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RF and microwave antennas, components, and systems, including mobile devices. MRI coils, radar, waveguides, SAR validation. AWR Axiem: commercial Yes Yes Yes Yes Yes Automatic, Hybrid MoM PCBs, multi-layer PCBs, LTCC, HTCC, on-chip passives, printed antennas. Integrated into Microwave Office. AWR Analyst: commercial Yes Yes Yes Yes Yes
DF9CY - EZNEC Simulation files collection - Antenna modeling files for EZnec and 4nec2. ARRL antenna modeling files - .NEC, .YAG, and .EZ files contributed by various sources. KK4OBI - Bent and other dipole models - This web site is devoted primarily as a resource for amateur radio operators to see what happens if they bend a half-wave dipole ...
German physicist Heinrich Hertz first demonstrated the existence of radio waves in 1887 using what we now know as a dipole antenna (with capacitative end-loading). On the other hand, Guglielmo Marconi empirically found that he could just ground the transmitter (or one side of a transmission line, if used) dispensing with one half of the antenna, thus realizing the vertical or monopole antenna.
The monopole antenna is essentially one half of the half-wave dipole, a single 1 / 4 wavelength element with the other side connected to ground or an equivalent ground plane (or counterpoise). Monopoles, which are one-half the size of a dipole, are common for long-wavelength radio signals where a dipole would be impractically large.
The driven element of the antenna is usually a half-wave dipole, its length half a wavelength of the radio waves used. The parasitic elements are of two types. A "reflector" is slightly longer (around 5%) than a half-wavelength. It serves to reflect the radio waves in the opposite direction.
A coaxial antenna (often known as a coaxial dipole) is a particular form of a half-wave dipole antenna, most often employed as a vertically polarized omnidirectional antenna. History [ edit ]
The LPDA normally consists of a series of half wave dipole "elements" each consisting of a pair of metal rods, positioned along a support boom lying along the antenna axis. The elements are spaced at intervals following a logarithmic function of the frequency , known as d or sigma .
A Yagi–Uda antenna, or simply Yagi antenna, is a directional antenna consisting of two or more parallel resonant antenna elements in an end-fire array; [1] these elements are most often metal rods (or discs) acting as half-wave dipoles. [2] Yagi–Uda antennas consist of a single driven element connected to a radio transmitter or receiver (or ...