Nonpool based spectrum sharing for two UMTS operators in the UMTS extension band

This paper investigates spectrum sharing (in the form of code sharing) between two Universal Mobile Telecommunication System (UMTS) operators in the UMTS extension band (2500-2690 MHz) with equal and unequal number of proprietary carriers, respectively. The paper proposes a dynamic spectrum allocation (DSA) algorithm to address the problem of spectrum sharing between two operators on a non-pool basis. It also investigates the impact of adjacent channel interference (ACI) on the spectrum sharing gain. Additionally, an architecture that enables spectrum sharing to take place between two or more UMTS operators is presented. The simulated performance of the proposed DSA algorithm shows that under peak-hour loading, up to 32% increase in capacity can be obtained when compared to currently used fixed spectrum allocation (FSA).