There is hardly a technology that is undergoing as much change as WiMAX. Rohde & Schwarz is a step ahead of this trend and offers component and receiver manufacturers a reliable reference solution. Users can regularly update their software options with new firmware to meet the latest technological requirements. The R&S SMx-K49 option allows users to generate WiMAX signals with 511 frames. Signal generators can thus provide complete PN9 sequences for bit error ratio measurements and ensure that test results are correct. Plus, the R&S SMU200A is the world's only instrument that optionally offers an integrated fading simulator and a two-path design. This makes the instrument ideal for testing transmit diversity and receive diversity systems. The new firmware update also makes it possible to generate signals with fully utilized subchannel allocation (FUSC) and partially utilized subchannel allocation (PUSC) permutations. These two methods allocate logical channels to physical channels. Furthermore, users can generate signals with multiple zones. Space time coding allows the receiver to process signals from more than one transmit antenna. The purpose of transmit diversity generated in this way is to increase data rates. The new tests can be enabled for all signal generators of the R&S SMx family by means of a firmware update. The R&S SMU200A, whose single sideband phase noise of typ. -135 dBc (1 GHz, 20 kHz offset) and wideband noise of typ. -151 dBc (1GHz, >10 MHz offset) are the best values in its class, is ideal for tests on WiMAX equipment.