# What is the smallest component to send HTTP requests on the Internet? [closed]

I want to build a GPS tracker to put on my bike and I would like to use the smallest components to do it. The idea is to send the GPS coordinates to an HTTP server every minutes.

The problem is all the components I found for GSM or 3/4G are all too big (around 50x50 mm).

Does it exist smallest components? Or does it exist alternatives to send data to a server?

• Let's take a look at everything you need: A GSM antenna, GSM chip, the power management for such (as sending/receiving cellular data is power hungry), a GPS, GPS antenna, and a microcontroller to coordinate it all. Don't forget the battery. It seems that a 50mmx50mm solution for all of that (minus the battery I'm guessing) seems pretty remarkable, considering 50mm is about 2", so you are talking about a 4 square inch board. – Ron Beyer Dec 28 '19 at 16:42
• @RonBeyer 50mm x 50mm is what I found only for the GSM chip. I didn't take into account the other components. Indeed, if the final result can have this size, it can be ok. Let's say, if it fits and can be hide on a regular bike, it's perfect. – Pierre Dec 28 '19 at 16:45
• Any "correct" answers will be out of date in a month hence voting to close. – Andy aka Dec 28 '19 at 17:50

Since product recommendation questions are off-topic, I'll answer the underlying question of

How small could a fully functional 2G/3G/4G module possibly become?

The answer to that lies in physics:

The wavelengths involved in these microwave cellular standards are in the range of 10 to 30 cm.

Efficient antennas are typically in the order of ¼ of the wavelength, but using very narrowband designs, or very high $$\\varepsilon\$$ chip antennas, you can maybe shrink them down to a couple of centimeters.

Below that, you simply can no longer efficiently capture (or emit) radio wave energy, and thus, can't communicate with the network.

So, antennas set a natural lower boundary for what is possible, size-wise.

You could of course try to move the antenna off-board (which might be very wise, if you plan to mount things e.g. in a pipe), but vibration-safe RF connectors are way more complex, expensive, and possibly not even significantly smaller than antennas.