I want to measure how much battery is consumed while switching on Wifi, scanning and connecting to a an AP. I tried doing it with the API to see battery level. But that API gives battery level on a scale of 100 which is not granular enough to find out the power consumed in turning on the Wifi and scanning only once.
Is there a way out to measure this?
If you want to measure the power consumption in you phone and if you can do it using hardware I would suggest this:
http://www.adafruit.com/products/904
It's a Current and Voltage sensor board, easy to use with an Arduino board. I've used it to get fine grained values every 6ms.
PowerTutor need to be calibrated (using hardware or datasheet values) for each device if you want to be accurate.
I don't think there is any such API to do this for WiFi. You'll have to use alternatives :
Use a multimeter/ammeter setup
Read the current value from the system
Buy some really expensive equipment designed specifically for this purpose
Use some third party apps that measure power
You should read the value in /sys/class/power_supply/battery/batt_current.
That's the current consumption of the phone in mA. It's updated by the OS every minute or so.
Check out Powertutor. It is in my experience the best application out there to measure power consumption. It is not 100% accurate but is good enough for estimations. You can categorize by 3G, CPU, Wifi.. etc.
Related
For a research project I need to measure the power consumption of some functionality. So I would like to measure the power consumption of a method. For example: method computeSomething() needed x microampere-hours. Is this possible? If yes, how?
I tried to measure the remaining battery capacity in microampere-hours and the remaining energy in nanowatt-hours before and after execution with the BatteryManager. But this isn't accurate enough. Is that even possible to do it?
this is what i tried:
mBatteryManager.getLongProperty(BatteryManager.BATTERY_PROPERTY_ENERGY_COUNTER);
EDIT:
for sure it's the emulator which don't consume energy and that's why I get a consumption of 0. Is it possible to simulate power consumption with the android emulator or do I need a real phone?
Here's how I would measure the energy used (because that's what you want and not power).
Shutdown (or don't use) everything I can, including network, cell, USB, etc.
Disable any power saving features on the phone
Log any data you get on the phone's file system (vs through the USB or wireless)
Wrap the program in a large loop that makes its runtime at least a few seconds, perhaps a few minutes
Run the test program you just made many times (>=16 times for statistical significance)
Measure the phone at rest over the same amount of time and collect the energy used.
ANALYSIS: (and you need to do this)
Check on the statistical deviation (std dev) of both your function run and the "at rest" run. If the std dev is large, something else is going on that is using energy.
Find out the resolution of BatteryManager. Just because the field is labeled in nWatts doesn't mean the hardware measures it at that resolution (and it probably doesn't). The people who develop a data structure want that structure to be useful on a lot of hardware and for the foreseeable future. Thus they make the field measure in something very small (e.g. nWatts) even if most hardware can only measure at best, say, in tenth of watts.
If possible, use a hardware interposer between the battery and the phone to measure energy/power directly. This gets around the uncertainty in the implementation of BatteryManager.
Just to be safe, you might also find out how long of an integration window the BatteryManager uses for measuring power. These measurements usually involve a moving window for computing averages.
An emulator isn't going to give you any useful information. Emulators test functionality and little else. Even a rough measure of performance is very iffy.
I've developed a similar App before but is used to evaluate the power consumption of each Application. But as far as I know, the Google's battery static API evaluate power consumption according to each UID, both hardware and software. I think you can find more information by looking into the source code of Android, especially for BatterySipper.java and BatteryStatsHelper.java.
For emulator, Android system uses power_profile.xml as reference to calculate the power consumption. This file is usually modified by manufacturer. Maybe it's not included in emulator.
I'm developing android app using OpenCL for CPU-GPU parallel computing. I want to measure CPU-GPU each power consumption or total power consumption in app execution. But I can't find proper measurement method.
The Android Developer site provides you with all you need :
https://developer.android.com/training/monitoring-device-state/index.html
You can :
1.Monitor the Battery Level and Charging State
2.Determine and Monitor the Docking State and Type
I have used ODROID-XU to measure energy consumption in CPU and GPU.
They provide power sensors for the 2 CPUs, GPU, and memory.
I have made a few scripts for collecting and analysing such data. Available here:
https://github.com/luiscruz/greenbenchmark
This is a good approach if you need reliable measurements.
On the contrary, software-based approaches only provide an estimation which might not be accurate.
I want to calculate distance Bluetooth Paired device from android mobile. I am new in Android Bluetooth Concept can any one suggest me it's possible or not possible in android sdk.if it's possible post any code or tutorial link!
The Bluetooth signal strength distance relation depends on the devices (built-in Bluetooth device, antenna, actual orientation of device), current way the persons hold their devices, objects in-between... You could measure this for a pair of devices for a given situation and use these information.
A larger and more general solution would incorporate an external Bluetooth network. Bluetooth triangulation is the basic concept, that will help. The link will give an insight on certainties that are achievable with such a setup. Take is as an upper limit, a device to device approach will be worse.
The EE Stack Exchange site has a more complete answer which includes a mention of Apple using 802.11v for determining if Apple Watch is close to a MacBook.
Bluetooth uses radio, and radio travels at the speed of light. A 1cm round trip will take less than 100ps. Timing something that short will be tricky, probably you'll want a 10GHz clock, though there are other options. But even then, Bluetooth isn't designed to instantly echo the radio message. If you receive, process and re-transmit the message, then the processing delay will be much longer than the time of flight, and will vary randomly by at least the period of the clock used with the Bluetooth chip.
You can't. Maybe, you can get approximate value from signal indicator but it's too much subject because of envirounment - is there something between connected devices, some reflection surfaces, etc.
There is a way you can research, is coding a response time. just calculate the bluethooth response time in nano secs, physically measure the distance between the devices and make a tree rule... is the same concept of GPS. This is a Laboratory work. I have a project that i have to develop it, in schedule i will taking it in a month.
OFC, its possible. It just requires ultra precise app, build to calculate "pings" between the two objects - kinda like ekko-location or laser distance measurement - its about how much time a specific signal travels back and forth.
I'm looking for a list of all the components and their power drainage on an up-to-date smart phone.
Accelerometer, gyroscope, magnetometer, etc.
Display
WiFi
Bluetooth
GPS
CPU
Camera
Microphone
etc.
Preferably in mA so it can be easily compared to the battery's capacity (usually specified in mAh).
The Sensor's power is actually available via the SDK and can also easily figured out for most devices on AndroidFragmentation. However what I'm looking for is comparable data for the other hardware components to consider their efficency.
Bonus: Will a request for less frequent updates of a Sensor decrease energy consumption of the Sensor, as it returns only one value for getPower()?
There are a couple of detailed studies that I am able to find on this.
A study from the USENIX meeting in 2010 which studies various components of a smartphone (except the camera)
Another study from the Hotmobile mobile computing workshop 2013 that has more information on cameras and displays.
Reference 1 especially seems a great starting point.
I'm looking for a list of all the components and their power drainage on an up-to-date smart phone.
That is impossible to answer.
First, different devices will use different varieties of these components, with different power characteristics.
Second, many, if not most, of those components will have no published power statistics, or the specific components themselves may not be knowable without a complete teardown of a device.
Will a request for less frequent updates of a Sensor decrease energy consumption of the Sensor, as it returns only one value for getPower()?
That will depend on the sensor. Some sensors are effectively always "on" (e.g., ambient light sensor), courtesy of the OS, in which case the only incremental power drain for your use of that sensor will be in passing that sensor data to your process. Other sensors might not be regularly used by the OS, meaning that your request for events from that sensor might turn it "on", resulting in power drain from the sensor itself in addition to supplying you with that data.
It would be truly wonderful if all Android devices were instrumented in the way the Qualcomm MDP is, so that we could get fine-grained power detail for our apps and their usage of various components.
There was a Google I/O session on this very subject a few years ago; you can see the video here and slides pdf here.
I know it's against the rules to plug your own startup, but what you're asking sounds exactly like what we're working on.
There's an Android performance monitoring tool called "Little Eye Labs". It shows real-time power consumption of an App as it runs on a phone. It currently only supports CPU, Display, GPS, Wifi and 3G, but you'll be able to get the instantaneous power consumed (in mW) by these components.
/end of plug
Note that there's no real way to get this information directly from a device, so the best you can do is model the phone, gather device resource consumption, and model power usage.
Display is the most power consuming part of the smartphones; accounting for up to 60% of total battery life (Can draw power up to 2W). There is a book called Green IT and its Applications; you can read it online in Google books.
On any modern Android, go to Settings > Battery (sometimes Settings > About > Battery). You should see a graph of power drain over time, as well as how much was used by what component.
Although consumption varies a lot based on usage patterns, in my experience the top consumers are display, radio, and CPU. I have not seen sensors rank high in energy use on any of my devices, in the absence of bugs. The link provided by Yusuf X places game sensors above CPU.
For more information about optimizing battery use on Android, see Reducing the battery impact of apps that downloads content over a smartphone radio and Optimizing Battery Life.
There is an app called PowerTutor that it does some battery consumption measurements for every phone component and for every process. The code is open so you can pick up some ideas from there. Note that this app was optimized for Google's phone, especially for the Nexus One.
I need to perform power measurements for android applications. I tried "powertutor" and it gives the power consumption per every application. Yet, I don't know how accurate its readings are. Does anyone know how accurate it is?
Also, I have used the DDMS to profile the android application. I obtain the processes as memory info about it. Is there a way that i can know the power consumption per process in Android? (some rough estimation?) or is it impossible?
I really need to perform "power" profiling for android applications but I don't know how.
In my academic research for measuring power consumption on Android, we use a power supply hooked up to the phone's battery terminals that outputs the voltage and current to a PC. Measure without the app to get a baseline and then compare against measurements with the app running. It's not extremely accurate, but it's the best way we know how.