ITEM: A start-up company claims to have made a serious breakthrough in power amplifier technology that could not only double battery life in smartphones, but also save cellcos a bundle in base station power costs.
Eta Devices, a spinout company from MIT, says it’s developed a new amplifier design that’s far more efficient than current designs. That’s potentially big news because power amps – the things that turn electricity into a radio signal in things like base stations and mobile devices – are major energy wasters.
According to Technology Review, almost two-thirds of the energy consumed by a power amp goes to waste because they use transistors that consume power in two basic modes: standby mode and output signal mode. The lower the standby power, the more efficient an amp is, but switching from low-power standby to high-power output mode tends to distort the signal, so the only solution is to keep standby power high, which wastes electricity. That’s why power amps tend to account for 67% of base station power consumption, for example.
Eta’s solution is “asymmetric multilevel outphasing” – or, as TR describes it, “essentially a blazingly fast electronic gearbox”:
It chooses among different voltages that can be sent across the transistor, and selects the one that minimizes power consumption, and it does this as many as 20 million times per second.
The problem they are attacking affects not only when you are literally transmitting something, but also when you are receiving. In the latter situation, the amplifier is busy as the device continually sends out messages confirming the receipt of packets—collections of bits that make up a unit of Internet communications—or alerting the network when packets are missing.
Eta reportedly hopes to formally launch the technology at next year’s Mobile World Congress in Barcelona and go commercial with it the same year. The initial target market will be base stations for developing markets that need more power-efficient base stations in rural areas, but Eta is also aiming for the smartphone market, TR reports:
It hopes that its work on a smartphone chip will ultimately lead to a single power amplifier that can handle all of the different modes and frequencies used by the various global standards, such as CDMA, GSM, and 4G/LTE. (Inside an iPhone 5, for example, there are currently five such chips.)