New power amplifier design could double smartphone battery life
By Dave LeClair
November 5, 2012
Cell phones have come a long way in terms of battery life, but lets be honest, there's still plenty of room for improvement. The very fact that we talk about using a phone for eight hours as being good is, well, bad. While next-gen battery technologies present one solution to the dilemma, a new breakthrough from MIT spinoff Eta Devices takes a different tack – by improving power amplifier efficiency the company hopes to double the battery life of smartphones.
A power amplifier is the device required to turn electricity into radio signals, they are found in both phones and base stations, and they are incredibly inefficient. It's this drain that Eta Devices is aiming to plug with a new power amplifier design.
In cellular base stations, a huge amount of power is wasted during standby mode. The transition from low-power standby mode to high output mode tends to distort signals. Because of this, most base stations keep standby power high to prevent this distortion. Eta Devices' solution is described as an blazingly-fast electronic gearbox. It can choose different voltages as fast as 20 million times per second using a technology the company is calling this asymmetric multilevel outphasing.
Eta Devices is working on a larger power amplifier for base stations and a smaller one for individual phones. Currently at prototype stage, the technology is initially being targeted at LTE base stations and could see a commercial launch next year. Eta's research could also lead to a single power amplifier able to cope with different global wireless communication standards. Source: MIT Technology Review