As the latest WiFi standard, 802.11ac, starts to gather pace in the technology’s conventional bands, 2.4GHz and 5GHz, the ecosystem is also increasingly interested in new spectrum options.
WiFi’s need for additional capacity may not be as imminent or urgent as 3GPP technologies’, but congestion in the overused 2.4GHz band is a rising concern, especially with the increasing investment in enterprise and carrier-class services that are still relying on license-exempt frequencies.
The highest profile new band for WiFi is 60GHz, where the 802.11ad standard lives. This technology is assembling a credible ecosystem thanks to its deepening convergence with mainstream WiFi. However, there are many other bands under consideration. Globalstar is trialling TLPS (terrestrial low power service), effectively WiFi in a licensed band, the 2.4GHz mobile satellite frequency adjacent to 802.11’s territory.
Another important option is to run WiFi in TV white spaces spectrum, though several other protocols are vying for attention there too. One sign of the future was seen at Japan’s National Institute of Information and Communications Technology (NICT) recently, when the institution showed off a tablet which can run both 2.4GHz and TV white space (470MHz to 710MHz) connections.
The Android device is an off-the-shelf design except for its NICT-developed frequency converter for using TVWS spectrum. “Radio communication in both TV and 2.4 GHz bands is available with an original WLan system (802.11b/g) and internet access is also possible through the white space WLan base station developed by NICT,” said the body.
Now WiFi is also eyeing 900MHz as part of its bid to elbow out other protocols in the growing market for home and building automation, and the internet of things. This is based on the upcoming 802.11ah standard, which will power commercial chips from 2015, but which will have to find its place alongside 60GHz, Z-wave and other 900MHz options, notably ZigBee ‘ which, in the reverse process to WiFi’s, has added 2.4GHz support recently to boost capacity, as well as IP.
A first vote on the 11ah standard could come this month but the standard might not be finalized until early 2016, though as with other WiFi generations, vendors are likely to bring pre-standard products to market as soon as the draft is close to stable. That means new chips are expected sometime next year, with members of the IEEE taskgroup likely to be in the vanguard ‘ a Qualcomm engineer leads the group, and other participants come from Broadcom, Huawei, Intel, LG, Marvell, NEC, Samsung and ZTE, according to EETimes.
The latest addition to the WiFi/802.11 family aims to support a wide range of performance options, from 150Kbps in a 1MHz band to 40Mbps over an 8MHz band. Distances could be 50% longer than those of current 802.11n products because of the low frequency used. Supporters claim it will provide a simplified platform, with one radio and one router that could cover a wide range of use cases.