The inside scoop on how fast-growing Georgetown, Texas leverages Siemens RUGGEDCOM WIN point-to-multipoint wireless WiMAX communications technology.
Georgetown is the county seat of Williamson County, Texas, with a population of over 50,000. In just over a decade, the town’s population has doubled, challenging its infrastructure to efficiently provide water, sewers, electricity, and roads. That responsibility rests with Georgetown Utility Systems, one of the largest and most critical departments in the city government.
“It’s not enough to just ‘stay up’ with the city’s growing number of citizens, because that would mean we’re always behind the curve,” says Ron Marrow, Georgetown’s transmission and distribution supervisor for SCADA. “We have to stay ahead of the growth and that takes good planning.”
Standing Up to the Heat
A mission-critical task for Marrow’s department was to cost-effectively connect remote water treatment sites with faster, more reliable data transmission capable of withstanding the extreme heat of Central Texas summers. For years, Georgetown Utility Systems used the 900 MHz radio spectrum to monitor the many components of its water, sewage, and electrical distribution systems, using SCADA data communications with speeds of 9600 bits/sec. But Marrow explains that 900 MHz radio communications weren’t always reliable over a coverage area of approximately 300 square miles.
Hot weather was a particular problem, with average temperatures often exceeding 100 degrees Fahrenheit in July and August, and frequent highs in the 90s well into October. “Heat causes atmospheric changes that can disrupt radio data transmissions,” notes Marrow. “Whenever it got hotter than 90 degrees, for example, communications from a remote wastewater lift station would fail, so we’d have to send a technician to take data readings every four hours to make sure everything’s operating and nothing’s overflowing. If we’d have had an overflow, the actual environmental impact might not be all that big; but the regulatory reporting requirements would have been huge, so we had to have someone monitoring it in person.”
Another issue was the star topology of the city’s 900 MHz radio network. All the remote radios were transmitting back to one central radio. If that central radio went down, so would all communications.
To address these concerns, Marrow and his team designed and deployed a redundant, 1 Gbps fiber ring network for the city’s SCADA communications, with an eye toward using its multi-megabit bandwidth to eventually enable manifold broadband communications, including video surveillance, voice-over-IP, and remote, on-demand WiFi hotspots for municipal field workers. But before such services could be implemented, the department had to deal with a more immediate concern: cost-effectively connecting remote water treatment stations with the fiber ring.
A License to Succeed
The solution to the problem was to deploy high-performance Siemens RUGGEDCOM WIN technology to augment the city’s mission-critical broadband with licensed 4.9 GHz wireless capabilities. Because in-ground fiber costs up to $25,000 per mile, extending the city’s fiber to its wastewater lift stations up to seven miles away wasn’t economically feasible. Broadband wireless was the only way to go, so that the fiber ring’s multi-megabit throughput could extend to the remote sites.
- Commercial cellular networks
- 11 WiFi
- 16e WiMAX, using the 4.9 GHz spectrum the FCC allocated to public safety and municipal uses, which also allows for mobile connectivity.
The problem with the first option was monthly charges. The second option had limited range. The third option was determined to be the best, but required FCC licensing and documentation that Marrow and his team had no experience with.
They turned to Siemens for assistance. In building out its fiber ring, Georgetown had deployed scores of RS900G Layer 2 switches from RUGGEDCOM, a harsh environment communications portfolio from Siemens. The RS900G is an environmentally hardened, fully managed Ethernet switch that provides dual fiber optical Gigabit Ethernet ports with Gigabit uplink ports, and 128-bit encryption. In all, the city had deployed more than 200 RUGGEDCOM devices in its fiber network, including routers and media converters. “We had all these RUGGEDCOM devices in our network already, so it only made sense to keep all the WiMAX components in the family, too,” notes Marrow.
Through its work on the fiber ring buildout, Siemens was well aware of the issue of extending the fiber’s broadband throughput to remote sites. They also knew that the WiMAX technology had some line-of-sight challenges in connecting wastewater lift stations that are typically placed in low-lying areas amid Georgetown’s rolling, tree covered terrain. “So we not only needed help securing our FCC license, we also needed some excellent RF engineering system design and integration,” Marrow recalls.
For both these services, Siemens recommended Austin, Texas-based Alpha Omega Wireless, a specialty systems integrator and Siemens-certified Industrial Wireless Solution Provider. Working closely with Marrow’s team, they compiled a detailed set of requirements that led to a RUGGECOM point-to-multipoint 4.9 GHz WiMAX solution as well as a comprehensive deployment and commissioning plan. They also processed all the paperwork needed for the city’s FCC license, saving significant time.
Putting the Solution in Place
The RUGGEDCOM WIN WiMAX solution has three components:
- A RUGGEDCOM WIN 7249 small form-factor base station, specifically designed for 4.9 GHz radio transmissions
- A RUGGEDCOM WIN 5249 outdoor subscriber unit, also designed for 4.9 GHz spectrum
- A RUGGEDCOM RP100 single-port 802.3xx Power-over-Ethernet (PoE) injector that powers the other two devices
All RUGGEDCOM gear is utility-grade equipment designed, tested, and field-proven to work in environments subject to high electromagnetic interference (EMI), extreme temperatures, and environmental pollutants. It’s also been put through Accelerated Stress Testing, comprising Highly Accelerated Life Testing (HALT) and Highly Accelerated Stress Screen (HASS), both designed to find defects before environmental conditions do. These tests enable Siemens to provide five-year warranties on everything in RUGGEDCOM’s broad portfolio of network components.
For Georgetown, the results include an extremely reliable, future-ready, high-bandwidth wireless network; thousands of dollars in labor cost savings; and hundreds of thousands of dollars in cost-avoidance.
In the first phase of deployment, which took just two days, Alpha Omega Wireless installed the WIN base station in one of the city’s outlying, 120-foot water towers to have a clear line of site to its corresponding subscriber units installed in four remote water treatment stations, the farthest being more than five miles away. Marrow says he was amazed at the difference in transmission speeds when he took his laptop in the field and logged into the 4.9 GHz SCADA data stream. “It was like night and day,” he says. “Before, the data speeds were so slow. It was like going from using a quarter-inch-wide pipe to a six-inch-wide one.”
Marrow says that the city will no longer incur the labor expense of dispatching a technician to waste water lift stations for logging data by hand whenever the outdoor temperature breaks 90 degrees. With more than 30 days a year of such temperatures, that adds up to several thousands of dollars a year in labor that the city will put to better uses. Those savings are small when compared to the city’s avoidance of hundreds of thousands of dollars in capital costs, had it decided to lay fiber in the ground out to the remote sites.Have an Inquiry for Siemens about this article? Click Here >>