San Diego wireless net installs 72-mile, 2.4-GHz link
Computerworld - Most enterprises that deploy wireless LANs estimate their coverage area in terms of hundreds of feet.
Hans Werner-Braun, a researcher at the San Diego Supercomputer Center and principal investigator for the San Diego County High Performance Wireless Research and Education Network (HPWREN), plans and develops wireless circuits that routinely span miles, including HPWREN's current distance-record holder, a 72-mile-hop installed last month from San Diego to San Clemente Island.
Although standard 802.11b WLAN gear operating in the unlicensed 2.4-GHz frequency serves as the baseline hardware for the new network, Werner-Braun said that HPWREN, backed by grants from the National Science Foundation, uses far-from-routine hardware configurations to serve rural San Diego County.
The link to San Clemente Island -- used to carry data from a seismograph, data logger and Global Positioning System receiver -- runs with the maximum 1-watt power output allowed by the Federal Communications Commission for 2.4-GHz equipment, Werner-Braun said. At both ends of the link, HPWREN technicians installed high-gain, 2-ft. parabolic antennas to provide an additional boost to the signal.
Although the raw data rate for the 802.11b gear Werner-Braun uses -- Orinoco routers and bridges from Proxim Corp. -- for the San Clemente Island shot is 11M bit/sec., the extreme distance cuts the throughput on that link to 1M bit/sec. But since there are no other communications alternatives, that's still a good data rate for an installation whose fixed cost ran about $3,000, according to estimates by Robert Ma, a product manager at Sunnyvale, Calif.-based Proxim.
Low costs, ease of installation and no hassles with protracted FCC license proceedings are the hallmarks of HPWREN, which uses equipment operating in both the 2.4- and 5-GHz bands to provide broadband data service to scientific installations, schools and Indian reservations scattered throughout 10,000 square miles of rural San Diego and southern Riverside counties in California.
Despite a large population hugging the Pacific Coast, rural San Diego County includes some of the most telecommunications-starved areas of the U.S., including the Anza-Borrego Desert, "and you're not even going to get a phone line in the desert," Werner-Braun said.
"There's no other viable choice" for high-speed access for scientific installations such as the Palomar Observatory besides HPWREN, which an can easily, quickly and cheaply install wireless connections to backbone nodes on mountains such as Alliance Peak, Toro Peak and Monument Peak, he added.
The backbone nodes operate at a data rate of 45M bit/sec. in the same unlicensed 5-GHz frequency bands used by 802.11a WLAN equipment, with high-gain, 8-ft. antennas pushing the distance from



- Excel 2010 Cheat Sheet
- Register for this Computerworld Insider Cheat Sheet and gain access to hundreds of premium content articles, guides, product reviews and more.
- Digital Transformation: Creating New Business Models Where Digital Meets Physical
- Individuals and businesses alike are embracing the digital revolution. Social networks and digital devices are being used to engage government, businesses and civil...
- Empowering Your Mobile Worker
- Today's most productive employees are mobile, and your company's IT strategy must be ready to support them with 24/7 access to the business...
- An Interactive Guide: Bring Your Own Device
- BYOD presents significant security and management challenges to IT departments who want to take advantage of the trend, but still protect corporate assets....
- Calculating ROI for Mobile Client Acceleration
- As mobile devices continue to expand in business use, ensuring these devices have optimal performance is becoming an IT imperative. This EMA paper...
- Tablet Computing Without Compromise
- This paper provides an overview of how and why that migration-from any old tablet to Windows tablets-came to be. All Mobile and Wireless White Papers
- Live Webcast
North Pole to South Seas: Overcoming the Pitfalls of remote Performance - In today's always-on world, connectivity is a business requirement. You need the tools that allow you to operate as if you were on...
- Supporting Mobile Productivity With A Limited IT Budget
- Join us and hear from Kaseya mobile IT management experts as we discuss core strategies for supporting the mobile revolution on a shoestring...
- North Pole to South Seas: Overcoming the Pitfalls of remote Performance
- In today's always-on world, connectivity is a business requirement. You need the tools that allow you to operate as if you were on...
- Unified Communications 101
- What's the best way to implement a unified communications solution for your organization?
- QNX® and BlackBerry® PlayBook™ Tablet.
- RIM's multi-processor, multi-tasking BlackBerry PlayBook runs a new Tablet OS powered by QNX, a bullet-proof microkernel operating system. This track will take a...
- A Close Look at Tablets
- Learn More All Mobile and Wireless Webcasts