QXDM

QXDM is the tool you reach for when you need to see what a Qualcomm-based UE is actually doing on the air, message by message, in real time. It taps the chipset's diagnostic interface and surfaces the layers you care about — NAS, RRC, MAC/PHY, plus a pile of RF and internal state info — as the device runs. On a drive test or in a lab, it's how you watch a registration, an RRC setup or a handover unfold live and catch the exact point something goes wrong.

A couple of field notes. QXDM is real-time capture; its companion QCAT is for chewing through the logs afterwards, and the normal workflow is to record an ISF/DLF log in QXDM and analyse it in QCAT later. It's Qualcomm-specific — for other chipsets you'll be in a different vendor's diagnostic tool, and for the network-side air interface you'd be looking at over-the-air traces or an analyzer rather than QXDM. The practical barrier most people hit isn't the software but access: the diagnostic port and the right logging permissions are gated, so you generally need an engineering or vendor-enabled device rather than an off-the-shelf retail handset to get the full message detail.