Fully integrated signal analysis for mobile WiMAX
While WiMAX was initially designed to replace broadband cable networks such as DSL, the adoption of the new IEEE 802.16e-2005 standard now also allows mobile applications. The R&S FSQ thus supports the IEEE 802.16-2004 OFDM and IEEE 802.16e-2005 OFDMA standards as well as WiBro, a variant of the WiMAX standard. To analyze WiMAX OFDMA signals transmitted by base stations, a downlink map is required. With the aid of this map, parameters such as the number of subscribers, assignment of subchannels, modulation modes, the number of active subchannels as well as type and number of permutation zones are covered. The R&S FSQ-K93 option includes a convenient editor for generating the downlink map. Results for all important parameters such as EVM, IQ impairments, frequency error and symbol clock error are displayed in a list in a straightforward manner. Since OFDMA uses different modulation modes, it is important to know the results of the individual subscribers. These are therefore shown in a submenu separately for each subscriber. In addition, constellation diagrams are generated to display specific parameters such as spectrum flatness. The combination with an R&S SMx signal generator from Rohde & Schwarz yields a complete measurement solution for verifying the physical characteristics of stationary and mobile WiMAX systems. The R&S SMU200A and R&S FSQ high-end instruments are particularly suitable for R&D applications, whereas the combination of the R&S SMJ100A and the R&S FSL is a preferable choice for production.