diff -r 1b3d01bd974d src/devices/wifi/dcf-manager.h
--- ./src/devices/wifi/dcf-manager.h
+++ ./src/devices/wifi/dcf-manager.h
@@ -1,4 +1,6 @@
 /* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+#ifndef DCF_MANAGER_H_
+#define DCF_MANAGER_H_
 
 #include "ns3/nstime.h"
 #include "ns3/event-id.h"
@@ -283,3 +285,4 @@
 };
 
 } // namespace ns3
+#endif //DCF_MANAGER_H_