What technology does 5G network use? Why is 5G network faster than 4G network?

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What technology does 5G network use? Why is 5G network faster than 4G network? [Copy link]

In fact, it is not "5G is better than 4G", but "in order to be faster than 4G, the concept of 5G network was proposed". In fact, every generation of wireless communication network after 3G first proposes goals and then considers system design and technology.

Fast transmission rate

● Millimeter wave

The 300 MHz to 3 GHz spectrum used by the first to fourth generation of wireless communications has advantages such as penetration and wide coverage, but it has a fatal disadvantage: the frequency band is too narrow, there are a large number of wireless devices in the frequency band, and the spectrum allocation is about to be exhausted. In order to transmit large-capacity and high-speed data, only available spectrum can be found at 3 GHz.

The oxygen absorption band and water vapor absorption band in the millimeter wave spectrum (3 ~ 300 GHz) cannot be used for communication, so the millimeter wave band has a total bandwidth of 252 GHz available for use. In fact, the millimeter wave band allocated to 5G communication networks in the spectrum division of various countries is about 3~6 GHz, but it is enough to increase the data transmission rate by more than 10 times. (Again, the first four generations of commercial communication technologies are all crowded in the spectrum below 3 GHz).

● More advanced beamforming

The base station antennas of 4G networks are mainly omnidirectional antennas. Due to the narrow coverage of millimeter waves, large path loss, and severe impact of complex weather conditions, 5G networks need to focus the transmission energy through beam design to improve the quality of received signals. In fact, the directional beam after beamforming can help improve the coverage of base stations, and the base station signal energy is more effective.

● Ultra-large scale antenna

Multi-antenna systems in wireless communications require weighting of each antenna to improve spatial diversity, but in reality, this algorithm is nonlinear and computationally complex. Since millimeter-wave antennas have narrow beams and short antenna lengths, they are more suitable for ultra-large-scale antenna applications. Ultra-large-scale antennas may have a large number of applications in 5G, not just large macro base stations, but also small millimeter-wave transmitters that may be equipped with Massive MIMO systems.

Low transmission delay

● The best way to reduce signaling loss is to reduce unnecessary signaling, such as:

Reduce channel estimation time through full-duplex technology;

Reduce the CP prefix of OFDM signal and compress the OFDM length;

Grid-based design of millimeter wave base stations to reduce interference and latency.

● Compressed network processing

The standard way to compress the core network is to "not go through unnecessary processing units", in other words, to separate the control structure from the data transmission structure. It mainly uses "fog computing" (repetitive work below, using base stations as computing units) and "wireless caching" (caching content to reduce transmission delay) technology.

The fifth generation of communication technology is the result of tremendous efforts made by a large number of research institutes and universities. The 5G network is the result of the joint operation of the communication industry and academia. Only by perfecting the technical route and working together between industry and academia can the complete 5G network technology be achieved.