Performance of MIMO Downlink WiMAX at Application Layer

WiMAX, based on the IEEE 802.16 standard, is designed to support a variety of applications, including voice and multimedia services, through scalable OFDMA, advanced antenna techniques supporting MIMO, and well-defined quality of service classes. This paper presents WiMAX downlink achievable user goodput and operating range for different modulation and coding schemes for SISO and MIMO (both Space Time Block Code (STBC) and Spatial Multiplexing (SM)) connections. The achievable maximum goodput is shown to be between 94.5% and 97.0% of the theoretical data rates. The analysis is then expanded to multiple Subscriber Stations (SSs) and different packet sizes for a specific transmission mode, and also to multiple connections considering an additional real-time polling service (rtPS). The maximum goodput of Unsolicited Grant Service (UGS) is dropped to 51% and 58% when an rtPS is used for multiple connections due to the scheduling type.