Data rates and radio link adaptation in WiMAX

International audienceWiMAX is a very promising Broadband Wireless Access (BWA) System. Four digital modulations and many channel coding possibilites are provided in WiMAX which gives way for many modulation and coding schemes. We start by reminding these schemes and the associated robustness for each scheme. Link adaptation is the possibility to change modulation and coding scheme according to the radio link quality in order to have a high global efficiency. This procedure is not limited to WiMAX. For example, it was already included in GSM/EDGE. We remind the channel bandwitdhes and data rates of GSM/EDGE, UMTS and WiFi (in its two physical layer variants: 802.11a and 802.11b). The spectral efficiency of each system for the different proposed modulation and coding schemes are given. We also review some recent research paper