Design and Implementation of a Multi-Threading Architecture for Downlink Process in Software- Defined Physical Layer Over Long-Term Evolution Networks

To engage with new and ongoing trends regarding the technical characteristics and potential uses of the 5th Generation Mobile Networks (5G), EURECOM (a leading European Graduate School and Research Center in the field of digital science in Sophia Antipolis, France) has been devoted to the realization of softwarization of the communication base station (BS) and has developed the open-source code OpenAirInterface. Such realization of the Evolved Node B (eNB) with Software-Defined Radio Access Network (SD-RAN) can transcend the bottlenecks of existing BS architecture and effectively increase transmission efficiency. Here, we analyzed and collated the physical layer (PHY) of the original downlink process in OpenAirInterface (OAI), and then reconstructed the software architecture to improve the computing efficiency for multiple users. The functionality of POSIX Threads (Pthreads) leads to a refreshed process that is packaged into sub-functions, and then passed into a number of newly opened threads for execution in order to i) establish the multi-threading PHY with parallel processing in OAI Downlink; ii) maximize the efficiency of the utilization of hardware resources; iii) reduce the execution time of the downlink process; and iv) expand the capacity of the user equipment (UE) connection and improve connection throughput. We physically used the OAI platform to implement a Long-Term Evolution (LTE) 3GPP-based softwarized BS test. Finally, real experiments show that the proposed approach can successfully parallelize the execution of the downlink process in OAI. This process effectively reduced execution time and offered broad scalability.