A Novel Method for Pilot Pattern Selection in 5G NR Systems

5G New Radio (NR) is a new wireless access technology which is developed by the 3rd Generation Partnership Project (3GPP) to meet the diverse performance requirements by various use cases. In addition, 5G NR system is set to provide seamless end-to-end connectivity for the large amount of connected devices in high mobility scenarios. 5G NR system is designed to support larger bandwidth in order to meet the high data rate requirements. A solution to estimate the channel response across the configured Bandwidth Part (BWP) is a challenging task due to variety of system configurations and diverse channel conditions at higher frequency of operation. The channel estimation techniques discussed in the literatures have not deeply analysed the performance and selection of 5G NR pilot patterns. This paper focuses on design of 5G NR Demodulation Reference Signal (DMRS) based pilot pattern for maximising the channel capacity by considering different channel models. Choice of usage of Modulation and Coding Scheme (MCS) adaptation against additional reference symbol transmission has been evaluated for a higher code rate transmission. 5G NR standard oriented framework is proposed to dynamically adjust the DMRS pattern as per target Block Error Rate (BLER) and feedback response. Trade-off between channel estimation accuracy and DMRS overhead is considered while designing the pilot pattern. It is observed from simulation results that, significant gain in throughput is achieved by the proposed scheme under specific traffic and channel conditions as compared to conventional schemes.