The "array method" of the antenna array

These antennas combine signals with each other to achieve higher performance than separate antennas. The antenna array can increase the overall overall gain, achieve diversity reception, compensate for interference, adjust to specific pre-alignment, measure the source direction of the input signal, and maximize the signal to interference noise ratio (SINR). Antennas usually consist of more than one dipole, but they also consist of resonant active dipoles. The antenna elements in the array radiate separately, and the radiation of all the elements are added together to form a radiation wavelength with high gain, high directivity, high performance, and the lowest loss. Similar to the dipole, the active vibrator also resonates both the transmitter and the receiver. When connected to a transmission line, the active vibrator directly obtains energy from the transmission device, or acts as a receiver, directly transmitting the received electrical energy to the receiving device. Applications include satellite communications, wireless communications, radar communications, and astronomy research.

Antenna frame type

When the distance between the parasitic vibrator and the active vibrator is close enough to break and exchange, the corresponding driver of the parasitic vibrator will generate the largest amount of emitted radiation. The parasitic oscillator that can increase the power from the driver is called the director, and the parasitic oscillator that can maximize the radiation energy to the active oscillator is called the reflector. When all the elements inside the antenna have active elements, the array is also called active array or connection array. Interestingly, once the layout includes one or more parasitic oscillators, the entire system is called a parasitic array. Multivariate cocoa is classified according to its directionality. For example, an array that radiates in two opposite directions is called a bidirectional array, and an array that radiates in only one direction is called a unidirectional array.

One, active array

Collinear array

Collinear wiring is a unidirectional high-gain antenna containing two or more half-wave dipoles. These dipoles are connected head to tail on the same straight line or line to form a parallel or collinear structure. The main purpose of this type of array is to increase the radiated power and achieve high directional subdivision by avoiding power loss in other directions. The advantages of collinear antennas include improved directivity and reduced power loss.

Vertical frame

The pendant array is a bidirectional array that improves the emission performance by radiating electromagnetic waves in a specific direction. The design element of this type of array includes two or more half-wave dipoles, all of which have the same size, and the radiation pattern along the vertical line antenna is perpendicular to the above-mentioned vertical, the radiation length is narrow, and the gain is higher.

End shot frame

Similar to the pendant array, the endfire array also uses two half-wave dipoles separated by half a wavelength, and has a bidirectional radiation pattern. , Higher directionality. The radiation direction in the end shooter is parallel to the array plane and perpendicular to the vibrator, and the radiation direction of the vibrator is toward the end of the array, then the radiation direction of the array is consistent with the radiation direction of the vibrator.

Second, the parasitic grid

Yagi Uda Architecture

The most commonly used antenna in home antenna reception has the characteristics of high gain and high directivity. This type of antenna has multiple guides, and the directivity of the antenna can be improved by setting the guides. The disadvantage of the Yagi-Uda antenna is that it is easily affected by noise and the ambient atmosphere.

Log periodic array

Similar to the Yagi-Uda antenna, the log-periodic antenna has the advantage of maintaining constant radiation resistance, standing wave ratio, gain and directivity ratio within the required operating frequency range. Log periodic antennas include planar log periodic antennas, trapezoidal log periodic antennas, toothed log periodic antennas, V-shaped log periodic antennas, slot log periodic antennas, dipole log periodic antennas and LPDA (log periodic even Polar array) and other types.

Wound pole frame

The basic structure of this type of antenna is two identical half-wave dipoles placed at right angles to each other and fed in phase. The gain can be increased by stacking multiple rod-around antennas vertically. This structure is called a stacked array. The working mode of the rod antenna is divided into normal and two modes, and the conversion mode is different under different working modes. In the normal mode, the antenna radiation wave is horizontally offset, and the offset direction is perpendicular to the antenna axis. In the initial mode, the radiated wave is a circularly polarized wave around the antenna axis.

Super winding frame

The super-wound rod array is the so-called batwing antenna, in which the dipole in the winding rod antenna is replaced by 4 plates, and 1 to 8 stacked arrays can be set on a single winding rod. The advantage of this type of array lies in the gain and directivity of the coaxial common whirling rod antenna, but at the same time there is a certain power loss.