Wireless Home Monitoring is part RF technology, part artistry, and part magic. How technologically spoiled we’ve become is apparent when we don’t realize that having a cellular teleconference among three people, each driving down an expressway on a different continent, is nothing short of magic. Just ask anyone who worked on the technology to make it all happen. When working with wireless communications, you’re entering the RF world of waveforms once again, but these waveforms, open to the outside world, can succumb to a number of problems, including interference, noise, weather, and vibrations, not to mention the limitations of the chosen software and hardware. You may see it as a “simple” solution when there is no wired alternative, but it’s not an “easy” solution. However, when it works, it is indeed magic.
The radio frequency spectrum is divided into small chunks for a huge number of applications, from AM and FM radio, television, and cellular networks to walkie-talkies, satellite communications, military applications, and even to send and receive signals into outer space, hoping for a reply. Transmitters and receivers are modulated to “hear” only the specific programmed frequency, but, depending on the power and frequency, there may be “bleeding,” which can cause interference. Moreover, there are software and hardware limitations and programmability issues. It’s not a simple task to create the magic RF box, especially for the implementation of a video network using the available standards. It would be much easier if there were a standard, exclusive frequency set aside specifically for video networking (as with Wireless GPS Tracker For Car ), but RF shares bandwidth and channels with email, Internet access, and backhaul connections between offices and buildings.
Thus, we see scenarios where five network television stations are broadcasting in urban areas, each with its own exclusive piece of the spectrum, while there may be a hundred individuals trying to share a minute portion of the unlicensed spectrum for wireless networking Wireless does not mean “without wires” unless the design specifications require a closed wireless local area network (WLAN) between wireless client workstations or laptops and the individual Rear View Mirror Camera all linked via a wireless access point (AP). In the majority of cases, at some point you’ll be connected to a wired backhaul if you want remote access (from anywhere else) via the Internet. As discussed in the previous chapter, many resources, such as printers, file servers, storage, and the Internet, are shared within a LAN, so without wires you limit accessibility to the system. If you are using digital video encoders and IP cameras, you also need to consider the Ethernet link between the actual encoder and/or IP camera and the wireless radio as well as the power. Wireless networked video provides another option for data transmission but cannot replace the basic need for power, so keep in mind that if there is a new conduit design for power, the cost is not much more to have parallel conduit runs, one for power and the other for data.
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