Fading in the baseband of the R&S®SMW200A and R&S®SMU200A signal generators or R&S®AMU200A base band generator is well proven and widely accepted for testing i.e. mobile radio standards as well as other applications. In most cases this is the better solution than RF fading simulators because signals are not degraded by the effects of the necessary multiple down- and up-conversions of an RF signal. Additionally, baseband fading is more economical. However, there are various applications where there is no alternative to RF fading, perhaps a baseband signal is simply not accessible.
Compared to a standalone fading simulator, the R&S RF Fading Simulator is a cost effective solution. Particularly if an R&S®FSW, R&S®FSQ, R&S®FSG or an R&S®FSV signal analyzer and an R&S®SMW, R&S®SMU vector signal generator are already available. As an alternative the Universal Radio Network Analyzer TSMW in combination with the IQR IQ data recorder can be used as digital IQ down-converter instead of a signal analyzer. The maximum demodulation bandwidth of this solution is limited by 20 MHz.
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