What is QMDL?

Detailed explanation

QMDL files are generated by the Qualcomm DIAG interface, a diagnostic port built into every Qualcomm-based mobile chipset. When activated, the DIAG interface streams raw diagnostic packets containing modem-level information that is not accessible through standard Android APIs. These packets are logged sequentially into a binary QMDL file.

The data captured in QMDL logs spans all protocol layers: Layer 1 (PHY statistics like CQI, MCS, BLER, MIMO rank, power control), Layer 2 (MAC and RLC statistics, scheduling grants, buffer status) and Layer 3 (complete RRC and NAS signalling messages in ASN.1 encoded format). Each entry is timestamped for precise correlation.

QMDL is the de facto standard for mobile network field testing and optimization. Post-processing tools parse these files to generate coverage maps, analyse handover sequences, identify interference patterns and benchmark network performance. The binary format is efficient for storage during long-duration drive tests that can generate gigabytes of data.

In addition to QMDL, HiCellTek supports export to Excel and CSV formats for engineers who prefer working with standard spreadsheet tools. The HLOG format provides an encrypted alternative for secure data handling. All export formats preserve the GPS coordinates, timestamps and complete measurement data from the original collection.