Compared with 4G antennas, 5G antennas have undergone revolutionary upgrades in multiple dimensions, which are mainly reflected in four aspects. First, in terms of antenna element quantity, 4G base station antennas usually adopt 2T2R, 4T4R, or 8T8R configurations (T stands for transmit, R stands for receive), while 5G base station antennas, driven by Massive MIMO technology, have increased the number of antenna elements to dozens, hundreds, or even thousands. Common configurations include 32T32R, 64T64R, 128T128R, and even 256T256R. The substantial increase in the number of antenna elements is the core basis for 5G to achieve high capacity and high spectral efficiency. Second, in terms of operating frequency bands, 4G antennas mainly operate in the sub-3GHz low and medium frequency bands, while 5G antennas adopt a dual-track development pattern of Sub-6GHz and millimeter wave (mmWave) frequency bands. The Sub-6GHz frequency band (mainly 3.5GHz, 4.9GHz, etc.) has the advantages of strong penetration and wide coverage, and is mainly used for macro coverage and deep coverage; the millimeter wave frequency band (above 24GHz, mainly 28GHz, 39GHz, etc.) has a large bandwidth, which can achieve ultra-high-speed data transmission, but has the characteristics of large path loss and weak penetration, and is mainly used for high-density coverage scenarios such as urban central areas, stadiums, and indoor venues. Third, in terms of signal control capabilities, 4G antennas mainly adopt omnidirectional or sectoral radiation modes, and the signal coverage is relatively fixed, while 5G antennas, relying on beamforming technology, can precisely control the direction, width, and shape of signal beams, realizing "beam focusing" and "dynamic tracking" of user equipment, which greatly improves signal strength and reduces inter-user interference. Fourth, in terms of structural integration, 4G antennas usually adopt a separate design of passive antennas and remote radio units (RRU), while 5G antennas tend to adopt an Active Antenna Unit (AAU) integrated design, integrating antenna elements, radio frequency front-end modules (power amplifiers, low-noise amplifiers, filters, etc.), and even part of the signal processing functions into a single physical module. This integrated design not only reduces the volume and weight of the antenna, simplifies installation and deployment, but also reduces signal transmission loss between components, improving overall system efficiency.
