Over-the-air HDTV (OTA) is becoming increasingly popular. For anyone who is used to high analogue TV images, it's hard to believe how incredible the quality of HDTV broadcasts is. In fact, the HDTV channels received for free in the air are often better quality than the same channels obtained through a paid HDTV subscription. All you need to enjoy the OTA HDTV is an HDTV with a built-in HDTV tuner and an HDTV antenna.
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Huh? What kind of antenna? If you have a Ph.D. in electrical engineering and never heard of the type of antenna called "HDTV antenna", it's not because you're a bad student. The HDTV antenna has nothing to do with physics and technology. Marketing has found an effective trick to increase the sales of television antennas. HDTV is now hot. Connect mainly with the same HDTV antenna device and sell better. This makes people believe they need to buy an HDTV model or an optimized HDTV antenna to watch HDTV broadcasts. The hype of the HDTV antenna has used a huge misunderstanding regarding TV antennae for HDTV reception. Antenna is a piece of metal that is designed to resonate at a particular frequency and responds to a particular frequency range. TV antennas are designed to work in the High Frequency Range (UHF), in the High Frequency Range (VHF) or in both cases. Any station that is transmitted in the VHF / UHF frequency bands can be retrieved from a VHF / UHF antenna and sent to the TV.
All TV shows, digital and analogue are in the VHF and UHF bands. What is important from the point of view of the antenna is that the HDTV is in the bandwidth of a regular VHF / UHF antenna. No HDTV antenna, no optimized HDTV antenna, just a normal, normal TV antenna. What the signal HD makes is its content, the way a signal is modulated and not the carrier frequency on which it is transmitted. On the contrary, the antenna knows nothing about signal and content modulation. You do not need an HDTV antenna to record the HD signal. An antenna has absolutely no idea what the signal resolution is. It can be HDTV, SDTV, NTSC, whatever. It's the work of an HDTV tuner and HD TV to demodulate the signal and display the current content on the screen.
An antenna has other important electrical and spatial features, such as antenna increase (directional characteristics) and high front / rear ratio (F / B). It can be assumed that an HDTV antenna must be stronger compared to F / B and get parameters. Does HDTV reception require stricter antenna increase requirements and F / B ratio?It's a misconception, but general that you need more antenna gain to receive digital television. HDTV has much better sound and immunity than analogue TV and can produce high quality video with significantly lower signal and sound.
Another important specification F / B ratio has the ability of the antenna to make a multipath signal propagation from the tower to the receiving antenna. Without going into technical details, we have to say that the HDTV signal is a bit more sensitive to multipath because it has slightly higher bandwidth. Multi-path causes dips in the signal spectrum, while keeping the spectrum as flat as possible. Basically, some TV equipment manufacturers are trying to do in so-called HDTV optimization to keep the spectrum range over the frequency band. If an antenna can process an analog signal, it can also process a digital signal.
There is nothing special about a TV antenna used to receive HDTV. When selecting an HDTV antenna, check the really important parameters such as directivity, profit, F / B ratio.