With the rapid development of the digital age, communication technology is evolving at an unprecedented speed. As the fifth generation mobile communication technology, one of its biggest highlights is “low latency”. The so-called delay refers to the time required for data transmission from the sender to the receiver. In the 5G network, this time is compressed to the extreme, with a minimum of 1 millisecond, which is much lower than the 30-50 milliseconds of 4G. This remarkable improvement has not only changed people’s communication methods, but also brought revolutionary possibilities for time-sensitive application scenarios such as industrial automation, telemedicine and autonomous driving.
So, how does 5G achieve such a low latency? This is mainly due to the optimization of the following key technologies and network architecture.
First of all, ultra-reliable low-latency communication (URLLC) is one of the three major application scenarios of 5G, which is specially designed for services that require extremely high delay and reliability. With shorter subframe length, more compact scheduling mechanism and more efficient resource allocation strategy, URLLC effectively reduces the time of data transmission over the air interface.
Secondly, network slicing technology enables operators to customize their own virtual networks according to different business requirements. For example, the network slice designed for autonomous driving will give priority to the transmission of real-time data and ensure the millisecond response speed between the vehicle and the cloud. This “on-demand service” mode greatly improves the network efficiency and response speed.
Furthermore, the introduction of edge computing (MEC) is also one of the key factors to reduce the delay. In the traditional network, a large amount of data needs to be uploaded to the core network for processing, which leads to long transmission path and long delay. Edge computing, on the other hand, deploys computing power on base stations or edge nodes closer to users, thus realizing “nearby processing” of data, thus greatly shortening the round-trip time of data.
In addition, 5G adopts more efficient coding methods and higher spectral efficiency, such as LDPC codes and Polar codes, which not only improves the transmission rate, but also reduces the waiting time of data processing. At the same time, the application of large-scale MIMO and beamforming technology makes signal transmission more accurate and efficient, and reduces the delay caused by interference and retransmission.
Finally, the core network architecture of the 5G network has also been reconstructed, and the service-based architecture (SBA) has been adopted, so that each functional module can be called flexibly and respond quickly, further reducing the internal delay of the system.
To sum up, 5G has achieved unprecedented low latency through a series of technological innovations and network architecture adjustments. This is not only a leap in communication technology, but also provides solid technical support for emerging fields such as intelligent manufacturing, smart cities and remote control. In the future, with the development of 6G, low latency will be further optimized, and human society will move towards a smarter and more efficient direction.