The battle between the Consumer Electronics Association, the NAB, the FCC and Congress appears to be in a relative frenzy and due to climax sometime soon. It now appears compromise in the debt ceiling legislation will make the incentive TV spectrum auction legislation voluntary. It's not a done deal yet, it was a long week and next week promises to be longer for all involved. In case you missed it, the NAB put up a website in response to the CEA website discussed in the last "Transition to Digital." The NAB website is at www.thefutureoftv.org. Game on.
While those in charge at the nation's capitol toss around megacycles like money, we at "Transition to Digital" will rack our focus back to solving today's problems today.
It's those darned hams again
This tutorial will examine some uses of RF spectrum in the so-called 2.5GHz and 5GHz bands. The 802.11 Wi-Fi concept began with a 1985 FCC ruling that released the industrial, scientific and medical (ISM) radio bands for unlicensed use. The ISM bands were originallyreserved internationally for industrial, scientific and medical RF applications other than communications such as microwave ovens.
Interestingly, the frequencies of what became channels one through six of the 802.11b/g Wi-Fi band overlap the 2.4GHz ham radio band. Thank the hams for their pioneering work at these frequencies, and know that all but they who use these frequencies are limited to a range-restricting 100mW power output.
Licensed radio amateurs can operate 802.11b/g devices under Part 97 of the FCC Rules and Regulations at much higher power levels. Because 802.11b uses direct sequence spread spectrum, hams radio operators can only boost the power to 10W. But the OFDM modulation used by 801.11a and 801.11g isn't classified as spread spectrum, so hams are allowed a peak output up to a searing 1500W. It's ham radio, so it can't contain commercial content or encryption, but it does offer some interesting potential to experimenters. Among hams, the 2400-2450MHz band is known as the "Hinternet." If you're having strange interference problem on channels one through six on your Wi-Fi router, it's not likely, but a local ham just might be your problem.
Among other familiar devices operating in these bands are several low-cost unlicensed 100mW wireless analog video and digital data transmission systems.
21st century duct tape?
Wi-Fi is starting to compete with duct tape for the greatest number of divergent uses around a television facility and remote locations. Today's industry climate requires modern television facilities to be Wi-Fi friendly. It isn't unusual to find cellular base stations, access points and bridges providing wall-to-wall Wi-Fi coverage across a TV station's IP infrastructure. Everyone likes the mobility of laptops, tablets and iPads on a Wi-Fi network. Not everyone is aware of some other useful stand-alone gadgets that integrate real-time operating systems with built-in Wi-Fi communications to provide a simple way for a portable serial device to wirelessly reside on a network. A Wi-Fi webcam is a good example.
One of the handiest stand-alone Wi-Fi webcam devices is the Wi-Fi security camera. There are several manufacturers offering a number of Wi-Fi security-style cameras. What all these cameras have in common is the ability to log onto a Wi-Fi system and act as a stand-alone streaming video server. Typically, they are addressable as a local 192.xxx network device in a Web browser, and easily accessed on the Internet or by Web-enabled smart phone.
Some of us are blessed with static IP addresses and plenty of ports. Others of us are, for some reason or another, seemingly stuck with a dynamic IP address both now and in the foreseeable future. When I began researching Wi-Fi webcams, one of the first questions that came to mind was how to find my camera on the Internet when my DSL IP address was dynamic.
Fortunately, there are at least a couple of websites such as www.no-ip.com and www.dyndns.com that provide a solution. Both these sites offer dynamic DNS service (DDNS). It provides the capability for a networked device using IP to notify a Domain Name System (DNS) name server to change, in real time, the active DNS configuration such as a new IP address.
Small users who only need one or two addresses can use the service for free. The service uses your Internet connection and router to redirect Internet inquiries to a specific named host, such as a webcam you named "Bob" to a specific IP address in your local network infrastructure such as 192.168.1.149. When an outside user wants to see the camera "Bob", it can be found on the outside user's Internet browser by calling up the name address such as http://bob.dyndns.tv. DynDNS or no-ip.com does the rest.
The beauty of a Wi-Fi webcam system, as opposed to using a wired webcam with Symantec pcAnywhere for instance, is that it doesn't require a computer at the front end, nor does it require any special software or gadgetry at the receiving end.
DDNS opens a world of opportunities for instances that were more complicated or cost more to resolve than they were worth. One of the most obvious opportunities is security. A wireless webcam needs no more than an AC outlet and a place to sit or hang. It can watch people, equipment or property. It can graphically track the progress of projects. Sometimes, it can reach out and tell you when things are amiss.
Like a steel trap
Most security-style Wi-Fi webcams refer to motion detection as an alarm. Many of these webcams have the ability to record, based on motion or sound with adjustable trigger sensitivities, to a local network drive or to an on-board internal storage card. Some Wi-Fi webcams take it to the next level with an alarm feature that can alert your Web-enabled cell phone with a picture or series of pictures when it detects motion, or in some cases, hears an unusual sound. Some cameras will upload picture files to a FTP server. Some will send you an e-mail. Some offer remote pan, tilt and zoom. Isn't it good to know that a potentially slippery situation can be securely and dependably watched and documented automatically for you 24/7? You didn't even have to run Cat 5, find a new port on the router or resurrect a retired computer for a USB webcam.
Does your facility have a few permanently installed security cameras and perhaps a multichannel DVR with several days' storage? Simple systems like this are typical in many normal security monitoring situations such as outside doors and parking lots. On the other hand, as we well know, TV stations aren't always normal.
There are many one-time events or possibilities of events inside and outside TV facilities where it would be helpful from an engineering and management perspective to have the ability to easily temporarily monitor activities and equipment with smart Wi-Fi webcams. Sometimes, it might also useful to share this capability with others such as your GM, which is easy to do with a Wi-Fi webcam. Once you start using highly mobile Wi-Fi webcams to help solve problems and answer questions, you might wonder how you functioned without them.
Most full-featured Wi-Fi webcams typically start at about $200.
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