I've observed this recently with my wireless/hardware configuration. Has anyone else encountered a similar issue?

When I shutdown my laptop, the other wireless devices connected to the same router have a moment (5 seconds) of unable to connect. Everything returns in a few seconds. Router logs don't appear to indicate a failure.

Laptop: IBM Thinkpad T61
NIC: 03:00.0 Network controller: Intel Corporation PRO/Wireless 4965 AG or AGN [Kedron] Network Connection (rev 61)
Router: D-Link DIR-655 - Hardware version: A4, Firmware version: 1.21