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General discussion

bluetooth based applications

Jan 13, 2015 3:02AM PST

Hey guys, I was curious to know the battery consumption of bluetooth on a phone if I have it on all the time. Its for a project. essentially the connection will always be sending information to the phone, like 12+/- times a second? (something like that, could be more.....) I wanted to know, for on a regular phone like the Samsung Galaxy Nexus, how fast that battery life would be drained....

Discussion is locked

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Odd
Jan 13, 2015 3:12AM PST

Why not try it and see? This will be highly variable as phones bounce around on charge capacity even from one phone to the next or battery quality varies a lot too. Only folk new to this would think it would be repeatable from one phone to the next.

Which Galaxy Nexus model matters, what apps are installed and carrier configuration matters too.

Great question but it only serves as a launch point of what a mess you jumped into.

Bob (has written apps that use bluetooth)

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hmm
Jan 13, 2015 9:20PM PST

phones bounce around on charge? I dont understand....

What I want to know is....
how many piconets are capable of being within reach of each other without causing latency?
I know you can connect 7 to one master, and that 4.0 hops 1600 times a second, and that theres
40 channels but..... what does that mean in relation to how many can be within range without them
interfering with each other?

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The bounce
Jan 14, 2015 12:45AM PST

I should have written that you can pick up a dozen phones and get a dozen different results.

As to interference, what made you think that? You see 1000s of folk at CES that used WiFi. The packets fly in their time slots.

I'm left to guess you are researching (just starting out?) and not making, writing code, etc.
Bob

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so then....
Jan 14, 2015 2:13PM PST

thats so very true...... But I need there to be absolutely no latency between when the slaves sends the signal, to when the master device receives it........

does it help that I ONLY need the 7 slaves to transmit signals and not receive them? I need them to transmit signals CONSTANTLY, like whatever real time actually is....

so essentially; a bunch of Pico's around each other (talking about bluetooth) and around 160 master devices streaming a/v, and transmitting data all at one time, without latency..... **** I'm starting to hate that word lol....

I have been researching for a few years, 4 to be exact....
its for my project, which I can't really talk about, unless you think you can and actually want to help, but then I would need you to agree to my terms to not talk about it to anyone in a PM....

is hopping 1600 times a second a direct relation to how few collisions there will be?

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Then by design a failure.
Jan 14, 2015 2:57PM PST

There will always be some latency and lag. I've seen bad designs that don't put checksums and retries/handshakes into the comms and the company/designer buckles under the stress of the product failures.

I can help as I've written many apps that have used bluetooth over the years but what is this about those TERMS?

4 years? That's interesting. How did your prototypes work out? Hint? I've run into designers that never progress because that were in analysis paralysis.
Bob

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PM
Jan 16, 2015 9:25AM PST

I hope you received my PM?

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Not yet.
Jan 16, 2015 9:28AM PST

CNET's email services may be on leave.

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hmm...
Jan 18, 2015 1:02AM PST

do you have a personal Email? I will tell you the terms of my project if you would still like to continue talking about it, I'm looking for someone who can code in various languages and have deep knowledge of bluetooth and wifi.... We'll talk more in the email, but you must agree to my terms....

Just a heads up, I'm more a product manager than have any real knowledge on these systems.... of course I do my best to know as much about it all as I can but.... I don't know everything....

anyways...
too many wifi signals floating around would be troublesome... and pricey. I'm sticking to bluetooth because it's low power and from what I gather, a large group of signals can float around without interfering with each other. How many wifi signals would you say can bounce around without causing any delays? Are miniature versions of those 802.11 b/g/n dual routers available? probably not right......-sigh-.... damn it....

Interesting link you've provided thank you, I will look into it and mention you in my notes if I come across anything interesting. R Profit or bob would you like to go by?

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Sorry.
Jan 18, 2015 1:45AM PST

As long as the project demands zero delays (zero is zero) then I must bow out. I don't mind chatting about it but if a few milliseconds can't be allocated to package up the packet, transmit, and a retry well, that design must be one left for quantum communications that are yet to be fully developed.

I see your email and must wait for some non-zero spec. Maybe a newer designer would call 10 milliseconds zero but I can't.

-> Also, if you look at bluetooth PANs, there are time slots for transmission. If you want to send, you have to wait for your time slot. Another delay.

https://www.google.com/search?q=bluetooth+pan+timeslot+duration&ie=utf-8&oe=utf-8 finds a lot about this so again, zero is not possible.
Bob

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lol sorry
Jan 18, 2015 2:57AM PST

I didnt mean zero, I know zero is impossible....... For now >=] lol anyways....

Let me look into that, and I will tell you the actual number. I'm sure there is wiggle room, we should be fine.... I just wanted to know how much delay is caused by other pico's... Like I said I need 160 masters + 6 - 7 slaves floating around without too much present lag. Lets stay in the millisecond zone lol... In the rare case where there is continuous lag, I have a fail safe for that.... well, for several seconds (10?)

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Now we talking.
Jan 18, 2015 3:06AM PST
https://www.google.com/search?q=bluetooth+frequency+hopping&ie=utf-8&oe=utf-8 broaches why we can have many bluetooth things in the area. Between hops and time slots.

But all this doesn't matter.

Another project crashed as the principles discovered that users were not happy to turn on bluetooth and configure. Some of this we can automate on most platforms but here we are a dozen posts later and finally a move away from zero lag.

I find that the nuts and bolts rarely make or break an app or system. It's usually something simpler like a bad design out of the gate or a bad user interface.

This many posts and still no closer to what this is.

My background includes work on 2 way cellular texts in the 90's, industrial wireless data collection, apps on PalmOS, embedded, WinMo, Windows and hardware design.

Why not share if this is a game or data collection? Why get hung up on networking?
Bob
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hmm....
Jan 18, 2015 4:25AM PST

well, going back to what you said, this is one of those things that will break this if it doesn't work. As for the interface, I sorta got a plan for that too.

I will PM you.

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hmm...
Jan 16, 2015 9:43AM PST

well, when I talk about latency, I mean that up to 7 devices need to connect to one device at up to 60 times in a second, or whatever real time is.... without latency. Those people at those cons experience delays. I need none at all =/ I can reduce the Picos to 7 if I have to, or hows 15 sound? but no less.....ideally I would prefer 160.... sound crazy?... and no I don't have true experience with the finer terms and math and science behind my device, but.... I guess you could call me the producer of this project.... I know a little of alot......

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I'm sorry but there is lag, latency.
Jan 16, 2015 2:52PM PST
https://www.google.com/search?q=bluetooth+packet+transmission+time&ie=utf-8&oe=utf-8 shows this is on the web.

As long as your design demands no lag or latency it's nothing I would want to go for. I've seen companies go down that path and it's not pretty.

I'm sure folks new to this would write it will be OK.

-> Why the fixation with bluetooth? For this I'd be looking at WiFi since even at 802.11g that 54 megabits a second, a lot more connections and a lot more range.
Bob
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also....
Jan 13, 2015 3:14AM PST

also, what about if I wanted to connect 7+ bluetooth devices to one master device?
I know they say you can only connect 7, and thats totally cool, but what if I wanted to connect more?
also, if they all are connected, and they switch a bunch of times, could it be said they all will
transmit their signals one after the other? will latency be present (this is a time sensitive project, where
latency is the enemy lol).....

anyone know? need more info?

let me know!

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As the author
Jan 13, 2015 3:17AM PST

You can write the app so it's a server and connections come and go as needed. This is something your app's author can implement. Only those new to apps would think you need to pair, connect and stay connected.
Bob

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If latency is an issue. The Bluetooth Piconet
Jan 13, 2015 3:34AM PST
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so if there are.....
Jan 13, 2015 9:23PM PST

so what if there are 1600 signals floating around at one area at any given time?
how many MAX signals will someday be available at a time?
but what then does that mean if there are only 40 channels available?
40 2mhz channels for 4.0 right?

also, what if there are bt3.0 devices around? they probably will experience more interference right?

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How many at a single point in time.
Jan 14, 2015 12:46AM PST

This may sound odd but at any one point in time there can only be one. I'm guessing you are just starting out so you'll have to get out there and make this system to learn why it all works.
Bob

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And why Bluetooth?
Jan 13, 2015 3:37AM PST

A recent project has use using Rasberry Pi's with WiFi and that's pretty nice. Low cost, great dev kits and more.

No limits.
Bob

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Now that we're over zero lag.
Jan 18, 2015 4:37AM PST

Now you write something about broken if it doesn't work. Let me share something that old systems fail to consider at times. Ready?

Configuring. A recent system required techs to setup each module. The company hadn't thought of self configuring networks. So here they are, shipping and flying techs out to configure each little box in the system. If only they had not fixated on the cost of the box so hard that they lost all those savings in field support.

Anyhow, it appears this is research so my last input here is to get a great team together and let them redesign this thing. Sounds like the original planner/creator got hung up on bluetooth.
Bob

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check this
Jan 30, 2015 3:05AM PST

The battery usage all based on your mobile applications consuming it. Check in your settings and battery and check the consuming percentage based on the application. If any unused application consuming battery means, you can go ahead and stop that particular application.

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Bluetooth Battery Consumption
Jan 30, 2015 11:32AM PST

The battery usage is a measured by the amount of applications that are running on your phone. Check the settings on your phone for your battery and look at the percentage of use for each application. If you have a lot of applications running the battery will drain faster. Close out the applications you are not using under the settings area.