Wireless-local-area-network (WLAN) services have become vital to many users. Many businesses, such as transportation companies and restaurants, often tout their free WLAN services to lure new customers. While the most familiar WLAN services take place with the lower industrial-scientific-medical (ISM) frequency bands (such as 2.45 GHz), a WLAN standard with the latest promise, IEEE 802.11ad, is centered at 60 GHz. For those interested in this latest version of WLAN, a 28-page application note from Agilent Technologies, "Wireless LAN at 60 GHzIEEE 802.11ad Explained," provides an excellent overview of the standard, the groups behind it, and the equipment that will be needed to test equipment for it.
As WLAN users have developed the need for faster data rates in sending larger data and video files, the performance levels offered by 60-GHz WLAN systems appear more attractive for short-range communications. The lower-frequency WLAN standardssuch as IEEE 802.11a, with data rates to 54 Mb/s at 5 GHz, and IEEE 802.11b, with data rates to 11 Mb/s at 2.4 GHzprovided sufficient performance until users wanted to send more data through these wireless networks. The file-transfer speeds of these earlier standards were somewhat limited for sending large files. With data rates exceeding 100 Mb/s at 60 GHz, this new WLAN version offers great promise.
The 60-GHz band is relatively uncongested, but also suffers more free-space path loss than WLAN systems operating at lower frequencies. Of course, this limited signal propagation at 60 GHz can also be a benefit for users concerned about the security of their transmissions. After all, the rapid signal loss makes it more difficult for unwanted users to intercept a signal.
The application note covers the benefits and shortcomings of operation at 60 GHz, along with some of the typical operating limits in terms of distance for a given transmission power. It also details the work of the WirelessHD Consortium, which was founded in 2006 to develop and promote an industry-standard, next-generation wireless digital interface specification for consumer electronics, personal computers (PCs), and portable electronic products.
This new 28-page application note, No. 5990-9697EN, is available as a free download (in PDF format) at www.agilent.com/find/802.11ad.
Agilent Technologies
5301 Stevens Creek Blvd.
Santa Clara, CA 95051
(408) 345-8886
www.agilent.com.