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Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

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Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#12
post #11
post #4

That’s… odd? I would’ve assumed that LE was designed with both theory and practical testing - how could classic be better at everything?

Maybe classic is engineer's creature while LE is manager's one?

For the most part, Classic was designed by committee with many concessions to every corporate partner, retaining compatibility with their IrDA stacks, etc...

...while LE was designed by a few smart guys working together

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#13
On this topic: I'm very interested in streaming accelerometer data in real time from a wrist worn device to a body mounted LED controller. My goal is to modify the LEDs animations based on the hand position. Given the sensor bitrate and low latency required for this data, it would appears that BT Classic may be better solution than BLE. Beyond the power consumption needs, BLE connectionless broadcasting of the data seems easier to handle with than having to manage pairing two device. You could simply pick the strongest signal and be reasonable assured that it's your personally worn wrist device.

Am I missing something?

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#14
post #4

That’s… odd? I would’ve assumed that LE was designed with both theory and practical testing - how could classic be better at everything?

Classic isn't better at everything. This was just looking at the raw efficiency of sending as much data as fast as possible from device to device, something both classic and LE bluetooth can do. However classic cannot do quite a bit of what LE supports, for instance things like wireless multicast (i.e. air tag type scenarios) where one device broadcasts data for any other device around it. Classic is much more like a wireless serial port and requires devices to find and connect to it one at a time whereas LE doesn't have that strict requirement.

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#15
post #13

On this topic: I'm very interested in streaming accelerometer data in real time from a wrist worn device to a body mounted LED controller. My goal is to modify the LEDs animations based on the hand position. Given the sensor bitrate and low latency required for this data, it would appears that BT Classic may be better solution than BLE. Beyond the power consumption needs, BLE connectionless broadcasting of the data s…

> You could simply pick the strongest signal and be reasonable assured that it's your personally worn wrist device.

> Am I missing something?

Phone is in your pocket, wrist worn device is on other side of your body. Another device with unobstructed line of sight across the room may have a stronger signal strength.

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#16
post #13

On this topic: I'm very interested in streaming accelerometer data in real time from a wrist worn device to a body mounted LED controller. My goal is to modify the LEDs animations based on the hand position. Given the sensor bitrate and low latency required for this data, it would appears that BT Classic may be better solution than BLE. Beyond the power consumption needs, BLE connectionless broadcasting of the data s…

Where are you planning to use this, is it for a stage or concert? A lot of folks have found in those environments 2.4 ghz wireless (like bluetooth) is flakey and unreliable from all the interference of the audience's devices. I've read folks prefer stuff like 900mhz where almost no one has stuff using it in the area. Akiba and Freaklabs has done some great write-ups about his stage show work that are worth exploring: https://hackaday.com/2013/12/10/get-tangled-up-in-el-wire-wi...

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#18
The "LE" is more about behavior, rather than some power-saving tech. It affords low-energy-use behavior. Short bursts, ad hoc connections, small amounts of data, etc. If we make it behave like Classic, it will suck energy like Classic.

I like using BLE, more than Classic (BR/EDR). It's a bit pedantic, getting things set up, but that can be abstracted, fairly easily[0].

If we program for iOS/WatchOS/TVOS/iPadOS, we'll generally be using LE, as Core Bluetooth is designed around LE. Classic is there, but IOBluetooth is only meant for MacOS, and is a private API, on the other platforms.

LE is basically meant for short busts of control information, or small bits of data. Its encryption is pretty good. You can actually have a meaningful dialogue, just using the advertising information, so a connection is not always required (beacons use this).

I have heard that they will be adding some high data-rate stuff to LE, so we may be seeing true LE headphones, in the future.

[0] https://github.com/RiftValleySoftware/RVS_BlueThoth

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#19

What's going to matter for audio streaming in an automotive (the case they are concerned about) is the energy consumption in the receiver, not the transmitter. They are measuring the second.

This is killing my in my newest stereo, the bluetooth will sleep if the phone is silent for more than 1 second, like a breathy pause during a audiobook. Then it takes a half second to kick back in. I haven't found anyone with a solution yet.

Re: Analysis of energy consumption of Bluetooth Low Energy versus Bluetooth Classic

#20

What's going to matter for audio streaming in an automotive (the case they are concerned about) is the energy consumption in the receiver, not the transmitter. They are measuring the second.

Who cares about power usage of the receiver in a car? It's got access to the 12v alternator/battery and as long as it turns off properly hen the car is off, radio power is going to be negligible compared to moving the vehicle, nevermind things like air conditioning, power steering, headlights, etc.

Otoh, the transmitter in your pocket might not be plugged in, so that's important.

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