Put Wireless to Work for Your Video Jobs
During the past decade, there have been major advances in technology that allow wireless solutions to become a viable element in video surveillance systems. These solutions have transformed the video surveillance market and opened a new world of opportunities for security integrators.
In the early stages of wireless video deployments, systems were typically limited to point-to-point transmissions; limited bandwidth and transmission of analog signals proved to be the only available option. Frequency Modulation (FM) was primarily used and resulted in average- to poor-quality video. The low-quality video was subject to real-time interference such as shadowing and other interference-induced display issues, many of which rendered video unusable.
The advent of digital encoding has revolutionized the video surveillance marketplace. As embedded processors are becoming more powerful, the amount of analog video data that can be transformed and transmitted using standard Ethernet networks will continue to increase. This bodes well for wireless video deployments since the digitally encoded video is not only transformed into a digital stream (reducing the risk of corruption), but it is also compressed to allow more data to be transmitted across the wireless network.
By training, planning and self-educating, integrators providing wireless expertise are in an excellent position to give end users a robust, functioning system that incorporates wireless technology.
Sticking to Standards
Wireless Ethernet standards (802.11a/g) and the introduction of mesh networks have also simplified 
the deployment of wireless surveillance systems by providing a simple means of communicating video data to recording software or other hardware connected to the wired portion of an Ethernet network.
Adding to this more robust and efficient modulation scheme is orthogonal frequency division multiplexing (OFDM), which helps increase the amount of bandwidth on a conventional wireless Ethernet network. This increase in available throughput provides a launching pad for more viable, sustainable wireless video surveillance systems.
As wireless standards continue to evolve with the recent introductions of 802.11n, multiple-input, multiple-output (MIMO), channel combining and Wi-Max (802.16), the available bandwidth to transport video data wirelessly has increased to a point where it rivals wired 100BaseT Ethernet’s throughput capabilities. Further advances in technology allow users the ability to access real-time video to display or record on a device through a mobile client.
Many products on the market take advantage of high throughput capabilities provided by 802.11 standards. These products also provide integrated video encoding technology within the same enclosure and use codecs designed specifically for the video surveillance environment. Combining these technologies helps simplify deployment and reduce the overall cost of the end user’s system.
Benefits of Planning in Advance
All these advances in video encoding and wireless technologies are wasted if the systems are not planned and deployed properly. Understanding the science behind the wireless technology is critical when planning and deploying a system.
You don’t need to know how to implement Advanced Encryption Standard (AES) or set up a virtual local area network (VLAN) across a wireless link. Instead, learn and understand how the vibrations of electrons in one antenna function so as to make electrons in another antenna vibrate, thus providing data to the device attached to it. This may sound a bit abstract, but grasping some key concepts of radio wave propagation, understanding the limitations of these types of systems and adding some common sense can make it easier than it might seem.
The most important aspect of a wireless video deployment is obtaining stable wireless links. Unlike a wireless deployment for an office or a mesh deployment provided solely for the transmission of data, a real-time video surveillance solution cannot wait as long as a Web browser or E-mail application. If too much time passes and the wireless data is not retrieved, everything begins to degrade and the video stream becomes unusable.
A stable wireless link provides a constant level of throughput in order for the video stream to pass, which is critical to proper viewing and recording of video arriving from the field. Another important aspect is the proper use of the video encoding technology at the remote end of the wireless system. Full motion, high-resolution video for all cameras in a wireless system may sound viable due to the increase in 
available bandwidth. This idea needs to be tempered by the reality that the bandwidth stated by wireless manufacturers is for best-case deployments operating at the maximum channel data rate and free of interference from like devices on the same or adjacent channels.
In order to visualize a best-case scenario, picture a container yard. This situation proves difficult to deploy wireless solutions when you consider the changes that occur daily due to weather constraints and other forces of the environment. Consider that your available throughput is small due to the attenuation of the radio signal, distance and interference. The proper encoder settings prohibiting video data streams should not exceed the amount of bandwidth available.
If you enjoyed this article and want to receive more valuable industry content like this, click here to sign up for our FREE digital newsletters!
Related Content
Security Is Our Business, Too
For professionals who recommend, buy and install all types of electronic security equipment, a free subscription to Commercial Integrator + Security Sales & Integration is like having a consultant on call. You’ll find an ideal balance of technology and business coverage, with installation tips and techniques for products and updates on how to add to your bottom line.
A FREE subscription to the top resource for security and integration industry will prove to be invaluable.
