Wilmington, North Carolina and the county of New Hanover (NC) are using the frequencies from the vacated TV white spaces for a variety of wireless applications that save money and protect the environment. The partners in this “smart city” wireless network project are TV Band Service LLC, and Spectrum Bridge (a company that wireless networks to access and use all types of spectrum a database driven cognitive network architecture). TV white spaces are the unused TV broadcast channels made available by the recent transition from analog to digital TV. The Wilmington/New Hanover County area was selected for this trial network because it was the first major TV market in the nation, as selected by the FCC, to convert from analog to DTV broadcasting.
According to Wilmington Mayor Bill Saffo, the city has a fiber network to support municipal applications, and they are now using wireless technology (over the TV white spaces) where they cannot deploy fiber, for example, in environmentally sensitive areas such as wetlands where they want to monitor water quality in real time. The city is also using the wireless network for Department of Transportation cameras which monitor a parkway (where there is a drawbridge) for traffic accidents and heavy traffic flows. With wireless cameras streaming live video to DOT offices, they can send emergency vehicles and adjust the timing of the traffic signals to manage the flow of vehicles.
The city has set up a “middle mile” wireless network that connects its fiber network with Wi-Fi access points in parks and areas poorly served by Internet service providers. There is a point of presence (POP) to the fiber network on one side of a large park but it was impossible to use Wi-Fi to connect it to the rest of the network due to the presence of a lot of trees. So they use access points running at lower frequencies.
The city’s use of wireless technology to monitor water quality is compelling. By placing tiny wireless sensors out in the wetlands (which provide real-time information), the city does not have to send a person out every 30 days to do readings, after which it may be too late to fix any environmental damage. Mayor Saffo points out that in the summer, Wilmington gets short but fierce thunderstorms which cause a lot of water mixed with oil to spill out from the roads onto the catch basins and estuaries, and eventually onto the beaches. With real-time wireless monitoring, they can now detect changes in water quality immediately and tell people to stay off the beaches for several hours right after a storm. The cost savings from alleviating water quality problems using this network is about $100,000 per year.
Another application is the ability of the city to turn off the lights in sports fields (ball park, soccer field) shortly after a match. They have installed wireless cameras to see if people are still using the ball park and if not, they turn off the lights remotely (for example, an employee can do this from his home). In the past, the lights would remain on even hours after a match is over. The city expects to save $800,000 per year in energy costs alone.
Additional applications planned for deployment as part of the Smart City trial network include:
- Water Pump Station monitoring and control: reduces energy consumption and costs, increases equipment life and enables faster identification and mitigation of spills;
- Medical telemetry: enables remote monitoring and reporting of biometric measurements for at risk populations; and
- Expanded broadband access for schools: increases student, teacher and administration access to Internet based educational resources.
“Building upon our current information technology investments, TV white spaces will help the County make the most efficient use of our existing resources and infrastructure. It is allowing us to extend video and data connectivity to areas that were once outside of the bounds of current technology due to cost or environmental concerns,” said Jason Thompson, Chairman, New Hanover County. “For example, we are now able to deploy video cameras and WiFi in our parks, which increases both security and enjoyment for our residents and tourists visiting these areas.”
To ensure that the white spaces network does not cause interference with licensed television broadcasts and other protected TV band users, the system operates under the control of Spectrum Bridge’s intelligent TV white spaces database.
This database dynamically assigns non-interfering frequencies to white spaces devices, and adapts in real-time to new TV broadcasts, as well as other protected TV band users operating in the area.