CCTV Digital Video Recorder

Wireless Security Cameras

So you want to install a wireless camera system? Depending on your application, installing a wireless video system can be simple or very complex. If you have the right knowledge, equipment and settings, wireless video transmission can open up a world of possibilities and opportunities.

Wireless video; It might sound easier than installing all that cable, but depending on your application, the learning curve can be steep. You may need expertise in RF engineering, a degree in regulatory law, and an FCC license to enjoy all the benefits.

Wireless video systems can range widely in cost, capabilities and effectiveness and transmission distances can vary from 50 feet to over 5 miles depending on the frequency and the rated power output. A standard system consists of a transmitter, a receiver, an antenna and some power supplies.

For the best results and the longest range, most wireless video transmission systems require a clear line of site between the transmitter and the receiver to operate consistently. Wireless video signals do not penetrate very well through glass, walls, concrete, trees, steel or other obstructions.

2.4 GHz Analog Wireless Cameras

Most consumer grade wireless camera systems designed for home use utilize analog video transmission in the 2.4GHz frequency band systems are usually simplex and they only transmit video in one direction.

Currently, the entire 2.4 GHZ bandwidth allocated for consumer use is from 2,412 MHz to 2,462 MHz. As per the FCC standards, there are 11 possible channels which are 22 MHz wide with a 5 MHz spacing interval between each.

In order to allow multiple wireless video streams on the same system, consumer grade 2.4 GHz analog video transmitters such as a wireless baby monitor or a front door camera require fixed frequency, non-overlapping channels to reduce interference.

In the 2.4 GHz analog frequency range there are only 4 non-overlapping channels available which limits the system to 4 cameras, each of which must be tuned to a separate pre-defined frequency. Each of the 4 channels is capable of transmitting about 11 mega-bits per second of data (Mbps).

Because the analog 2.4 GHz camera systems are on fixed frequencies, they are especially susceptible to interference from cordless telephones, microwave ovens, local television broadcasts, computer monitors, power supplies or wireless LAN/WANs which can all share the same frequencies.

A typical transmission range for an analog 2.4 GHz wireless video link is about 300 to 500 feet when installed outdoors with a clear line of site and little interference from outside sources. Analog video signals do not penetrate walls, ceilings or floors very well so the relative transmission distance is greatly reduced when installed in the typical office or home with some lower end analog systems typically providing about 50 feet or less.

Since these wireless cameras are transmitted on a fixed, un-secured open frequency, the signal is easily intercepted and can be seen by anyone with a 2.4 GHz 4-channel receiver. A voyeur or a burglar could simply drive around a neighborhood with a receiver and see inside your home. If you have one of these systems installed, perhaps a burglar is watching you right now.

2.4 GHz Digital Wireless Ethernet Cameras

In 1997, the Institute of Electrical and Electronics Engineers (IEEE) created the first Wireless Local Area Network (WLAN) standard which was named 802.11. The original 802.11 utilized the 2.4 GHz frequency to allow reliable transmission of 2-Mbps of bandwidth. In 1999, the standard was upgraded to 802.11b which supports up to 11 Mega-Bits per Second (Mbps) which was comparable to traditional Ethernet connectivity speeds.

The 802.11 protocol works by sub-dividing the entire 2.4 GHz frequency into channels and switching between them during transmissions. As the signal is sent, it sends a packet of data at one frequency and then hops to the next channel and sends another packet and so on, until the entire data package is sent.

In 2003, WLAN products began supporting a new 2.4 GHz wireless standard called 802.11g which supports a bandwidth of 108 Mbps of data. The days of cost effective, reliable and secure wireless video transmission have finally arrived.

The added features and benefits of using internet protocol cameras and 802.11g for wireless video transmission in a security application are many.

The 802.11g protocol utilizes digital bi-directional signals which support the use of pan/tilt/zoom functions and presets found in many newer cameras. The digital signal used is duplex (bi-directional) as opposed to the simplex (one-way) binary signal used in analog type systems.

Because 802.11g utilizes the entire 2.4 GHz frequency spectrum, interference is greatly reduced and longer transmission ranges can be expected. If an area of the frequency is noisy then the transmitter/receivers will adapt the signal by sending smaller packets in the noisy affected area and larger packets in the non-effected areas of the frequency. A wireless IP video system will offer almost the same performance as a professional grade wired system with a reliable transmission range of 150-200 feet.

If the camera is to be located further than 200 feet, directional antennas are available which can increase the distance to 600 or more feet. If a greater distance than 600 feet is required, point to point, long range directional type systems can increase the distance to several miles.

In addition to standard 64/128-bit WEP Security, 802.11g protocol allows data packets to be encrypted using a 40-bit RCA key. When considered in conjunction with the inherent security built into DSSS spread spectrum technology, the wireless camera data signals are at least as secure as data traveling over a wired network.

The 802.11g protocol can support a much larger number of wireless cameras by using a medium access control or MAC layer called CSMA/CA or Carrier Sense Multiple Access/Collision Avoidance. The collision avoidance in 802.11g supports the use of CTS/RTS signals (clear to send/ready to send) which tell each camera on the system when it is O.K. to begin transmitting or receiving data thereby avoiding interference.

Any hardwired IP Camera that is installed on your intranet or internet that is using the same CODEC (Coding & Decoding) algorithm can be integrated into the same software viewing and recording system.

An IP addressable camera system can be viewed or recorded from a properly equipped computer from any location in the world. This can allow you the freedom to move anywhere on the planet while still keeping track of your assets. In addition, if you ever decide to move your head end recording equipment to a different location, you simply pick it up and move it. No wires to re-route.

One thing to remember when deploying a multi-camera wireless IP based video system is that processing multiple streaming video signals places a substantial work load on a computers CPU.

Hard Wired systems have video capture cards which are installed in the PC/DVR. These cards take up to half of the work load off the computers CPU. Because wireless IP video systems do not have the help of these capture boards, the computers CPU must handle 100% of the processing workload.

What this means is that as you add cameras to a wireless system the total frame rate or the total images per second which can be viewed and recorded will decline due to the increased workload.

Some people shy away from IP and network security solutions because they appear to be complicated and difficult to set up. The fact is the initial set up does require some expertise and knowledge but the operation and day to day use of the systems are no different than using any other PC based security camera system. The required computer skills are minimal. If a person can check email, use a word processing program or load and play any type of game on a PC they most likely possess the skills needed to use and manage a PC based system.

Wireless Mesh Network Multipoint Wireless

If your requirements are for multiple wireless security cameras spread out over a large area such as an industrial plant or a port facility with little or communications infrastructure, a traditional wireless network would not have the required range or provide the level of quality required to operate fluidly. In this application, you might want to consider installing a mesh wireless video network which presents huge advantages in reliability and flexibility.

Unlike traditional point to point wireless Ethernet based wireless systems, a mesh network combines a series of intelligent routers that can forward data and video packets in real time through the optimal path by routing around physical obstacles and sources of interference. In a wireless mesh network, every router has the ability to forward video packets coming from other routers as well as any data packets coming directly from the cameras connected to it.

With the ability to operate in different frequencies from 2.4 to 5.8 GHz, a mesh network can select the optimal frequency to take advantage of fluctuations in network traffic and channel quality to increase the reliability of the network. Every video stream has multiple paths available to reach the base stations and the network forwards the video through the optimal path at any point in time to increase the reliability.

Highly secure VPN, SSL and HTTPS and AES 128 bit encryption can be implemented at the link level to guarantee the security and authenticity of the video streams without any loss of performance.

Mesh network technology is fully compatible with wireless IP based security cameras, video servers and other Ethernet based devices so you can utilize any brand or style of wireless internet camera that fits the application. Each mesh router can detect the type of video streams and the transport protocol and optimize the transmission type and priority to take advantage of available bandwidth.

High Power Point To Point 5.8 GHz Microwave

If you need to transmit video, audio and data between locations up to 12 miles or more apart and you can establish a clear line of site, then a point to point microwave video system just might be the best solution for you.

In much the same way that a flashlight projects a beam of light from one point to another, microwaves can be transmitted along a straight, unobstructed line from a transmitter to a receiver. In the process the microwave beam can carry audio and video information.

A clear transmission path must exist between the two link nodes of any microwave radio link. Any solid obstructions, or even heavy rain, sleet, or snow, can degrade or completely obliterate the microwave video signal. Furthermore, as the radio wave disperses as it moves away from the source, there must be additional clearance over any obstructions to prevent attenuation of the transmitted signal. This additional clearance, known as the Fresnel zone, differs for the frequency band of the radio path, where higher frequency translates into a smaller clearance requirement.

Microwave signals have the capability of providing sub-carriers for transmitting audio or data information. These sub-carrier interfaces include audio/FSK, RS-232, RS-422, and most all camera control system interfaces. These sub-carriers may be used for two-way audio, camera control, or video switching. This two-way data transmission also makes it possible to remotely operate card readers, gates, and turnstiles.

In broadcast television, microwaves were originally only used in for coast-to-coast network television and for studio-to-transmitter links. However, as remote broadcasts became more popular, TV stations saw an advantage in having field production trucks equipped with microwave dishes so that news stories, athletic events, parades, civic meetings, etc., could be covered live. The field trucks point their dishes at the receiver which is typically located on a tall building and then transmit the live video and audio feeds to the production room.

Although normal microwave signals go in a straight line, it is possible to use Omni-directional microwave transmitters to send audio and video signals over a sizeable area such as a race track or a sports stadium. This is how NASCAR provides you with all those in car camera feeds and how they transmit live video from motorcycles during the Olympics or the Tour De France.

Most of the high power microwave video transmission systems will require an FCC license to operate. The FCC must conduct a frequency search before they will issue a license, but they are fairly easy to obtain. No matter what frequency you plan on using, if you are installing a high powered microwave video transmitter, you should contact the FCC to secure the appropriate licensing. The frequency search allows each system to be individually tuned to a specific assigned frequency to ensure interference free operation and provide a reliable communication link.

In recent years, the FCC has created some lower powered pre-licensed microwave transmission channels specifically dedicated to video surveillance that do not require a frequency search and an FCC license to operate. These systems can transmit real time high quality video for 2 miles or more.

Wireless Camera Installation Skill Level

Analog Wireless Cameras :Just about anyone can install and configure a wireless 2.4 GHz analog video camera system. These are simply plug and play units with little or no adjustments available. If the camera has a bad picture, the only thing you can really try is to move the camera or the receiver until the signal clears up. If you are installing a camera to watch your driveway and you’re viewing it in your kitchen, then an analog wireless camera just might be your best solution.

Wireless Ethernet Camera :Some people shy away from IP and network security solutions because they appear to be complicated and difficult to set up. The fact is the initial set up does require some expertise and knowledge but the operation and day to day use of the systems are no different than using any other PC based security camera system. If you have good computer and networking skills and a wireless network already installed, then a wireless internet camera system could easily work for you.

Mesh Wireless Network :Installing a wireless mesh network video system is not for the inexperienced or novice IT guy. Hire a professional security company with high level networking experience. Many factors including site surveys can make this a very expensive proposition, but certain high security applications can justify the expenditure.

High Powered Point to Point Microwave :As with a mesh network, I would not suggest installing your own microwave system without a background in broadcasting, high end networking or security system applications. With a single link costing thousands of dollars; it is best to enlist the help of professionals who have previous experience with microwave systems.

Wireless Cameras Operators Skill Level

Once it is installed, tested and configured, the operation and day to day use of any wireless security camera system is no different than operating any other camera security system. The required computer skills are minimal. If a person can check email, use a word processing program or load and play any type of game on a PC they most likely possess the skills needed to use and manage a wireless video systems.

Wireless Camera System Design Considerations

The design of a Wireless IP Security Camera System is basically the same as it would be in designing any other video surveillance system. The steps are:

• Identify the areas which you require video security.
• Choose the correct type of camera to cover each area of concern and verify that there is power at each location for the security camera. Camera locations should be free from metals, concrete, computer monitors or other electronic devices which could cause interference.
• Identify the location of your head end computer or digital video recorder.
• Decide which type of wireless video transmission system you would like to implement based on the wireless range for your application. Remember, if you are considering a mesh network or a point to point microwave system, we highly recommend that you consult a professional.
• Locate the best location for your receiver. Make sure that there is power for the receiver and that the location is free from large metal objects, concrete, computer monitors or other electronic devices which could cause interference and reduce the range.
• Install and configure your wireless network.
• Install and configure your wireless cameras.

Have questions about your application, the professionals here at Security-Kits.com are always available to help you with the engineering and design of your wireless video surveillance system. Please feel free to call one of our experts at 1-888-370-4287 from 8am to 5pm MST Monday through Friday.