diff --git a/src/wifi/model/interference-helper.cc b/src/wifi/model/interference-helper.cc
index fc6e5efea..543bbb5ee 100644
--- a/src/wifi/model/interference-helper.cc
+++ b/src/wifi/model/interference-helper.cc
@@ -33,9 +33,8 @@ NS_LOG_COMPONENT_DEFINE ("InterferenceHelper");
  *       Phy event class
  ****************************************************************/
 
-InterferenceHelper::Event::Event (uint32_t size, WifiTxVector txVector, Time duration, double rxPower)
-  : m_size (size),
-    m_txVector (txVector),
+InterferenceHelper::Event::Event (WifiTxVector txVector, Time duration, double rxPower)
+  : m_txVector (txVector),
     m_startTime (Simulator::Now ()),
     m_endTime (m_startTime + duration),
     m_rxPowerW (rxPower)
@@ -70,12 +69,6 @@ InterferenceHelper::Event::GetRxPowerW (void) const
   return m_rxPowerW;
 }
 
-uint32_t
-InterferenceHelper::Event::GetSize (void) const
-{
-  return m_size;
-}
-
 WifiTxVector
 InterferenceHelper::Event::GetTxVector (void) const
 {
@@ -138,11 +131,11 @@ InterferenceHelper::~InterferenceHelper ()
 }
 
 Ptr<InterferenceHelper::Event>
-InterferenceHelper::Add (uint32_t size, WifiTxVector txVector, Time duration, double rxPowerW)
+InterferenceHelper::Add (WifiTxVector txVector, Time duration, double rxPowerW)
 {
   Ptr<InterferenceHelper::Event> event;
 
-  event = Create<InterferenceHelper::Event> (size, txVector, duration, rxPowerW);
+  event = Create<InterferenceHelper::Event> (txVector, duration, rxPowerW);
   AppendEvent (event);
   return event;
 }
@@ -153,7 +146,7 @@ InterferenceHelper::AddForeignSignal (Time duration, double rxPowerW)
   // Parameters other than duration and rxPowerW are unused for this type
   // of signal, so we provide dummy versions
   WifiTxVector fakeTxVector;
-  Add (0, fakeTxVector, duration, rxPowerW);
+  Add (fakeTxVector, duration, rxPowerW);
 }
 
 void
diff --git a/src/wifi/model/interference-helper.h b/src/wifi/model/interference-helper.h
index 788e26b52..4bdfd909b 100644
--- a/src/wifi/model/interference-helper.h
+++ b/src/wifi/model/interference-helper.h
@@ -43,12 +43,11 @@ public:
     /**
      * Create an Event with the given parameters.
      *
-     * \param size packet size
      * \param txVector TXVECTOR of the packet
      * \param duration duration of the signal
      * \param rxPower the receive power (w)
      */
-    Event (uint32_t size, WifiTxVector txVector, Time duration, double rxPower);
+    Event (WifiTxVector txVector, Time duration, double rxPower);
     ~Event ();
 
     /**
@@ -75,12 +74,6 @@ public:
      * \return the receive power (w)
      */
     double GetRxPowerW (void) const;
-    /**
-     * Return the size of the packet (bytes).
-     *
-     * \return the size of the packet (bytes)
-     */
-    uint32_t GetSize (void) const;
     /**
      * Return the TXVECTOR of the packet.
      *
@@ -96,7 +89,6 @@ public:
 
 
 private:
-    uint32_t m_size; ///< size
     WifiTxVector m_txVector; ///< TXVECTOR
     Time m_startTime; ///< start time
     Time m_endTime; ///< end time
@@ -160,14 +152,13 @@ private:
   /**
    * Add the packet-related signal to interference helper.
    *
-   * \param size packet size
    * \param txVector TXVECTOR of the packet
    * \param duration the duration of the signal
    * \param rxPower receive power (W)
    *
    * \return InterferenceHelper::Event
    */
-  Ptr<InterferenceHelper::Event> Add (uint32_t size, WifiTxVector txVector, Time duration, double rxPower);
+  Ptr<InterferenceHelper::Event> Add (WifiTxVector txVector, Time duration, double rxPower);
 
   /**
    * Add a non-Wifi signal to interference helper.
diff --git a/src/wifi/model/wifi-phy.cc b/src/wifi/model/wifi-phy.cc
index 35167888f..40377c89e 100644
--- a/src/wifi/model/wifi-phy.cc
+++ b/src/wifi/model/wifi-phy.cc
@@ -2385,8 +2385,7 @@ WifiPhy::StartReceivePreambleAndHeader (Ptr<Packet> packet, double rxPowerW, Tim
   Time preambleAndHeaderDuration = CalculatePlcpPreambleAndHeaderDuration (txVector);
 
   Ptr<InterferenceHelper::Event> event;
-  event = m_interference.Add (packet->GetSize (),
-                              txVector,
+  event = m_interference.Add (txVector,
                               rxDuration,
                               rxPowerW);