Social Feed

A cell phone needs an antenna. It generally needs a bunch of them, really. There's one for the traditional cellular frequencies, one for mid-band, one for ultra-wide-band, one for Bluetooth, and at least one for Wi-Fi. So where are they?

First a little bit of physics (don't worry)

Everything that receives or transmits needs an antenna. That's just the way it works. The antenna needs to be a particular size, and that size depends on the frequencies being used. The higher the frequency, the more you can kind of "fudge" that size issue and use one antenna that kind of gets a bunch of frequencies.

All cell phone frequencies use the UHF band or a band even higher than that. Cell phones can use frequencies from 600-2150MHz, as well as 3300-3800MHz and a large range up around 30,000MHz as well. Bluetooth and Wi-Fi add the need to communicate at 2400MHz and 5800MHz. That's a lot of different tech to consolidate in something as small as a cell phone. So, finding placement for an antenna can be a challenge, especially since no one actually wants to see the antenna like they did on the old flip phone above.

A lot of stuff is on the side

UnitedLex.com

Since about 2010, a lot of phone manufacturers have been putting antennas on the side of the phone. The sides of the phone can be metal and by using small plastic gaps, they can create antennas that are the right size. That's what you see above. Apple started doing this with their iPhone 4, although they realized fairly early that they weren't doing it well. Early phones with side-mounted antennas could stop working if you shorted the antennas with your hand, which pretty much happened whenever you held one. Newer phones use non-conductive coatings and other tricks to make sure you can, yknow, actually hold your phone while you're using it.

Stuff can be on the back or inside as well

The image above also shows a small black window on the side. On this phone, that window was used to give access to the 5G antennas on the inside. Making the back of the phone out of glass or plastic makes it easier to put antennas where you need them. Those materials allow signals to pass through easily. Early smartphones had metal backs with a large plastic window, as you can see from this image of the original iPhone.



Putting those antennas on the back of the phone means that they can be the size and shape that they need to be and still work well. It also means there won't be interference from the display itself. Wi-Fi and Bluetooth antennas can be really small and still work well, although obviously bigger antennas would work even better. The thing is no one wants a phone that looks like a gaming router!

Antennas sure are an art

I think it's amazing how these designers find a way for every antenna and every chip they need in such a small package. When you consider that most of the space on a phone is reserved for a battery, it's even more amazing. Take out the battery and the display and you're left with a board about the size of your pinky and a few other daughterboards that mostly handle things like buttons, ports, and connectors. I'm glad I don't have to be the one to think about how to package all that stuff up. Although, I'll admit to some interest in watching teardown videos, especially the ones that don't actually destroy the phone as they are tearing it down.

Need a new phone? Need better cell service?

You can get that new phone for home or business by calling Signal Connect at 888-233-7563. You can also get cell phone signal boosters that make your phone work better inside. Even with today's great cell networks, almost everyone experiences poor cell service at some point in the day. Don't get disconnected! Let us help. We're here during East Coast business hours. If it's after hours, no problem! Fill out the form below and we'll get right back to you.


The post Where is the antenna on your phone anyway? appeared first on The Solid Signal Blog.

Continue reading...