The USB Wireless Modem Diagnostics Interface driver is a software component used by Windows to communicate with a USB modem device (typically a wireless modem). This driver facilitates the connection between your system and the modem, allowing Windows to recognize the modem and use its capabilities, such as establishing an internet connection or enabling mobile network access.

In particular, the Diagnostics Interface allows communication between the operating system and the modem, typically for diagnostic purposes, like checking signal strength, troubleshooting connectivity issues, or managing modem settings.