Alpha Omega Wireless Blog

What do you do when you need to provide Internet connectivity for one of the largest live music and film festivals in the world? You build out a wireless backhaul network using point to point microwave!

At the 2011 SXSW (South by Southwest) Film and Music Festival tens of thousands of people from around the world swarmed to Austin, TX to experience the latest in film and see the over 2000 bands that played live at over 200 venues. The SXSW event merges film, music and technology all in one place. Technology is playing an even larger role at SXSW. It was the place that Microsoft launched their new IE9 platform.

Austin was filled with members of the media reporting on the events and who's making news in the film and music industry. Bloggers are found on every corner writing about who's playing and getting signed to large record labels. Live concerts were broadcasted live over the Internet. Bands like the Foo Fighters, Duran Duran, Blue October, Kid Rock, Snoop Dogg, Bob Schneider, Crystal Bowersox, and many others showed up without much warning to perform.

In years past, one of the biggest complaints was the lack of broadband connectivity, that's if you could get connected at all. With so many people in such a concentrated area many of the cellular networks get overloaded and come to a crawl. Add to the fact that there is now a 1 to 1 or even a 2 to 1 ratio of wi-fi enabled devices to people. Laptops, iPhones, iPads, and all the other smartphone devices were present everywhere. This year SXSW wanted to make sure that they could enhance the attendees experience by bringing wireless bandwidth to the people.

SXSW could get a large (GigE) Internet pipe to their corporate office but couldn't get connectivity to the major facilities by the local telecommunication providers. With months of planning At&t, Time Warner, Verizon, etc. failed provide a temporary wireless solution. So they turned to Alpha Omega Wireless to solve the problem. We were able to build out a high bandwidth, point to point wireless backhaul network from their facility to some major venues around Austin. Even though the fiber providers couldn't do it with months of advanced notice the wireless installation of SXSW's wireless broadband was deployed in days.

Because of the bandwidth demand we used full duplex microwave radios, such as SAF Lumina licensed microwave and 24GHz unlicensed wireless ethernet bridges, BridgeWave 60GHz wireless links, and a few unlicensed wireless bridges for specific events. Most venues were able to get 100Mbps full duplex wireless connectivity.

Wireless backhaul used for the core network distribution and last mile wireless used to provide bandwidth to special event venues gave SXSW a lot of flexibility and the ability to provide wi-fi to attendees. Once the event was over the equipment was removed as if it was never there.

Wireless as a Green Technology? Actually it is based on power consumption and impact on the environment. Green technologies are the talk of the town as the world community tries to preserve our planet's natural resources by turning to cheaper and more efficient energy sources. Data and telecommunications are one of the fastest growing industries worldwide. How often do people think about the environmental impact of the broadband infrastructure rapidly being deployed?

For years the USA has relied on fiber infrastructure to provide its broadband backhaul. Fiber deployments require installing fiber cable either by aerial means (strung from pole to pole along a particular route) or by trenching the ground to put fiber in underground conduits. Both impact the environment. Aerial fiber requires a lot of PVC and rubber based jacketing to protect the fiber. These materials are not good for the environment. Aerial fiber also requires poles, either metal or wood, to be placed every 100ft or so. Underground fiber is put into conduits which eventual have a soil impact. Plus the trenching of natural land impacts nature. One must also take into account CO2 emissions that are produced in the construction and deployment of fiber.

Wireless backhaul, such as a point to point wireless Ethernet bridge, can provide data connectivity over 50+ miles. A single communications tower can be a hub site for many fixed wireless backhaul antennas. Existing buildings offer rooftop space that can be used so no new mounting infrastructure needs to be constructed.
Today many point to point wireless Ethernet bridge systems operate at 20W to 35W (-48vDC). Most point to multipoint wireless Ethernet bridge systems can run on POE (802.3af) or POE+ (802.3at). These systems have such a low power draw they can easily be powered by solar or wind generation.

  

Take for example a solar powered repeater site used for a client's video backhaul. On a hill above a reservoir, where there was no local power available, two solar panels provide enough energy to power a point to multipoint wireless system that backhauls multiple PTZ IP cameras located a mile away and a point to point wireless Ethernet bridge to a remote facility 4 miles away. The outdoor wireless system is powered by recyclable batteries that are charges during the day by the solar panels. The systems provides up to 5 days of survivability in the event of the solar system failing.

Installing a solar powered wireless backhaul system is relatively inexpensive, compared to running AC circuits. A quick ROI can be achieved from the savings of equipment shelter leasing costs and monthly power costs. Plus you'll be doing your part to help the environment!

Wireless mesh networks, as a wireless backhaul technology, provide scalability, redundancy and reliability. Fixed wireless mesh can be deployed on existing infrastructure, such as: buildings, traffic signals, and light poles, saving a lot of capital expenditures on the costs of mounting structures. Most outdoor wireless bridge radios that support wireless mesh networking operate in unlicensed wireless bands of 2.4GHz, 5.3GHz, 5.4GHz, 5.8GHz, or the 4.9GHz Public Safety band. There are several really good manufactures of wireless mesh equipment (Firetide, Proxim Wireless, FluidMesh, Azalea Networks, etc.).

In a wireless mesh network, outdoor wireless bridge links are made up of a wireless mesh node that can send and receive wireless backhaul IP traffic. Wireless mesh nodes can function as a router, wireless access point, or a wireless gateway device. Through the relaying process, a packet of wireless data will find its way to its destination, passing through intermediate links providing reliable wireless backhaul communication. If one mesh node can no longer operate, the other mesh nodes can still communicate with each other, directly or through one or more intermediate links. Wireless mesh nodes can communicate with one or more nodes and can determine the best wireless backhaul path to transmit its traffic or perform load balancing on the network.

Wireless mesh networks can be configured in a star topology or be made up of multiple types of configuration topologies such as: point to multipoint wireless backhaul or as a point to point wireless Ethernet bridge. Wireless mesh radios provide the ultimate flexibility from a single device.

Wireless mesh radio platforms have become a popular wireless Ethernet bridge architecture. Wireless mesh first became prevalent in the push for Municipal Wi-Fi applications by the wireless mesh manufactures and by Municipal governments trying to get notarized by offering wireless internet access to their communities. Municipal Wi-Fi was driven mostly by local politicians trying to boost their political clout with very little understanding on the actual outdoor wireless bridge technology. Many of these projects failed because of the lack of having a good business model to offer wireless internet access and in most cases little or no RF engineering was performed (wireless site survey, spectrum analysis, wireless network design, etc.). Making matters worse many manufactures were guilty of over marketing the capabilities of their products (how many wireless mesh nodes that could be deployed before having to have a backhaul to avoid high latency and maintain adequate throughput on the networks) and by not educating their clients on the of potential wireless interference when using unlicensed wireless backhaul.

Many municipal agencies consulted their hardware manufacture, which understand their equipment, but do not have actual experience in deploying outdoor wireless Ethernet bridges, nor should they. They are manufactures not wireless installation services companies. As many Municipal agencies soon found out that the cost was more than anticipated as they were told that to solve any connectivity issues they needed to just add more devices.

The wireless mesh hardware platform was not the issue. The problem was the lack of proper RF planning (performing proper wireless site survey and spectrum analysis), wireless network design, and proper wireless installation. Wireless mesh is a good topology but as with any outdoor wireless backhaul it needs to be done by experienced wireless integrators.

Recently, fixed wireless mesh has found a new niche market to serve. The growth of outdoor IP video surveillance has made wireless mesh a cost effective solution. Mesh, as an outdoor wireless bridge technology, provides the ultimate scalability and flexibility in network design. Wireless video networks can be scaled over time and wireless backhaul using mesh can allow cameras to be placed almost anywhere. Manufactures like Firetide, Proxim, and Fluidmesh were early adopters by optimizing their wireless mesh platform for video backhaul and have done a good job marketing to the IP video marketplace.

Outdoor point to multipoint wireless Ethernet bridge systems are flexible, economical, and easily deployed wireless backhaul solutions for connecting multiple remote sites to a network. Point to multipoint wireless backhaul is an ideal wireless last mile solution for interconnecting campus buildings, remote facilities, security systems, access control systems, IP video surveillance cameras, SCADA PLC's, or WISP applications as a DSL replacement. Point to multipoint wireless can also be used to backhaul wireless mesh networks. Theycan also be used to eliminate telco dependancy or to provide wireless network redundancy.

Point to multipoint wireless Ethernet bridge systems are made up of a Base Station Unit (BSU or AP) that can communicate with multiple Subscriber Units (SU's). Many systems can handle over 100 plus SU's per BSU. In most cases the BSU's provide a sector antenna beam pattern (typical is 60 degree, with some systems allowing external antenna configurations for expanding to 90 and 120 degree sector antennas). Multiple BSU's can be installed to create a 360 degree sector (like a typical cell site configuration). 

Point to multipoint wireless Ethernet bridge systems can operate in the unlicensed wireless spectrum (900MHz, 2.4Ghz, 5.3GHz, 5.4GHz, or 5.8GHz), the 3.65GHz WiMax spectrum,  or in the 4.9GHz public safety band. There are propriatery point to multipoint wireless backhaul systems operated by various telecommunication providers that operate in the lincensed microwave wireless spectrums.

Point to multipoint wireless backhauls is generally used where bandwidth requirements are generally low, such as a DSL or T1 repalcement. Recently though  many point to multipoint wireless systems have taken advantage of the Wi-Fi 802.11n chip sets and can now provide wireless bandwidth up to 300Mbps aggregate throughput. Note: the actual throughput at any given SU is determined by the number of SU's connected in the system and the network configuration.

Some of the better point to multipoint wireless systems use OFDM (Orthogonal Frequency Division Multiplexing) to provide better near and non line of sight ("NLOS") connectivity. The newer 802.11n chip set systems also take advantage of multipathing by incorporating MIMO (2x2 or 3x3) to give even better NLOS capability and higher bandwidth. The range of a point to multipoint wireless backhaul can extend as far as 10 miles with clear line of sight ("LOS"), by using high gain directional antennas connected to the SU's. The optimum performance though of most point to multipoint wireless is in the 1 to 2 mile max range. NLOS applications need to be closer to the BSU / AP in order to have adequate system gain. 

There are a lot of manufactures that offer point to multipoint wireless Ethernet bridges. Some manufactures have been in the point to multipoint wireless arena for many years. Proxim with their Tsunami MP.11 series (5054-R which is a tri-band 5.3GHz, 5.4GHz, or 5.8GHz system, MP.16  that is a 3.3GHz, 3.5GHz, or 3.65GHz licensed WiMax system, and their newer high bandwidth MP8100 series), Motorola with their Canopy wireless (their newest is their Canopy 400 series that operates in the 5.4Ghz and the PtMP320 WiMax), and others such as: Alvarion, Firetide, Trango, Solectek and BelAir. Some of the newer players include FluidMesh (which specializes in wireless video backhaul and wireless mesh), Ubiquiti,and InscapeData.

When designing a point to multipoint wireless Ethernet bridge system it is highly recommended to perform a wireless site survey and a spectrum analysis. All systems regardless of how good they are have their limitations. The biggest source of failure we come across is unrealistic expectations of performance. Any organization thinking of deploying a point to multipoint wireless system should consult a professional wireless integration company that has a lot of experience designing and performing outdoor wireless installation. 

The video market is merging from traditional analog cctv to IP based camera systems. There are many advantages to IP based camera systems over traditional analog cctv. First, it's more cost effective to deploy IP cameras on existing IT infrastructure. Second, there are fewer points of failures (e.g. encoders, transceivers, decoders, multiplexers, analog monitors, etc.). Third, IP based cameras have more functionality. Fourth, it's easier to centralize and manage multiple sites. Fifth, better storage and achieving solutions. Finally it's easier for an IT department to support (they don't need special tools and training on coax. They already know how to work with CAT-5e).

The drawbacks are the need for greater bandwidth across the IT network and the limitation of CAT-5e to 100m (unless you are using Ethernet extenders). The solution to both problems can easily be solved by the use of wireless networks. With wireless IP video cameras can be deployed virtually anywhere. Bandwidth also becomes a non issue as a wireless network can be scaled easily.

   

Putting video across wireless can be tricky. To optimize video streaming over wireless, whether we are talking about point-to-point, point-to-multipoint, or mesh networks, some experience and knowledge is needed. First is selecting the right wireless equipment. Many wireless manufactures offer QOS and VLAN tagging capabilities which make for ideal video surveillance configurations, as we typically want our video network to be on a separate subnet than our traditional data and voice traffic.

If you know what you are doing and have a solid background in wireless and IP networks it's easily done. The problem we see most of the time is the company doing the deployment is lacking in one of the areas. Too often we see installations that have issues because the installer just throw up a bunch of mesh equipment, using omni-directional antennas, hoping for a plug and play situation. What happens is a lot of self interference (along with outside interference) and too much latency on the network. Even though many hardware manufactures would like you to believe their equipment is plug-n-play that's not how it works in the real world. Someone that is well trained in wireless networks should be used to deploy any such networks so they can be optimized and configured properly.

Understanding IP video is another area we see issues. Many traditional analog cctv vendors just don't understand IP networks well enough. If your vendor doesn't understand QOS and VLAN technology they probably don't have enough experience to deploy a wireless video solution.

Just like wireless hardware not all being the same nor is the IP cameras. Some work well over wireless and some have issues. Choosing the right camera is important. It's best to make sure before purchasing and deploying any wireless video solution that you have (or at least get confirmation) that the matching of a wireless manufacture's equipment and a particular IP camera system work well together. My company, Alpha Omega Wireless, deploys a lot of IP video surveillance cameras over wireless networks. We'll be performing various test of different video cameras on various wireless equipment and will be posting regularly the results. Stay tuned!