From time to time there are reports about new inventions "new antennas with special physical properties". So 40 years ago there was a boom of "watermark" antennas, collected in an ordinary light bulb filled with distilled water, went to pvp "the special properties of mercury antennas", etc. Periodically, the younger generation learned that in materials with dielectric constants greater than 1 length of the electromagnetic wave is less than in air or vacuum. This circumstance pushed them on "invention" supercompact but a full-sized antennas with all the ensuing benefits. So Epsilon near the water about 80, respectively, and the antenna can be reduced at the same time. Today we are talking about modern composite materials with a dielectric constant much greater than 1 and the antennas based on them. Really are working antenna can be created, and are created by different companies, for example for satellite reception. But these working antenna subminiature not, as specified in the prospectus.

The amount of energy of radio waves incident on a certain surface, is directly proportional to the area of the surface and no "shamanic dances with a tambourine" it is impossible to increase. NO composite materials or gold plating cannot change this law of nature.

Well, these small-sized antenna bluff or deception? No! They can work and be useful, but not due to the use of special composite materials". As you can tell from discussing prospect, we're not just talking about the antennas, and the antenna beamwidth amplifier, otherwise "active antennas".

To enable radio reception, the level of the useful signal delivered to the input circuits of the receiver (TV), as a minimum, must exceed the level of their own noise last, reduced to its entrance. To improve the signal-to-noise radio receivers tract long been using antenna amplifiers mounted directly near or on foster the aerials. The lead-in cable to the receiver (the TV) is already amplified signal, so cable loss or noise induced on it, not so much impair the reception. Besides, if own noise (noise temperature) of the antenna amplifier is less than the receiver (the TV) that improve the reception will be observed even when installed antenna amplifier below, directly at the entrance receiver. Such amplifiers, using modern low-noise transistors, exist and are constantly improving.

Now used in the antenna of composite materials allows to create compact, broadband, optimum receiving antennas the main drawback of which is low level of the accepted (because of its small square) of the signal is compensated by a built-in antenna amplifier. And such synthetic antenna systems can replace the traditional full-size "air" antenna.

Moreover, their small size adds a new quality to them - the spatial positional selectivity. In the city due to the multiple reflections, pereizlucheniya and signal interference fields radio waves have a very complex spatial structure. Traditional full-size receiving antennas is influenced and useful signal and its reflection causing the repeats, edging, fading and high noise on the TV screen. Very often spatial location or orientation the directivity of these antennas can not completely get rid of these shortcomings, especially in the broadband reception. With an antenna of small dimensions, of course, easier to find a point in space with minimum interfering influences. But the signal field is constantly changing due to weather conditions, changes in construction and many other factors. Because these miniature antennas especially promising as antennas, easily transported by the user for better reception quality.

As for long and ultra-long reception that a full-sized directed antenna, with the same low-noise antenna amplifiers, will always take precedence over small-sized quality, and the possibility of receiving a signal.

Unfortunately, in discussing advertising Avenue as often happens in advertising, in my opinion, there are errors and inaccuracies:

"Currently applied in various kinds and types of receiving-transmitting antennas have various drawbacks, and the main one is the large size (up to 10 m)."

Big antenna isn't it? Not worth the small antennas-alternatives to ascribe the ability to effectively to emit the signal as a normal antenna. Their lot is the radio reception.

"A new approach to the physical process of transmission and reception of electromagnetic waves based on the theory of reducing the wavelength of the electromagnetic wave in the volume a composite material using a composite material as the active element of the antenna-feeder device with energy potential

And what's new? Dielectric antennas are known for a very long time, including active. Antenna in composite materials made at the Tiraspol factory "Moldavizolit" 15 years ago... and I want to append "... and receiving the signal directly from the noo!"

"The opportunity to significantly increase the density of radio channels in operation the frequency range"

What?! The antenna will condense the radio? Fantastic! If you mean polarization isolation of groups of channels, it can make any antenna with polarization waves.

"Reducing energy radio

Brad, what that! Radio engineers use more powerful transmitters and antennas with high gain to INCREASE energy radio channels and improve the signal-to-noise ratio. Same here happy return?!

"The reception quality of the signal when the antenna dimensions significantly less than counterparts without inferior to the ‘big’ traditional antennas"

It is not correct to compare antennas active and normal. And even then this is possible under certain conditions (urban). The same comparison clean antenna devices of the same configuration will never reveal even the alleged equality of these antennas.

"The opportunity to work on a reflected wave in terms of intermodulation distortion"

Maybe this refers to the interference signal? Intermodulation distortion is a bit different... not from the field of antennas, a characteristic of amplifiers, receivers, transmitters.

"Information on the issue or the development of alternative antennas using technology of this level (at the time of obtaining a patent) is not available"

Patent can and a paper clip by changing its shape or covered with plastic, so that it is not rusted and soiled papers...

In the Radio magazine 25 years ago was described active CB car antenna LW range in similar sizes providing equivalent active height of several meters. Not less than 6 years firm Lucent Technologies uses in his stations of cellular CDMA GPS receivers with an active satellite. It consists of 5 cm multi-start spiral and solid-state amplifier providing a total gain of 28 dB. There are also many portable GPS receivers.... So, there's something in the world is made.

And finally, I want to say about the place where a miniature broadband antenna can be definitely very useful - in parabolic or other reflector antennas.

Parabolic antenna broadband initially, spoil escapologist their irradiators. After collecting the parabola signal at (spot) it's hard to make a puller for it because traditional antenna elements are too large. Therefore, for example in MMDS networks make the parabola with different surface curvature in orthogonal planes, adjusting her focus to used linear irradiator. The use as feed miniature dielectric antenna will create a truly broadband antennas with high gain based on of a paraboloid of revolution.

Summing up, I would say that miracles do not happen, and for all you have to pay or sensory loss or additional costs for low-noise and wideband amplifier with power supply. And crackling advertising is just a marketing ploy.

Author: E. shoustikov, UO5OHX ex RO5OWG; Publication: www.shustikov.by.ru, www.cxem.net

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