How do Airport body scanners work? Explained!


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Hey friends, Happy Wednesday!

Last Saturday, I attended my friend’s housewarming function and played Codenames with a couple of my friends.

Let’s look at how Airport body scanning technology works this week. It is also called Millimeter wave detection and I noticed the name for the first time when I was traveling to Los Angeles last time. Looking back, I feel like writing a newsletter on technology helps a lot as I subconsciously keep looking for gadgets to write about and keep wondering how they could possibly work :)

I aim to write my newsletter issues in a way one can follow them while traveling on a bus, having a coffee, waiting for your food, etc. Let's jump in!

Tweet of the week

I’m sharing a cool fact about gadgets every day on Twitter. And here is one of them for you.

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Chendur Singaram
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@ChendurSingaram
May 21st 2023
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How does Airport body scanning technology work?

Introduction

Millimeter wave detection is a technology used in airports for security screening purposes. It enables the detection of concealed objects or threats on a person’s body without requiring physical contact or the need to remove clothing.

How do Millimeter wave scanners work?

  1. Millimeter waves are electromagnetic waves with frequencies ranging from 30 to 300 gigahertz (GHz). These waves have short wavelengths, typically between 1 and 10 millimeters, hence the name “millimeter wave.” They have the same speed as light but are not visible to the naked eye.
  2. The scanning device uses small transmitter discs stacked on one another like vertebrae in a spine to produce waves. They are stacked vertically so as to scan you from head to toe. The scanner has two stacks on the opposite ends of a machine, protected by a curved shell called a radome. The transmitter emits low-power millimeter waves that pass through a person’s clothes.
  3. If a person is concealing any objects under their clothing, such as weapons, explosives, or other prohibited items, these objects can cause disruptions in the millimeter waves’ transmission and scattering patterns. They are scattered or diffracted.
  4. The same transmitter now acts as a receiver and detects the returning signal. The distance is calculated by measuring the time it takes for waves to travel to an object and back. By timing this round-trip, the scanner determines the distance.
  5. This information helps create a detailed representation of the object or person being scanned. By rotating the stacks around the person, the scanner creates a full picture of the person’s body, capturing details from head to toe and front to back.
  6. Trained security personnel review the generated images to identify any irregularities or anomalies that may indicate the presence of concealed objects. And, this is how airport body scanners work!

Task of the week

The next time you take a flight, let me know if you noticed this amazing technology. Did your experience change this time? The reason I ask this is because, whenever I understand how a gadget works, the way I see it the next time changes completely! Looking forward to hearing from you.

Blog posts

My blog post-S2E8 and S2E9 exploring how Wireless Charging and GPS works is coming out next week!

I’m including an extended summary of how a gadget works in my newsletter, from which you can understand the essence in less than 3 minutes. But you can choose to read the blog posts for a more detailed version involving the nuances, from the links I attach.

Gadget of the week

Security: The Moorebot Scout is a cool robot that monitors your home while you're away. It connects to WiFi and works with a phone app, Google Home, and Alexa. It can be an RC vehicle or patrol on its own using AI. It charges itself by docking and moves in all directions. With facial recognition, it identifies who's in your home or office. It sends immediate notifications if it spots something suspicious.

Thank you for reading!

Have a nice rest of the week, and take care!
Until next Wednesday,
Chendur

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How Do Gadgets Work?

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