Review the antenna technology in the terminal
The phone is full of antennas, from GPS, bluetooth, wifi, 2G, 3G, 4G and other frequency bands. The lower the frequency, the larger the size. Millimeter wave, as the name suggests, has a wavelength scale within 10mm, and calculated according to a quarter of the wavelength, a lattice of about 2.5mm forms an array with regular spacing.
4G antennas are generally arranged on the upper and lower ends and sides of mobile phones, using LDS (a manufacturing process of three-dimensional circuits, a laser selective metal deposition process on 3D curved plastics) and FPC (flexible circuit boards) with side metal frame to realize the terminal antenna function. In the metal body mobile phone, the exposed metal part of the middle frame and the FPC in the mobile phone form the antenna.
In 2017, glass body mobile phones became popular. The technology and materials to be used in this type of mobile phone are still FPC and LDS technology. There are also antennas made on glass shells and glass brackets: 0.1-0.2mm thickness 3D The frame touch and antenna phased array 4G antenna is the fastest growing 4G antenna in the 4G antenna field. Compared with other 4G antennas, the phased array 4G antenna has its special advantages.
1. High gain and high power
Because the electrically scanned 4G antenna does not need to roll the 4G antenna, the 4G antenna can be made very large. For example, some large phased 4G antennas have an area larger than a football field, and there are tens of thousands of 4G antenna units, so the gain can be very high. In addition, in order to increase the transmission power, more transmitters can be used to deal with the power tolerance of the antenna-feeder system when a single high-power transmitter is used. Therefore, the effect interval of the phased array radar 4G antenna can reach thousands or even tens of thousands of kilometers.
2. Multi-beam, multi-function
The 4G antenna beam can be divided and combined. When the target is far away, it can form a beam with extremely high gain and great power; when the target is close and there are multiple targets, it can be divided into many independent beams. multiple warheads) for finding and tracking. In addition, the generated multiple beams can also be used for alerting, tracking, guidance, etc., respectively, to achieve the effect of multi-purpose radar.
3. High data rate and precision
Because there is no mechanical rolling inertia, the beam can be pointed instantaneously and sensitively in the desired direction. 4G antenna beam response is extremely fast, so the data rate is high. Because the beam is very narrow, the azimuth of the target is determined with high accuracy.
4. High reliability
Because the 4G antenna is fixed, it can be made very strong. And 4G antennas have a lot of elements, and even if some of them fail, they can work normally. Because the operation of the phased array 4G antenna is very complex, it is impossible to complete all the operations by humans, and it generally needs to be used in conjunction with a computer, which further reflects the "fast" and "fine" advantages of the phased array 4G antenna.
The disadvantages of phased array 4G antenna are: high cost, high maintenance cost, limited scanning range, generally within 120° (because the scanning angle is too large, the function of 4G antenna will be deteriorated).
Because of the advantages mentioned above, phased array 4G antennas have been rapidly developed and widely used in recent years.
