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Comment by lovelearning | Hacker News Reader

I couldn't spot the typical wavy PCB antenna pattern anywhere. Is that small cube in the upper left corner of external top view a ceramic antenna? Looks to me like the 2 LEDs have been shifted further down towards lower left and replaced with something new.

Update: Just noticed the radio testing report says single PCB mounted chip ceramic. I still can't spot it with certainty.

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Yes, this is the antenna.

I cant believe it took them that long, Broadcom is famous for their BT/Wifi chips, buildin wifi was a no brainer, and cost shouldnt be an issue when you have great connections inside the company.

From their blog posts and forum discussions, I have the impression BC was not exactly enthusiastic about the Pi to start with, but got convinced only after Pi v1 become a hit. Perhaps there is still some reluctance and resistance inside BC? After all, they did take ~3 years to upgrade from ARMv6 to ARMv7 while all the other SBCs were already using ARMv7 cores much earlier.

Are you sure that's the antenna? It looks more like it'd be a balun. It even has what looks like a feed line going to the keepout that's right next to it. I feel like the one in the picture is missing the actual antenna.

balun (white ceramic part with brown rectangle marking) appears to be on the other side between the chip and via to the antenna

http://www.digikey.com/catalog/en/partgroup/2-45ghz-balun/52... or similar

Oh, it's on top (which they totally said). I'm not a smart man.

Is a ceramic wifi antenna's range comparable to that of a regular PCB antenna?

Usually slightly better, as it can be a 3D structure.

More accurately, better if considering antennas of equal footprint area, however chip antennas are usually designed to be very small (like this one) as the extra cost is only justified when space is at a premium.

In my experience in practice a good-sized PCB antenna beats tiny ceramic antennas. I would expect the radio performance of this Pi to be pretty poor, though better than using one of those tiny USB adapters (which also typically use even smaller ceramic antennas with really awful ground reference when used in a Pi as they are designed for use with laptops).

Also, another reason for their smaller size is that ceramics can have very high dielectric constant which reduces the size of the antenna.

It looks like the ceramic antenna is the light brown SMT between the DSi connector and the upper left hole in the top view pictures.

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