The Link Access Procedures on Dm channel (LAPDM) is the data link layer of GSM (Global System for Mobile Communications) cellular network. According to the requirements of virtual base station and 3GPP protocols, we proposed an improved scheme for implementing LAPDM on GSM virtual base station platform. The scheme has higher reliability and efficiency by reducing the useless data link status and operational flow. This paper introduced a framework for realizing the proposed scheme and presented detailed analyses about its program structure, status transition, errors detection and correction approach, timer and retransmission mechanism. Finally, the program was ported to the hardware platform and monitored by OT Drive software. Experimental results show the improved scheme has good performance on each required signaling flow.
Evaluation Methodology for Virtual Base Station Platforms in Radio Access Networks
