Linley on Mobile
Wireless Wants to Wallop WiresFebruary 20, 2012
Author: Tom R. Halfhill
Video is the Internet’s killer app—that is, the app that is killing our networks with a barrage of bits. Wi-Fi, the dominant home-networking technology, easily handles email, web browsing, messaging, music, and other legacy apps. But today’s 802.11n routers can hiccup when streaming 1080p HD video, and new technologies like 3D-TV and 4K-HD resolution demand still more bandwidth.
Consequently, home-theater enthusiasts risk their security deposits and marriages by punching Cat5e Ethernet cable through the walls. Their savior may be Wi-Fi’s next generation: 802.11ac. This pending standard is fast enough to distribute multiple HD-video streams to TVs, PCs, Blu-ray players, smartphones, tablets, and videogame consoles throughout a home.
Right now, 802.11ac is not quite a standard; the official seals of approval from the IEEE and Wi-Fi Alliance are expected later this year. But the draft specification is close enough to final that companies like Broadcom, Quantenna, and Redpine Signals are already introducing the first 802.11ac chipsets and other building-block products.
The big news about 802.11ac is that it’s the first Wi-Fi candidate with enough sustainable bandwidth to seriously challenge Gigabit Ethernet, which is why it’s often called “Gigabit Wi-Fi.” It has the potential to obsolete wired LANs in homes and small offices, though probably not at larger sites. We’ve heard such claims before, but 802.11ac has enough improvements to be credible.
In addition to providing more bandwidth, 802.11ac could deliver greater effective range and consume less energy per bit. Some of its promised benefits are unproven in real-world applications, however, and it also demands more peak processing power from the transceiver and host CPU. Another caveat is that some systems needing high bandwidth may be unable to physically accommodate the multiple antennas required.
Nevertheless, 802.11ac is on its way. Transceiver chipsets are sampling now, and hard macros, software stacks, and reference designs are available. The first consumer products may appear later this year, presaging a flood beginning in 2013. On the assumption that mobile devices will use 802.11ac, In-Stat predicts that the new standard will follow the same hockey-stick growth curve as previous Wi-Fi standards, with shipments soaring to one billion units by 2015.