Access methods to WiMAX femtocells: A downlink system-level case study

Over the last two years, GSM and UMTS femtocell access points have been proposed as a solution to the poor indoor coverage problem experienced in certain areas. Research on these devices has shown that femtocells will not only increase indoor system coverage, but also system capacity. Femtocells will allow new services and business models to be offered to indoor users. Almost parallely, the WiMAX standard has emerged as a potential candidate technology for the future wireless networks. WiMAX femtocells are currently under development and will therefore play an important role in the world of indoor broadband wireless access. However, several aspects of this new technology, such as the access method and interference avoidance techniques play a crucial role in the amount of interference caused to co-channel deployed macrocells. This paper provides a framework for the study of WiMAX macro-femtocell hybrid scenarios. An in-depth description of the necessary radio coverage prediction and system-level simulation for this kind of scenarios is introduced. Simulations and numerical results for two different types of access methods (public and private) in the downlink are also presented.