The rule states: “U-NII devices already play an important role in meeting public demand for wireless broadband service, particularly wireless local area networking and broadband access. This foundation, coupled with increasing demand for wireless broadband applications and new Wi-Fi technology, signals a bright future for unlicensed operations in the 5GHz band. To meet continuing demand, in this first rule and order, we are taking a number of actions to increase the utility of the 555MHz of the 5GHz band already available for U-NII operations, while protecting incumbent users from harmful interference.”
“This new rule changes the 5.150-5.250GHz band to be available for outdoor use, the transmission power level is increased to 1W and the EIRP [Effective Isotropic Radiated Power] is increased,” Nelson explains. “These changes will result in easier adoption and integration of all available spectrums to devices.”
Wireless Network Topology Overview
By Jake Shehan
There are several different network topologies to consider for video surveillance applications depending on the type of installation method. For outdoor deployments, it comes down to what the network is being used for and the environment. If the purpose of the network is to simply transfer video over the air, there are three topology options:
Point-to-Point (PtP): This is simply accomplished by using a wireless bridge to transmit from one set place to another. Typically, this is the easiest option as long as you have line of sight between the two sides of your wireless bridge.
Point-to-Multipoint (PtMP): Similar to PtP in that you need line of sight between the two radios, in this scenario you have several remote locations transmitting and receiving back to a single location, sometimes referred to as a base station.
Mesh: A mesh network is by far the most difficult topology to deploy and manage on the list. For a successful installation, a very good site survey is a must. These are most easily described as a web of radios deployed which all speak to each other to transmit the data from one end of the network to the other. The biggest consideration in mesh is to limit the number of radios you are meshing between (referred to as a hop) as much as possible because with each hop you lose approximately 50% of the throughput you began with.
Jake Shehan is Director of Merchandising for ScanSource.
Pesky Snafus Integrators Face
Systems integrators that are looking to capitalize on new opportunities to install wireless video for perimeter protection often face challenges related to camera placement and the need for systems to conform with a customer’s existing security processes.
“For networking experts, installing cameras on the IP backbone is easy compared to the challenge of locating cameras for optimum video coverage and security benefit,” Tynan says.
As the unique needs of a particular customer may require installing cameras beyond the reach of the existing power and network infrastructure, integrators need to look beyond traditional surveillance devices to help end users gain the level of surveillance coverage required for external security applications.
“We as developers of these technologies must be prepared to provide the tools to succeed with wireless design,” Tynan continues. “Site surveys to determine line of sight, stray RF, distance to target and Google Earth maps are all tools used to develop a bill of materials that will lead to a predictable installation event.”
The biggest struggle with wireless deployments integrators face will often arise from not doing a proper site survey of the installation site, says Jake Shehan, director of merchandising for Greenville, S.C.-based ScanSource, a wholesale products distributor and value-added services provider.
“If integrators do not have the tools and expertise to do this on their own,” Shehan says, “it is better to bring in an expert upfront before the installation than to have to bring someone in to try to solve what is wrong with a system that’s already deployed and not performing.”
Due to the very nature of wireless being unseen, the technology itself can seem mysterious to end users and integrators alike, Nelson says. Understanding what is in the air can be half the battle to successfully designing and deploying a wireless solution. There are a number of tools, from a laptop to a sophisticated spectrum analyzer, that can be used to see and detect what is in a site’s wireless environment. Mitigating interference using frequency, channelization, antenna location and directional antennas can all help to insure a robust and reliably performing wireless security network.
“Knowing how many Wi-Fi access points and devices are in the same general area of deployment can be critical to understand where and how to deploy your wireless security system,” Nelson says. “Other RF emitting devices can impact your signal quality and reliability.”
Also common, installing security contractors will start down the wireless path and forget about electrical power. Wireless systems can carry video and data wirelessly, but the cameras and wireless networking devices still require power.
“Wireless power today only comes in the form of solar, wind and batteries. Make sure your wireless networking configuration has a power plan,” Nelson advises. “There are some great wireless devices that now support power over Ethernet [IEEE 802.3af-2003 and IEEE 802.3at-2009].”
The IEEE 802.3at standard supports up to 25W of power, which is adequate to support most 802.3at standard PoE cameras. Using PoE can help to minimize power cabling and make for a cleaner installation.
No Need for Costly Trenching
As wireless technology continually improves, total cost of ownership (TCO) for using wireless networks for video surveillance is becoming increasingly attractive when compared to the pricier alternative of trenching cable.
Here is a scenario described by Cosimo Malesci, co-founder and vice president of sales and marketing for Buffalo Grove, Ill.-based Fluidmesh Networks, to illustrate the potential cost savings of a wireless system. Imagine having a new warehouse located one mile away from your headquarters, and having to provide video surveillance of the warehouse back to the head office. You could decide to dig and use a cabled backhaul, although associated costs are exorbitant compared to a simple point-to-point wireless backhaul via radios.
“You could also use a 3G/4G system but it’s less reliable,” Malesci says. “You will never have a dedicated and reliable broadband for continuous streaming, and you have to pay the bill every month to the carrier!”
Compared to the rest of an enterprise surveillance solution, the part of the system covering the outside perimeter is the most expensive on a cost-per-camera basis.
“In terms of sustainability and cost, longer cable runs translate into more materials being used, and trenching through concrete, aggregate or asphalt negatively impacts drainage and erosion,” Tynan says. “Longer term, corrosion can weaken or terminate signal strength altogether, and even rodents have been known to develop a taste for various flavors of cabling.”
Moreover, the fuel consumption of (and emissions from) a backhoe used for trenching impacts the environment, and adds significant time and costs to an installation. Remote sites and associated return trips exacerbate installation costs. Also, extra time and resources are required for permitting, including awaiting approvals.
In terms of technology costs, megapixel and/or premium-priced pan/tilt/zoom (p/t/z) cameras mounted on a building to view distant areas are more expensive than standard resolution cameras mounted nearer the actual area at risk. Additional costs include the electricity used per camera, electricity used by heater/blowers and the cost of powering incremental lighting.
Wireless surveillance systems help reduce both installation (capital) as well as operating (long-term power and transmission) costs. Wireless cameras can be deployed in a matter of hours to reduce installation times by up to 90% over traditional video systems, saving users tens of thousands of dollars. For example, the cost for trenching is typically $50 to $100 per foot. For concrete or asphalt, costs increase considerably, doubling to $100 to $200 per foot.
“Less-disruptive wireless installations not only reduce cost,” Tynan says, “but eliminate most of the sustainability impact, and lower power consumption over the life of the system promotes ongoing sustainability.”
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