A WiMAX Primer
This article appears in the August/September issue of Streaming Media magazine. Click here for your free subscription.
One of the few benefits of being part of the military conflict in Iraq is the opportunity to test and evaluate new technologies. Two years ago I had the opportunity to deploy wireless broadband networks, utilizing technology similar to "Mobile WiMAX" in and around the City of Fallujah during "Operation Al Fajr." These networks offered fast installation and a robust communications platform for voice, data, and video applications in an environment and terrain not suited for wired networks.
Historically, defense technology that has been transferred to the civilian sector has changed much of how the world works. Two examples are cellular communications and the internet. The wireless broadband technology coming out of this war will continue that tradition and have a significant impact on many industries, including streaming media.
WiMAX stands for Worldwide Interoperability for Microwave Access. The term WiMAX is the commercial name for the 802.16e-2005 protocol established by the Institute of Electrical and Electronics Engineers (IEEE). WiMAX uses a modulation technique called Orthogonal Frequency Division Multiplexing (OFDM), which was first developed for high frequency military communications systems during the 1950s. The name was assigned by the WiMAX Forum, which describes WiMAX as "a standards-based technology enabling the delivery of last-mile wireless broadband access as an alternative to cable and DSL."
WiFi is often confused with WiMAX. Unlike WiMAX, WiFi (802.11) is comprised of three versions known as 802.11a, 802.11b, and 802.11g. The first version, 802.11a, operates on the 5 GHz band and is typically used to install longer-range connections because the signal suffers less interference. The other versions, 802.11b and 802.11g, operate on the 2.4 GHz band and suffer interference from other household devices such as cordless phones and microwave ovens. These later "b" and "g" versions are the common variety that you might purchase at a retail store and plug into your home network. The 802.11g version has the longest distance and uses OFDM technology similar to WiMAX. An additional version, 802.11n, will offer even greater distances and speeds, but ratification by the IEEE has been delayed to late 2008.
As mentioned earlier, the WiMAX standard is based on the 802.16e-2005 protocol. In short, think of WiMAX as "WiFi on steroids" due to its increased coverage area over WiFi and low deployment costs compared to 3G networks. By comparison, a typical WiFi router can blanket a small house with wireless coverage while a WiMAX transmitter can potentially blanket an entire city (more than 20 miles) with broadband coverage.
Deploying Wireless Networks
Planning wireless networks is an art and a science. How a technology is deployed in a market is equally important to its intrinsic capabilities and limitations. All wireless technologies are based on simple principles such as frequency modulation (think AM vs. FM radio), power (more power = more distance), terrain (line of site vs. buildings), availability of quality frequencies (interference vs. access), and security (open vs. closed). The successful deployment of new wireless technologies must strike a careful balance of technology (WiMAX), suitable power output, available "airwaves" or frequencies, and careful placement of the transmitters in order to maximize coverage and quality, yet minimize costs.
As WiMAX technology is adopted in the global marketplace, it is important to understand that there are major corporate stakeholders that want this technology to succeed. Nobody cares more about the success of WiMAX than Intel, which hopes to create unlimited demand and new markets for its embedded wireless chips within the new WiMAX "ecosystem." It is a leader in the WiMAX Forum, which is comprised of 420 members including chipmakers, hardware manufacturers, network operators, and service providers. The organization’s purpose is to "certify and promote the compatibility and interoperability of broadband wireless products based upon the harmonized IEEE 802.16/ETSI HiperMAN (High Performance Radio Metropolitan Area Network) standard."
Standardization of the 802.16e will ensure interoperability while increasing competition among hardware manufacturers and driving down hardware prices for the consumer. As WiMAX is adopted on a global scale, competition is expected to rise, which will cause hardware prices to fall and exacerbate demand. A similar pattern was followed during the commercial adoption of WiFi in the consumer space.
Global momentum for WiMAX is notably strong and growing. In the United States, Clearwire launched in 2003 and now operates in 39 domestic markets and four international markets, offering 1.5Mbps download and up to 256Kbps upload speeds. Last fall, Sprint Nextel also announced that it plans to develop and deploy the first 4G nationwide broadband mobile network based on Mobile WiMAX. The infrastructure costs will be $1 billion in 2007 and $1.5-$2 billion in 2008.
Most recently, Intel announced that it will begin to provide WiMAX cards for notebooks during 2008. More than 20 WiMAX deployments are under development internationally as well.