show a security agent exactly where to look and what to look for should they need to inspect further, all in real time with high accuracy and speed.

The growing use cases for walkthrough systems go beyond airports and include stadiums, government security agencies, commercial, and municipal buildings.

Evolution Toward Walkthrough Imaging Solutions

Analog Devices’ industry-leading discrete RF ICs provide unparalleled performance in today’s systems. For the next generation of walkthrough threat detection, our mmWave imaging technology utilizes a new chipset to deliver faster, walkthrough solutions.

Chart showing the evolution of body scanning technology for threat detection
Body Scanning Evolution

What Should a Walkthrough mmWave Imaging Solution Deliver?

There are three main challenges in scaling mmWave body scanning technology for larger deployments at public and commercial venues.

Icon of a person walking quickly through a body scanner

Walkthrough Speed

 Icon of a threat warning symbol inside of a magnifying glass

Safety and Detection Accuracy

Icon of a double-sided wrench underneath a world globe

Ease of Deployment


Walkthrough

Stationary sensors enable multiple people to walk through at normal speed, instead of requiring each individual to pose and wait for processing by a moving sensor.


Safety and Detection Accuracy

mmWave imaging delivers accurate detection at tailored levels of sensitivity. While high resolution airport scanners need to detect small items, scanners in public venues only need to detect larger mass casualty items like firearms and explosives to deliver the required level of safety. This means fewer sensors can be used, which helps reduce cost and ease deployment challenges. It also means the system generates less data, which speeds up processing enough for people to walk through without stopping.


Ease of Deployment

To reduce both size and cost, multichannel RF ICs are needed to replace discrete signal channels. Because RF regulations vary from country to country, the sensing solution must be flexible enough to accommodate a range of frequencies and sensor positioning.

The Analog Devices mmWave Body Scanning Solution

Our imaging chipset for walkthrough body scanning delivers a scalable, high performance, highly integrated solution to move your design from development to prototype to high volume manufacture quickly and with reduced complexity.

Millimeter wave imaging systems operate by illuminating the target with low power RF signals and measuring the amplitude and phase of the reflected signal. Then, they build up a multilayer image that can see objects hidden between layers of clothing by sweeping the RF signals over a wide frequency range. Finally, they generate a detailed 3D image by sequentially illuminating the target from multiple spatially distributed sources—sometimes as many as hundreds of sources.

ADI’s mmWave chipset was created and optimized for use in walkthrough systems. Our chipset achieves:

  • Wide frequency range
  • Scalability for large arrays
  • Fast switching time
  • Low power consumption

Signal Chains

(1)

Click on a part in the diagram below

Key Products

3D image of ADAR2001 chip carrier

ADAR2001

4-channel 4× multiplier and transmitter that operates from 10 GHz to 40 GHz. An integrated state machine enables fast frequency sweeps, harmonic filter reconfiguration, and channel switching.

3D image of ADAR2004 chip carrier

ADAR2004

4-channel receive mixer with variable IF gain that also operates from 10 GHz to 40 GHz. The LO path includes a 4× multiplier and the device also contains a state machine to facilitate fast reconfiguration and switching.

3D image of AD9083 chip carrier

AD9083

16-channel, analog-to-digital converter with a JESD204B output interface. It was designed to seamlessly interface to the ADAR2004 and includes digital downconversion and the ability to simultaneously demodulate three signals on each channel.


For large arrays, ADI’s mmWave imaging chipset facilitates system scalability by enabling use of a single SPI channel to configure and sequence up to 64 channels without any hardwired address bit pins.

Are There Use Cases Outside of Threat Detection?

Walkthrough scanner detecting stolen IP on a man leaving a building

While threat detection is a leading use case, there are emerging applications in loss prevention at warehouses or buildings and in package verification during the delivery process. mmWave sensing technology can scan a person leaving a warehouse or other building to make sure they are not removing any objects. This could address loss of income from theft and even IP loss from a commercial or government building.