Overview of the characteristics and applications of flat panel antennas!

　　Overview of the characteristics and applications of flat panel antennas!

　　"Flat-Panel Antenna", also known as planar antenna or patch antenna, is a microwave antenna with a flat structure and low profile. Unlike traditional parabolic antennas or convex antennas such as Yagi antennas, its radiating elements and feed networks are usually made on a flat dielectric substrate.

　　The following are the main characteristics and applications of flat panel antennas:

　　Core Features

　　Low profile and thinness: The biggest advantage is its flat structure, which is usually only a few millimeters to a few centimeters thick. This makes it very easy to install on walls, roofs, cabin shells, satellite terminals, mobile devices and other scenes with limited space or requiring streamlined design.

　　Easy to integrate and conformal: The planar structure makes it easy to integrate into various device housings or platforms (such as drones, cars, portable terminals), and can even be made into curved surfaces (conformal antennas).

　　Low manufacturing cost (in large quantities): It is usually manufactured using printed circuit board technology, and the cost is relatively low in large-scale production.

　　Lightweight: It is mainly composed of dielectric substrate and metal foil, and its weight is much less than that of parabolic antennas of the same caliber.

　　Aesthetics and concealment: The flat appearance is more beautiful and easier to hide or camouflage (such as embedding in walls and car bodies).

　　Flexible polarization: It can be designed as linear polarization (horizontal or vertical) or circular polarization (left-handed or right-handed).

　　Can be designed into an array: It is easy to arrange multiple radiating units (patches) into an array, and by controlling the feeding amplitude and phase of each unit, beamforming, beam scanning (phased array) or gain improvement can be achieved.

　　Disadvantages/Challenges

　　Relatively narrow bandwidth: The bandwidth of a single patch is usually narrow (several percent to more than ten percent). Although it can be improved through design techniques (such as multi-layer, slotted, coupled feeding, etc.), it is still not as good as some broadband antennas.

　　Gain and efficiency: At the same physical size, the gain is usually lower than that of traditional parabolic antennas. Efficiency may also be affected by dielectric loss and conductor loss.

　　Limited power capacity: Limited by the power resistance and heat dissipation of dielectric materials, it is usually not suitable for high-power transmission applications.

　　Design complexity (especially arrays): The design of high-performance or scanning arrays, feed network design, and mutual coupling effect processing are relatively complex.

　　Main technology types

　　Microstrip patch antenna: The most common type of flat antenna. It consists of one or a group of metal patches etched on a dielectric substrate and a ground plane at the bottom.

　　Printed slot antenna: A slot of a specific shape is etched on the ground plane for radiation.

　　Flat slot waveguide antenna: Slots are cut on the wide wall of the waveguide to form radiation. The performance is usually better than that of microstrip patches, but the structure is slightly more complicated.

　　Array antenna:

　　Passive array: Fixed beam, increase gain and directivity through the array.

　　Active phased array: Each radiating unit or subarray is connected to an independent T/R component, which can electronically scan the beam direction without mechanical rotation. This is the most advanced and high-performance form of flat antenna, widely used in radar, satellite communications, 5G base stations, etc.

　　Main application areas

　　Satellite communications:

　　Satellite TV reception (Ku band).

　　Satellite Internet access terminals (such as Starlink, OneWeb and other user terminals).

　　Mobile satellite communications (maritime, aviation, vehicle-mounted).

　　Satellite data acquisition.

　　Wireless communications:

　　Cellular mobile communications (4G LTE, 5G) base station antennas (especially massive MIMO antenna arrays).

　　Wi-Fi router/access point antennas.

　　Bluetooth device antennas.

　　RFID reader antennas.

　　Global Positioning System: GPS, GLONASS, Galileo, BeiDou receiving antennas (usually circularly polarized patches).

　　Radar:

　　Automotive radar (blind spot monitoring, adaptive cruise control - 77/79 GHz).

　　Security radar.

　　Drone radar.

　　Airborne/spaceborne synthetic aperture radar.

　　Radio frequency identification: RFID reader antenna.

　　Internet of Things: Various IoT devices that require embedded antennas.

　　Aerospace: Aircraft communication, navigation, and data link system antennas.

　　Portable devices: Portable communication devices with high requirements on size and weight.