151–160 of 170 posts
2x the speed. 4x the range. 8x the capacity "to send messages" Not using the x.x versioning anymore. Just Bluetooth 5 and the next will be 6. Also, apprently, there's 30.000 companies in the 'Bluetooth Special Interests Group' ? [Thanks Krasin, gerardnll for correcting me]
Haven't look at the spec yet, but curious if they've improved the security side of communications. edit: Here's what I'm referring to, bluetooth 4 LE mode is vulnerable to certain attacks: https://lacklustre.net/bluetooth/Ryan_Bluetooth_Low_Energy_U... https://pomcor.com/2015/06/03/has-bluetooth-become-secure/
Earlier quoted context omitted.
The non-LE protocol has been pretty difficult to breach from the hacker-hobbyist level. The communication protocol is incredibly complex, and the hardware simply doesn't exist to interface well with it. A lot of BT2.0 (ie: non LE) "security" comes from the fact it's just darn hard to interface with it.
That sounds weird, given that it's in so many devices. It runs on a normal frequency and is implemented in billions of devices, how is it hard to interface with?
Earlier quoted context omitted.
"not even radio-compatible" Bluetooth 1.0 uses GFSK at 1 Msym/s, just like BLE / Bluetooth 4.0. So it's the same r/f modulation protocol (it's the higher layers that are incompatible.) Is it the actual GFSK parameters, eg. frequency shifts, that are different? I know that Bluetooth 2.0 and 3.0 use different r/f modulation (π/4-QPSK and 8DPSK at 1 Msym/s), but why do people say Bluetooth 4.0 is so different when it se…
One difference is that BLE uses 40 channels in its adaptive frequency hopping scheme, from Wikipedia: "Instead of the Classic Bluetooth 79 1-MHz channels, Bluetooth Smart has 40 2-MHz channels" Now that I write it out, I see that frequency hopping would count as a "higher layer," but I think it's still managed in hardware, which could be why there are many BLE-only chips. It's possible the GFSK parameters are also di…
Earlier quoted context omitted.
Getting 2.4GHz through the human body is hard. The human body is mostly water, and bluetooth is, after all, the same frequency of your microwave oven, which uses 2.4GHz because it's in a band of frequencies from 1-20GHz that water absorbs. When you're indoors, you don't need to get bluetooth through your body. You're getting reflections off of nearby walls and ceilings which allow your bluetooth devices to communicat…
Engineer's solution: drink less water when you want to use your wireless headphones (also, for a few days previous)
Earlier quoted context omitted.
As a user i kinda like the profiles, in particular the OBEX based ones. This because it means i can expect two devices to be able to share files out of the box if both of them have a bluetooth radio. Nothing like that exist for wifi, and i have to set up some client-server scheme to make anything happen.
The OBEX profiles predate even BT, they were inherited from IrDA. IrDA was an earlier method for transferring business cards or similar small files between hand held devices over an infra-red link link.
Earlier quoted context omitted.
You worked on BT specs ? BT seems an acute case of design by comittee. It's huge, full of profiles and corners. Nobody implements it really well, everything moves before it's finished. Makes you dream of wires some times.
I was involved in the 1.0 Bluetooth specifications and can confirm it was "designed by committee". IIRC the original wireless specification came from either Nokia or Ericsson and they drove a lot of the initial development. They had already developed the RF technology before the Bluetooth SIG was even formed. The original stated goal for Bluetooth was "cable replacement". Features such as pairing a headset to a phone…
Why is general bluetooth connectivity so "buggy"? Why am I always struggling connecting my iPhone 6s to my bose bluetooth speaker? I would love to understand that.
The only thing I've seen work reliably with Bluetooth, ever, is the PlayStation 4 controller. And only when pairing with the PS4 and not a PC. Sony seems to have gone out of their way to add some magical layer to establish and maintain those connections without the end user having to know or see anything about it.
Considering every phone I've tested (iPhone 5S, iPhone 6+, Samsung Note, Moto X, Nexus 6P) with 7 different bluetooth headphones (ranging from cheap Amazon ones to expensive LG) I have NEVER found a phone, paired with headphones, that stayed connected especially when the phone is in my side pocket and I'm walking in an open space which seems to make connectivity significantly worse. For instance getting on the BART b…
I wonder why 802.11ah isn't getting much industry love. It has a range of 1km! That's enough to cover an entire home and yard with "good enough" low-bandwidth coverage. Combine this with a mesh network and we could get very large private networks without many devices.