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The development of antennas is closely related to the development of radio technology. All kinds of antennas are designed to meet the practical requirements put forward at that time.
The first antenna was designed by H. R. Hertz of Germany in 1887 to verify the existence of electromagnetic waves proposed by J. C. Maxwell of England. Loop antenna for receiving antenna. In 1901, G. Marconi of Italy first used large antennas to realize ocean communications. The first practical T-type transmitting antenna uses 50 drooping copper wires, the top of which is connected with horizontal lines and is hung on two supporting towers.
The main application of early radio is long wave transoceanic communication, and the development of antennas is focused on long wave band. The characteristics of long wave antenna are large load capacity, large structure and low efficiency.
After 1925, radio broadcasting began to prevail and omnidirectional MW antennas developed gradually. The earliest medium wave antennas are T, inverted L and umbrella shaped antennas. In order to overcome the over-amplitude modulation distortion caused by sky-wave interference fading, the cable-type and self-supporting tower antenna are designed. The height of the vertical antenna can not only be very high, but also can concentrate the energy of the vertical polarization wave to radiate in the direction of the ground, reduce the radiation of the high elevation angle horizontal polarization wave, weaken the influence of sky wave fading, and expand the effective coverage of the ground wave.
Around 1925, it was found that short-wave and long-distance communication could be carried out by using ionospheric reflection, and the power needed could be greatly reduced, so the directional short-wave antenna developed rapidly. Various types of horizontal antennas and antenna arrays are designed, including in-phase horizontal antennas, double-wave antennas and broadband traveling-wave diamond antennas.
Although the wave channel antenna (commonly known as Yagi antenna) was proposed by Yagi and Yuta in 1927, it was not until 40 years later that Yagi antenna was developed and applied with the solution of oscillator sources and the development of ultra-short wave communication. As early as 1888 H.R. Hertz had proposed the idea of parabolic reflector antenna, until 1937 was really put into practice. The horn antenna came into being in 1930s with the development of waveguide technology. During the Second World War, due to the development of radar technology, microwave antennas developed rapidly. Parabolic antenna, lens antenna, dielectric rod antenna, slotted antenna and so on all have different degrees of progress in this period. The development of parabolic antenna is particularly prominent, including the design of the reflector, beam scanning and the generation of shaped patterns.
After World War II, with the development of microwave relay communication, ultra-short wave mobile radio, television broadcasting and radio astronomy, and the rise of scattering communication, monopulse radar and synthetic aperture technology, broadband batwing TV transmitting antenna, microwave relay periscope antenna, quasi-non-frequency variable logarithm antenna appeared one after another. Periodic antennas and isometric spiral antennas. Since the advent of satellites and intercontinental missiles in the late 1950s, due to the urgency of arms competition and the need for electronic countermeasures, antennas are required to have high-gain, high-resolution, fast scanning, accurate tracking and other high-parameter performance, as well as circular polarization, broadband, multi-function and common to meet the needs of aircraft. Shaped and embedded. From the 1960s to the early 1970s, the main achievements of antenna development were as follows: (1) the new construction and improvement of large earth station antenna, including the application of Cassegrain antenna, feed, main and secondary reflectors, beam waveguide and other technologies; (2) phased array: due to the improvement of phase shifters, the application of electronic computers, remote warning and rapid response Much progress has been made in the search and tracking of multiple targets at the same time. 3. Many large radio telescopes with typical significance. In addition, antennas with small apertures, such as loaded antennas, backfire antennas, active antennas, and antennas on aircraft (including aircraft, rockets, missiles, satellites) also made important progress during this period.
In the 1970s, with the development of radio technology toward millimeter, sub-millimeter and even light waves, frequency multiplexing, orthogonal polarization, near-field measurement, multi-beam and defocus bias, signal processing, synthetic aperture and adaptive antennas for microstrip antennas, surface wave antennas, conformal arrays and reflector antennas were also affected. Attach importance to and develop accordingly.
In the 1980s, besides continuing to explore and improve the antenna's type and performance in the exploited band, a great deal of research work has gradually turned to the transmission and reception of transient electromagnetic waves, the scattering and inverse scattering of targets, the solution of electromagnetic boundary value problems, the radiation and scattering of antennas in special media and so on. Research.