Almost everyone who owns a smartphone would have noticed that whenever they stream videos or play games their device gets warm and starts to drain battery rapidly. Engineers claim that power amplifiers are to blame for this behavior and that these chips waste as much as 65 per cent of their energy. The professors Joel Dawson and David Perreault, through their startup Eta Devices claim to have solved this problem with a new power amplifier design.
The technology is currently being tested in labs but, according to the professors, if all tests go well, base station energy usage will be down by 50 per cent and once a chip-scale version of the technology is developed and commercialized, smartphones will enjoy double the battery life.
Current transistor based power amplifiers consume power in two modes – 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 mode. The problem here is that if the power is kept very low when in standby mode, because of sudden jumps from low-power standby mode to high-power output mode, signals get distorted. This is why current technologies waste a lot of electricity as standby power levels are kept at a relatively higher level to avoid distortion.
“It means you are pulling a lot of energy just to keep the thing on,” says Dawson. And the more data you need to send, the worse it gets. “With high data rate communication, you wind up needing far more standby power than signal power. This is why the phone is warm,” he says.
The new technology, dubbed asymmetric multilevel outphasing [PDF], is basically a super fast electronic gearbox that would select the best possible voltage to send across the transistors that would minimize power consumption. This process is done as many as 20 million times per second.