Download: energy consumption for different technologies

Here we present the energy and power measurements for the different air interfaces, namely Cellular, Bluetooth, and Wi-fi.

 

Experiment details

Description:

Download 500 KB using different air interfaces.

Place:

Indoor.

Technology used:

Bluetooth 2.0+EDR, GPRS, HSDPA and IEEE 802.11b/g.

Number of tests:

250 downloads in total.

Notes:

During the measurements all the air interfaces not required are switched off.

 

In the Figures below the total energy and the energy per bit spent when downloading 500 KB with different technologies are shown. The energy is plotted against the datarate.

When downloading with WLAN, the connection was set in infrastructure mode. The distance from the AP is approximately 3-5 meters. To obtain several datarates for the different technologies, we have repeated the tests several time. We have noticed that there is no correlation between the datarate/energy and the received signal strength (cellular connection).

Energy for downloading 500 KB using different technologies.
Energy per bit for downloading 500 KB using different technologies.

Moreover, the Figure below shows that the power consumption for downloading 500 KB using different technologies slightly increases with the datarate.

Power consumption for downloading 500 KB using different technologies.

Parametrized model

E_bit [J/bit] = A+B*(Datarate - C)

E_tot [J] = Ebit *DataSize

  

Technology A B C Datarate range[Kbps]
GPRS 1.47E-05 -2.88E-07 3.33E+01 30-45
HSDPA 1.13E-05 -7.21E-09 1.01E+02 100-1500
Wi-Fi 6.45E-07 -1.27E-10 2.13E+03 2000-5000
Bluetooth 5.72E-07 -4.89E-10 6.85E+02 650-850

Department of Electronic Systems | Aalborg University | Niels Jernes Vej 12 | DK-9220 Aalborg | Denmark
Phone: (+45) 9635 8695 | Fax (+45) 9815 1583 | E-mail ies(at)ies.aau.dk
Copyright © 2006 Department of Electronic Systems

Last update:20-07-2011