This application note focuses on key measurement issues for WLAN and combo devices, how the RTSA addresses those issues, and why traditional signal analyzers are not adequate. We begin with a brief overview of the key concepts of real-time spectrum analysis, including the ability to flexibly trigger on RF signals, seamlessly capture them in memory, and perform time-correlated multi-domain analysis based on a variety of wireless standards. Next, the WLAN measurement analysis software available for the RSA3408A Real-Time Spectrum Analyzer is reviewed. Finally, we explore some of the real-world problems encountered with wireless combo devices that can be solved using the RSA3408A. Issues like packet collisions between Bluetooth and WLAN devices, internal interference caused by poor filtering and poor shielding in a GSM/WLAN device, and the unwanted interactions between RF packets and high-speed digital logic circuits are explored.