Adaptive coverage for UMTS macrocells based on situation awareness

The paper examines the capability of extending base station sector beams in order to assume coverage in a partially or fully failed neighbouring cell. Increasing the transmit power of the sector to reach out for new users is not possible in UMTS since it increases interference in the system. This paper considers how adaptive coverage can be implemented in practice. Analysis suggests that performance is downlink-limited. A balanced link power algorithm is required to provide the extra power for increasing the range capability of the sector. Furthermore, it is found that up to 25% of users (premium rate customers) in a failed heavily loaded cell can be supported by sector extension. This figure approaches 100% for a lightly loaded cell, or the more practical case of sector failure. In all cases, SA significantly enhances the number of users that can be supported anywhere in the failed cell