Over-the-air (OTA) HDTV becomes increasingly more popular. For a person who is utilized to noisy analog TV pictures, it's challenging to believe how incredible a top quality of HDTV broadcasts may be. In fact, HDTV channels received over the air free of charge frequently have greater high quality than the same channels received via a paid satellite HDTV subscription. All you'll want to enjoy OTA HDTV is really a HD television with a built-in HDTV tuner and an HDTV antenna.

Huh? Which type of antenna?! In the event you have Ph.D in Electrical Engineering and have never heard about the antenna sort known as "HDTV antenna", it's not since you were a bad student. HDTV antenna has nothing to do with physics and engineering. It was invented in advertising departments. Advertising discovered an efficient trick to boost TV antenna sales. HDTV is really a hot thing nowadays. Call essentially the same device HDTV antenna, and it sells better. It makes folks to believe they ought to acquire an HDTV model or HDTV optimized antenna to watch HDTV broadcasts. This is quite far from truth.

HDTV antenna hype developed a large misconception with regard to TV antennas utilized for HDTV reception. This article is an attempt to clarify this issue.

Do you know what a regular antenna is? Antenna is a piece of metal designed to resonate at a particular frequency and to be responsive over a specific range of frequencies. TV antennas are created to work either in the range of Ultra High Frequencies (UHF), Extremely High Frequencies (VHF) or both. Any station transmitting within the VHF/UHF frequency bands, could be picked up by a VHF/UHF antenna and transferred to the TV set.

All television broadcasts, digital and analog, are in the VHF and UHF bands. Over 90% of the HDTV broadcasts are within the UHF, and much less than 10% within the VHF band. What is crucial from the antenna perspective is that HDTV falls inside the bandwidth of a normal VHF/UHF antenna. Not HDTV antenna, not HDTV optimized antenna, just a regular normal TV antenna. What makes a signal to be HD is its content, the way a signal is modulated, and not the carrier frequency it's transmitted on. On the contrary, the antenna knows nothing about the signal modulation and content. Hence, you don't require an HDTV antenna to pick up the HD signal. An antenna has completely no notion what the signal resolution is. It might be HDTV, SDTV, NTSC, whatever. It is the job of a HDTV tuner and HD television set to demodulate the signal and to present the actual content on the screen.

Well, the antenna bandwidth and frequency response are not the only parameters that are important for clear TV reception. An antenna has other crucial electrical and spatial properties, like antenna gain (directivity) and high front-to-back (F/B) ratio. One might assume that an HDTV antenna must be far more powerful in terms of F/B and gain parameters. Does HDTV reception impose much more stringent requirements on antenna gain and F/B ratio?

There's a wrong, yet widespread belief that you will need far more antenna gain to receive digital television. I don't know where the hell this belief comes from, trigger the situation is precisely the opposite. HDTV has a lot greater noise and interference immunity than the analog television and can produce high high quality video at significantly lower signal-to-noise ratios.

Another critical specification, F/B ratio, has to do with the antenna ability to cope with a multi-path signal propagation from the towers to the receiving antenna. The higher F/B ratio is, the greater is multi-path rejection (also known as ghost suppression). With out going into technical details, we must say that HDTV signal is really a bit much more sensitive to multi-path trigger it has slightly larger bandwidth. Multi-path causes dips inside the signal spectrum, whereas we wish to keep the spectrum as flat as possible. When signal content is spread over a larger portion of spectrum it is a lot more likely to be distorted by multi-path. Basically, what TV equipment manufacturers are attempting to do in the so known as HDTV optimization would be to keep the spectrum flat inside the entire frequency band. It is critical for HDTV antenna to have a high F/B ratio in some areas where ghosts might be a problem. The point is, however, that most directional, old fashioned and cheap TV antennas have F/B ratio good enough to deal with multi-path propagation of HDTV signal and keep spectrum distortion at minimum. If an antenna can deal with an analog signal, it can handle a digital signal also.