Latency Analysis and Reduction in a 4G Network

Abstract

5G, the next generation of mobile network, is expected to be launched commercially around 2020. Compared to the present generation – 4G mobile network, a significant improvement in terms of performance and reliability is considered for 5G. One of the important factor in the design of 5G is – about 10 times lower packet latency than 4G. Some of the use cases identified for 5G require packet latency as low as 1 ms. Such stringent latency targets are essential to enable new services like virtual reality streaming of live content over mobile network, automated vehicle platooning over mobile network and tactile internet where machines and tools can be controlled remotely with extreme responsiveness over the mobile network.
The main goal of this thesis is to understand how packet latency is affected by the various factors observed in a realistic environment. In contrast to lab environments, where the packet latency reported would be very low, a consolidated study on the various factors affecting packet latency in a 4G (LTE) network in a realistic environment is missing. To this extent, the results of this work have enabled to identify the various factors affecting packet latency in a realistic 4G network. This further led to identifying the latency contribution of the various components to the overall packet latency. Later on, two different latency reduction techniques were evaluated to verify the possible latency reduction achievable on a 4G network, using those two techniques.
To reduce packet latency to achieve the latency targets for 5G, first it was necessary to identify how packet latency is caused and affected in a 4G network. This work was aimed at achieving this goal. As the latency reduction techniques were evaluated at their best configuration in terms of latency, results from the latency reduction techniques also identifies the lower limit of latency improvement achievable in a 4G network. The inference from the results suggests that in order to achieve the latency targets specified for 5G networks, a redesigned radio access technology of 4G is essential.