DIY Cellphone
web.media.mit.edu
web.media.mit.edu
This is fantastic, and I'm excited to see what more David will be working on in the future; his dissertation will be an interesting one :)
I've seen a few DIY projects here and there involving GSM, but his name is what really caught my eye in the first place.
You may also find these interesting:
http://www.open-electronics.org/gsm-gps-shield-for-arduino/
http://www.instructables.com/id/ArduinoPhone/
I'm sure there's room to mix and match improvements.
No, none of this is very interesting at all until there is an open, free baseband firmware.
I don't think most people will find this helpful though. One of the main problems is that the chip vendors don't tend to release the hardware specifications and development tools.
Several of the USA carriers are itching to phase out all their 2G networks, so that they can re-use that spectrum for LTE. So a 2G baseband has limited usefulness moving forward.
Adding to that, implementing any kind of 3G (WCDMA, HSPA) is an order of magnitude more complex. Just the handoffs between a 2G and 3G cell tower are complex.
Sadly, LTE is sort of simpler than the 3G technologies, because its all just data (no special transfer mode just for voice). However, instead just going all IP protocols for voice and other services, they decided to implement a host of new and complex protocols for Voice-over-LTE (VoLTE). And some of the current chipsets now have to handle handoffs between LTE, 3G and 2G.
So this open-source stack will not get carrier approval. And even if it were to get popular, the FCC would likely throw up a stink, and the carriers would start banning users that are using a non-approved 2G stack. They would be somewhat justified in that because the existing baseband implementations go through extensive (and expensive) compatibility testing to make sure they place nice with the network under all possible conditions.
If you want to do open-source radio, your first fight is to get some spectrum that can be used unlicensed. There's big competition for the best frequencies (that can carry enough data and have decent range), so the spectrum auctions cost billions of dollars, and the winners are the existing major players.
Yes they can snoop on the users, but they can do that now, without any changes to the radio firmware on the phone. The modem can't really do anything without the carrier's network.
If you mean spying on users by surreptitiously turning on the microphone, that's something where you want to control the phone's application processor rather than the modem firmware. Mostly because modern phone architectures have the microphones connected to the app processor instead of directly to the modem as in the feature-phone days (like a few years ago). Modern phones have sophisticated echo and noise reduction and use multiple microphones for that. And the audio is now used for other applications (like Skype or video recording) so it makes sense to hook up the microphones to the app processor instead.
But this is a much more advanced project - you need to supply your own box to put it in too ..
The day will come when we will all hold cell phone shaped PCs. You'll be able to interact with them as you do now. However, when placed within 10 feet of a keyboard or mouse, they'll automatically (configurable) and wirelessly use those peripherals ... keyboard and monitors on the fly baby!
Imagine optional super thin foldable displays to pack in the bag ... keyboards too ... or, go big and use production color accurate displays like my NEC 2490WUXi2. Thus making our own like this seems appropriate.
Re the actual article - very interesting. Wish I knew how to solder. Reminds me of the ancient days when people bought their computers as kits.
I might like to have some kind of charging pad that does it, you just take your phone out and toss it on the pad and there you are. Have it be 'automatic' only while in contact with a specific surface.
Let's think about this... A keyboard is basically a device for entering text via mechanical (or touch) switches which appear on your console/screen. A mouse is a virtual index finger.
Even though most of us can't imagine our daily lives without them at the moment, they both seem archaic in a way. Don't get me wrong; I think that's part of their appeal (I have an IBM model M somewhere in storage), but their high-tech-ness(?) is a bit of a non-sequitur when the day comes when our phone/device/gadget/pc-thing can talk effortlessly to a keyboard and mouse.
It's almost as if a mirror with built in camera interfacing to your straight razor. Some things are best left old-fashioned.
Even in a future in which spoken commands become commonplace, using a keyboard and mouse has an advantage. After all, I don't necessarily want everyone to hear every word I speak into a textbox.
It's like the similar argument about digital books replacing print books. Even though printed material technically (depending on if your definition of 'printed' includes cuneiform) has been around since Babylon. Its being old is no reason necessarily to replace a peripheral, so long as its function is still adequate.
Project the display onto a wall and project the keyboard onto the desk, the unit would detect the position of your fingers over the keys using similar techniques to how Kinect works.
A while ago I had a cell phone where the battery charging circuitry went out. The battery was 3.6v, so I hooked up (via Velcro) a AAA battery holder and used rechargable NiMH batteries. However I was told (when I called the airline I was traveling) that it most likely wouldn't make it past TSA.
Forgiveness Procurement difficulty: Low. Likelihood of successs: High.