MIT researchers double battery life ( Aplicable to Smartphones )

Fudzilla ^ | Monday, 05 November 2012 10:56 | Nick Farrell

[Ernest_at_the_Beach]

Sorting out the amp in a mobile phone

Two MIT researchers claimed that they have doubled the life of a mobile phone battery by tweaking an efficiency problem related to the power amplifier.

The professors Joel Dawson and David Perreault claim that power amplifiers are to blame for much of the draining of a mobile phone and the amp chips waste as much as 65 per cent of their energy. They have formed a startup called Eta Devices which will flog gear that they claim to have solved this problem.

The technology is currently being tested in labs. They think that if it is adopted base station energy usage will be down by 50 per cent and once a chip-scale version of the technology is developed and commercialised, smartphones will have double the battery life.
At the moment transistor based power amplifiers consume power in standby and output signal mode.  The only way to reduce power consumption and increase battery life is to use the least possible power when in standby.

But if the power is kept too low when in standby mode the sudden introduction of power creates a signal spike and the sound is distorted. This means that standby power levels are kept at a relatively higher level to avoid distortion, but this also costs a lot of electricity. Dawson said that the problem gets worse with high data rate communication,  because you need more standby power than signal power.

The pair's technology is called asymmetric multilevel outphasing which works like an electronic gearbox that would select the best possible voltage to send across the transistors that would minimize power consumption. It can do this at about 20 million times per second.

[bmwcyle]

Excellent

[Da Coyote]

Hmmm, have not the time to check, but this sounds a lot like Bob Carver’s old Sunfire Cube amp technology - playing with the power supply in an audio amp to increase efficiency and (as a byproduct) decrease the size. Not sure if he varied powersupply voltages to the output stage, or if he was using some sort of digital switching...but methinks he might be have been 20 years or so ahead of these folks.

[PA Engineer]

This will have far more applications than just cell phones.

[Revolting cat!]

Just about every month we hear this kind of news. This is the magic discovery for the month of November. Then golden silence.

[Ernest_at_the_Beach]

I read this as something that would be mostly applicable to SoC transistor devices.....

[BereanBrain]

there is so much bad science in this article.

Battery life has NOTHING to do with amplifier technology.

The article should be titled ‘more efficient RF power amplifier developed’

And, BTW, I don’t believe the claim either. If you want super efficient, low power RF, we already have that technology, it’s just that the cell providers don’ t use it.

Not a technology problem, a business issue.