Coexistence model for compatibility between IMT-advanced and other wireless communication services

Abstract

This paper focuses on spectrum sharing between International Mobile Telecommunication-Advanced (IMT-A) and other wireless communication services. An enhancement to a current coexistence model that has been widely used in the studies on spectrum sharing is achieved. This model can be used in the study on any preliminary spectrum sharing between a newly introduced wireless communication system when less information of it is available and the existing systems. However, the current coexistence model has three limitations. (i) This model considers only the transmitter as the interference source and does not consider the receiver blocking as a second source of interference. This can lead to inaccurate results. (ii) This model utilizes the minimum coupling loss, which considers only a single victim and a single transmitter. This will result in a very large separation distance as it reflects the worst-case scenario. (iii) Finally, this model in turn uses the free-space propagation model to represent the path loss, which is applicable only to idealized cases. By considering the abovementioned limitations, our study proposes an enchantment to the current model to achieve feasible results and thus increase the spectrum usage. For a co-channel sharing scenario, the separation distance achieved by the current model is 80,000 km, whereas that achieved by the enhanced model is 240 km. Similarly, the adjacent channel distance achieved by the current model is 3.5 km for a 12-MHz frequency separation, whereas both the systems can coexist in the mentioned frequency separation. This shows that the enhanced model will eventually obtain more realistic results and achieve practical findings for more reliable compatibility results between the IMT-A or any newly introduced communication system and other wireless communication services.