--- a/src/wifi/model/wifi-phy.cc	Fri Mar 27 10:03:43 2015 -0700
+++ b/src/wifi/model/wifi-phy.cc	Fri Mar 27 11:28:59 2015 -0700
@@ -55,6 +55,7 @@
 {
   static TypeId tid = TypeId ("ns3::WifiPhy")
     .SetParent<Object> ()
+    .SetGroupName ("Wifi")
     .AddTraceSource ("PhyTxBegin",
                      "Trace source indicating a packet "
                      "has begun transmitting over the channel medium",