Over-the-air (OTA) HDTV becomes more and more popular. For someone who is used for noisy analog TV images, it is difficult to believe how amazing it can be a quality of HDTV broadcasts. In fact, HDTV channels has received over the air charge often have better quality than the same channels received through a paid subscription HDTV satellite. All you need to enjoy OTA HDTV is a HD TV with a tuner HDTV and HDTV antenna.
Eh? What kind of antenna?! If you have the pH. (d) in electrical engineering and have never heard of the type of antenna called "HDTV antenna", it is not because you were a bad student. HDTV antenna has nothing to do with physics and engineering. It was invented in the departments of marketing. Marketing found a trick to increase TV antenna. HDTV is a hot thing these days. Call essentially the same device HDTV antenna and it sells better. It makes people believe that they must buy an HDTV HDTV antenna or model optimized for watching HDTV broadcasts. This is very far from the truth.
HDTV antenna Hype has created a huge misunderstanding on TV antennas used to receive HDTV. This article is an attempt to clarify the issue.
You know what is a regular antenna? The antenna is a piece of metal designed to resonate at a specific frequency and be reactive above a certain range of frequencies. TV antennas are designed to work in the range of Ultra high frequency (UHF) and very high frequency (VHF) or both. Any transmitting station in VHF/UHF frequency, can be collected by a VHF/UHF antenna and transferred to television.
All broadcasts, digital and analog, are in the VHF and UHF bands. Over 90% of the HDTV broadcasts are UHF and less than 10% in the VHF band. It is important from the point of view that HDTV antenna falls in the bandwidth of a standard VHF/UHF antenna. Not HDTV antenna, antenna optimized HDTV not only an ordinary normal TV aerial. What makes a signal to be HD is its content, the way in which a signal is modulated and not the carrier frequency on which it is transmitted. Instead, the antenna knows nothing about the modulation of the signal and the content. Then, you don't need an HDTV antenna to pick up the HD signal. An antenna absolutely have no idea what is the resolution of the signal. Can be HDTV, SDTV NTSC. It is the work of a HDTV tuner and HD TV signal demodulation and to present the actual content on the screen.
Well, the answer of bandwidth and the frequency of the antenna are not the only parameters that are important for clear TV reception. An antenna has other important electrical properties and spatial, as antenna gain (directivity) and high ratio of double-sided (F/B). One might assume that an antenna HDTV should be more powerful in terms of F/B and gain parameters. Receiving HDTV impose stricter requirements on antenna gain and F/B ratio?
There is a widespread belief is wrong, you still need further gain antenna to receive digital television. I don't know where the hell this belief comes from, because the situation is exactly the opposite. HDTV has much better noise immunity and interference than analog television and capable of producing high-quality video to signal-to-noise ratios significantly lower.
Another important specification, F/B ratio, has to do with the ability to cope with an antenna for propagation of the signal path from the towers to the receiving antenna. The highest F/B ratio is, the better multi-path rejection (also known as ghost suppression). Without going into technical details, we must say that the HDTV signal is a bit more sensitive to multipath causing it has slightly bigger bandwidth. Multi-path causes falls in the spectrum of the signal, whereas we want to maintain more flat spectrum as possible. When the signal content is spread over a greater portion of the spectrum is more likely to be biased by multi-path. Basically, what the TV equipment manufacturers are trying to do optimization HDTV so named is to maintain a flat spectrum in the frequency band. HDTV antenna is important to have a high F/B ratio in some areas where ghosts could be a problem. The point is, however, that more directional, old-fashioned and cheap TV antennas have F/B ratio well enough to handle multipath signal propagation and keep distortion HDTV spectrum to a minimum. If an antenna capable of handling an analog signal, capable of managing a digital signal as well.
There is nothing specific about a TV antenna that is used to receive HDTV. When you choose an HDTV antenna, check really important parameters such as gain, directivity, F/B ratio. These specifications are important for the reception of transmissions, both digital and analog. Optimization of HDTV is probably the least important factor, which you should consider.
HDTV Antenna Labs presents step-by-step antenna selection guide and reviews. For more information visit http://www./HDTvAntennaLabs.com
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