--- a/src/wifi/model/yans-wifi-channel.cc	Thu Dec 15 16:21:44 2016 +0300
+++ b/src/wifi/model/yans-wifi-channel.cc	Thu Dec 15 16:44:18 2016 +0300
@@ -76,7 +76,7 @@
 void
 YansWifiChannel::Send (Ptr<YansWifiPhy> sender, Ptr<const Packet> packet, double txPowerDbm, Time duration) const
 {
-  Ptr<MobilityModel> senderMobility = sender->GetMobility ()->GetObject<MobilityModel> ();
+  Ptr<MobilityModel> senderMobility = sender->GetMobility ();
   NS_ASSERT (senderMobility != 0);
   uint32_t j = 0;
   for (PhyList::const_iterator i = m_phyList.begin (); i != m_phyList.end (); i++, j++)