Ever wondered why your phone is lot faster downloading data than uploading it? It has to do with transmit power. The cell tower is hooked into the electrical power grid, allowing it to pump out signals at hundreds of watts. The wee lithium-ion battery in your device can’t keep up, and it’s probably a good thing unless you want your phone to double as a BBQ grill. Consequently your phone is forced to make more petite low-power optimized transmissions, sacrificing upstream bandwidth in the process.
But network equipment maker Ericsson wants to even the score. It can’t reach parity between uplink and downlink capacity, but new network technology it plans to show off at Mobile World Congress in Barcelona next week will boost uplink capacity on HSPA networks by a factor of three, helping to shrink the ever-widening gap between downstream and upstream speeds.
Ericsson achieves this in two ways. First, through receive diversity, which is a fancy way of saying a butt-load of antennas on the tower (in this case four) gathering up the weak signals transmitted by the device. The second is a technology Ericsson calls Interference Suppression, which basically involves throwing a lot of complex math at those signals when they reach the base station. Out of the other side pops an uplink connection with a theoretical ceiling of 12 Mbps, which puts the 1-2 Mbps we’re seeing over today’s HSPA+ networks to shame.
Unlike other “We’re the fastest!” announcements that vendors like to make at MWC, there is no fine print in Ericsson’s pitch. It’s not throwing additional frequencies into the mix or loading up your phone with more antennas than a police-edition Crown Vic. Ericsson is talking the same handsets, using the same spectrum, over the same networks, albeit with some modifications to the base station software and an upgrade to the tower’s antenna mast.
Ericsson has completed lab trials of the technology and plans to do live demos at its booth (really its building – it’s renting a lot of space) at MWC. But there’s still no word on when the technology will be available for commercial deployments. The sooner, the better, though.
Asymmetric networks were fine for the early days of mobile data, when we were passive consumers of content on our phones. But the rise of mobile social networking has turned us into active creators of content. We’re uploading photos and videos from our devices almost as much as we’re viewing them. Download emails used to clog our airwaves, but now uploaded tweets and Facebook updates are doing the same. And new real-time applications like video chat and multi-player mobile gaming require intense upstream connections.