This page contains measurements of power consumption for various GSM modems. Will hopefully grow in time as I get more of them. Recommended reading

Measurement method

The devices were powered from an isolated Uni-T UTP3701S power supply through two 1Ω 1% resistors in parallel, connected to my (also isolated) laptop. Rigol DS1054Z was connected across the resistor and configured to use the correct units and to sample the input channel in high resolution mode. The values here are RMS of the measured current.

The SIM card used was from mobil.cz, which is a reseller of T-Mobile in the Czech Republic.

Note: These measurements were taken with somewhat crude instruments, beware.

Comparison

Idle

All radio functions disabled with AT+CFUN=4.

               0mA                 100mA
Huawei E3131    [######..............] 30mA

Connected idle

Not transmitting/receiving any data.

2G

               0mA                 100mA
Huawei E3131    [########............] 40mA

3G

               0mA                 100mA
Huawei E3131    [#########...........] 45mA

Light traffic

Traffic produced by pinging remote server (ping used with default options as provided by the net-misc/iputils-20121221-r1 package in Gentoo).

2G

               0mA                 400mA
Huawei E3131    [########............] 160mA

3G

               0mA                 400mA
Huawei E3131    [######..............] 120mA

Medium download

Traffic produced by wget --limit-rate=4kB as 4kB is the download speed mobil.cz limits its customers to after the FUP runs out.

2G

               0mA                 400mA
Huawei E3131    [#########...........] 175mA

3G

               0mA                 400mA
Huawei E3131    [########............] 165mA

Heavy download

2G

               0mA                 400mA
Huawei E3131    [###########.........] 215mA @ 30KB/s

3G

               0mA                 400mA
Huawei E3131    [##########..........] 192mA @ 1.7MB/s

Medium upload

Traffic produced by dd if=/dev/urandom | pv --rate-limit=2k as 2kB is the upload speed mobil.cz limits its customers to after the FUP runs out.

2G

               0mA                 400mA
Huawei E3131    [#############.......] 255mA

3G

               0mA                 400mA
Huawei E3131    [#########...........] 174mA

Heavy upload

2G

               0mA                 400mA
Huawei E3131    [##############......] 258mA @ 20KB/s

3G

               0mA                 400mA
Huawei E3131    [#########...........] 188mA @ 500KB/s

Individual devices

Huawei 3131

Two inrush current events right after connecting, this probably breaks the USB specs

Idle, the two small peaks are the LED blinking.

2G idle

3G idle

2G light

3G light

2G medium download

3G medium download

2G heavy download

3G heavy download

2G medium upload

3G medium upload

2G heavy upload

3G heavy upload