A wireless antenna is a device that radiates radio frequency signals from a coaxial cable into the air or receives it from the air to a coaxial cable.
It converts guided waves propagating on coaxial cables into radio waves propagating in unbounded media, or vice versa. If you choose the wrong one, you will not get the proper function, or even burn the module seriously.
For the design scheme of a wireless network receiving and transmitting equipment used in the radio frequency system software, the design scheme and selection of the wireless antenna is a key part of it.
Excellent wireless antenna system software can achieve the best communication distance. The size of the same type of wireless antenna is positively related to the optical wavelength of the radio frequency signal. The lower the frequency of the data signal, the larger the wireless antenna required.
The wireless antenna can be divided into external antenna and built-in antenna according to the installation part.
The key of built-in antenna refers to the antenna that can be placed inside the machine and equipment. The key of built-in antenna includes FPC antenna, PCB antenna, spring antenna, ceramic patch antenna, laser immediate forming technology (LDS) and hardware spring antenna.
For small-sized products such as handheld equipment, wearing design solutions, and smart home systems, built-in wireless antennas are widely used, with high processing speed and beautiful appearance.
The Internet of Things technology and smart products must be connected to the network to transmit data, so wireless antennas must be used.
The smaller the indoor space and the more frequency bands, the more complicated the antenna design scheme, the external antennas are generally all standard materials, and the antennas in the required frequency bands can be used without adjustment.
For example, courier boxes and vending machines are widely used external wireless antennas that absorb magnetic fields, which can be absorbed on the tin case.
This kind of antenna cannot be placed in the iron filing cabinet. The metal material will shield the antenna data signal, so it can only be placed outside.
External wireless antennas can be divided into omnidirectional antennas and directional antennas from the perspective of the radiation source field.
Omnidirectional antenna: that is, it is mainly manifested as a 360° uniform radiation source on the horizontal pattern, which is usually said to have no specificity. On the vertical pattern, it is mainly manifested as a beam with a certain total width. Under normal conditions The smaller the total beam width, the greater the gain.
The external omnidirectional antenna mainly includes glass suction cup antenna, glass fiber reinforced plastic anti-corrosion antenna and hot melt glue stick antenna.
Directional antenna: It refers to a wireless antenna that transmits and receives radio waves in one or a number of special directions, while sending and receiving radio waves in other directions is zero or very small.
The purpose of selecting a fixed-item transmitting antenna is to improve the reasonable utilization rate of radiation intensity and improve safety; the key purpose of selecting a fixed-item receiving antenna is to improve the receiving sensitivity and improve the anti-interference. External fixed antennas mainly include tablet antennas, Yagi antennas and most cycle time antennas.