LAUSR

Device-to-device (D2D) communication technology can help base stations achieve high-capacity requirements. It is also a key technology for future markets. Moreover, the coexistence of licensed and unlicensed bands will be relevant to the landscape of the emerging fifth-generation cellular networks. However, there is a shortage of research on efficient transmission during the simultaneous use of licensed and unlicensed bands. This paper presents an efficient transmission algorithm involving a simple yet effective power assessment and round-robin-based bandwidth allocation from a system-level perspective in D2D-assisted cellular networks. The proposed algorithm, called “Efficient Transmission with Licensed and Unlicensed bands” (ETLU), enables data to be transmitted more efficiently over both kinds of bands. By using ETLU, bandwidth resources can be distributed more effectively based on traffic volume, greatly optimizing the average transmission rate by lowering the blocking ratio and increasing the ease of operation. Meanwhile, all transmitting users can be provided transmission rates that meet or exceed the average requirement of the system. With these advantages in mind, the present paper also includes a cost analysis of using ETLU. Successful simulation results verify that in terms of the average transmission rate and the blocking ratio, our newly proposed ETLU algorithm is indeed superior to extant algorithms. Due to its simple yet effective design, ETLU can be implemented easily and can serve as a good reference for mobile operators.