A study on homogeneous- and heterogeneous-based additional network deployments with application of coordinated multi-point operation

This paper studies additional cellular network deployments with the application of coordinated multi-point (CoMP) operation on the LTE-Advanced downlink. It clarifies which approach in additional deployment, either with a macro or pico base station (BS), is the most advantageous to CoMP and spectrum splitting. Cell splitting due to additional deployment is indispensable to having a huge network capacity, and there are two approaches in additional network deployment. One is a homogeneous-based additional macro BS deployment, and the other is a heterogeneous-based additional pico BS deployment. When CoMP is applied to additional deployment, additional macro deployment is preferable because additional macro deployment maintains the initial cost associated with the distribution of the rich backbone network required for simultaneous joint transmission. On the other hand, spectrum splitting is useful for additional pico deployment. Spectrum splitting means that a different spectrum is assigned to the additional BS although the occupied bandwidth for the original BS is reduced by half. System level simulations demonstrate that CoMP is superior to spectrum splitting with additional macro deployment in terms of average user throughput as well as 5% worst user throughput. The 5% worst user throughput gain due to CoMP is 56.8% compared to the original network deployment. On the other hand, spectrum splitting is superior to CoMP in additional pico deployment. However, the gain due to spectrum splitting largely depends on user distribution. If users are uniformly distributed, additional macro deployment with CoMP is superior to additional pico deployment with spectrum splitting, especially in terms of the 5% worst user throughput gain.