diff --git a/src/wifi/model/ideal-wifi-manager.cc b/src/wifi/model/ideal-wifi-manager.cc
index 14fe4514c..69228b341 100644
--- a/src/wifi/model/ideal-wifi-manager.cc
+++ b/src/wifi/model/ideal-wifi-manager.cc
@@ -329,7 +329,7 @@ IdealWifiManager::DoGetDataTxVector (WifiRemoteStation *st)
                   // Derive NSS from the MCS index. There is a different mode for each possible NSS value.
                   uint8_t nss = (mode.GetMcsValue () / 8) + 1;
                   txVector.SetNss (nss);
-                  if (WifiPhy::IsValidTxVector (txVector) == false
+                  if (!txVector.IsValid ()
                       || nss > std::min (GetMaxNumberOfTransmitStreams (), GetNumberOfSupportedStreams (st)))
                     {
                       NS_LOG_DEBUG ("Skipping mode " << mode.GetUniqueName () <<
@@ -373,7 +373,7 @@ IdealWifiManager::DoGetDataTxVector (WifiRemoteStation *st)
                   for (uint8_t nss = 1; nss <= std::min (GetMaxNumberOfTransmitStreams (), GetNumberOfSupportedStreams (station)); nss++)
                     {
                       txVector.SetNss (nss);
-                      if (WifiPhy::IsValidTxVector (txVector) == false)
+                      if (!txVector.IsValid ())
                         {
                           NS_LOG_DEBUG ("Skipping mode " << mode.GetUniqueName () <<
                                         " nss " << (uint16_t) nss << " width " <<
@@ -412,7 +412,7 @@ IdealWifiManager::DoGetDataTxVector (WifiRemoteStation *st)
                   for (uint8_t nss = 1; nss <= GetNumberOfSupportedStreams (station); nss++)
                     {
                       txVector.SetNss (nss);
-                      if (WifiPhy::IsValidTxVector (txVector) == false)
+                      if (!txVector.IsValid ())
                         {
                           NS_LOG_DEBUG ("Skipping mode " << mode.GetUniqueName () <<
                                         " nss " << (uint16_t) nss << " width " <<
diff --git a/src/wifi/model/minstrel-ht-wifi-manager.cc b/src/wifi/model/minstrel-ht-wifi-manager.cc
index 2740e361d..6dc4ff060 100644
--- a/src/wifi/model/minstrel-ht-wifi-manager.cc
+++ b/src/wifi/model/minstrel-ht-wifi-manager.cc
@@ -316,12 +316,11 @@ bool
 MinstrelHtWifiManager::IsValidMcs (Ptr<WifiPhy> phy, uint8_t streams, uint8_t chWidth, WifiMode mode)
 {
   NS_LOG_FUNCTION (this << phy << (uint16_t)streams << (uint16_t)chWidth << mode);
-
   WifiTxVector txvector;
   txvector.SetNss (streams);
   txvector.SetChannelWidth (chWidth);
   txvector.SetMode (mode);
-  return phy->IsValidTxVector (txvector);
+  return txvector.IsValid ();
 }
 
 Time
diff --git a/src/wifi/model/wifi-phy.cc b/src/wifi/model/wifi-phy.cc
index 27f52ed21..be7897302 100644
--- a/src/wifi/model/wifi-phy.cc
+++ b/src/wifi/model/wifi-phy.cc
@@ -3458,42 +3458,6 @@ WifiPhy::GetHeMcs11 ()
   return mcs;
 }
 
-bool
-WifiPhy::IsValidTxVector (WifiTxVector txVector)
-{
-  uint8_t chWidth = txVector.GetChannelWidth ();
-  uint8_t nss = txVector.GetNss ();
-  std::string modeName = txVector.GetMode ().GetUniqueName ();
-
-  if (chWidth == 20)
-    {
-      if (nss != 3 && nss != 6)
-        {
-          return (modeName != "VhtMcs9");
-        }
-    }
-  else if (chWidth == 80)
-    {
-      if (nss == 3 || nss == 7)
-        {
-          return (modeName != "VhtMcs6");
-        }
-      else if (nss == 6)
-        {
-          return (modeName != "VhtMcs9");
-        }
-    }
-  else if (chWidth == 160)
-    {
-      if (nss == 3)
-        {
-          return (modeName != "VhtMcs9");
-        }
-    }
-
-  return true;
-}
-
 bool
 WifiPhy::IsModeSupported (WifiMode mode) const
 {
diff --git a/src/wifi/model/wifi-phy.h b/src/wifi/model/wifi-phy.h
index c81ce348e..9fbc326cd 100644
--- a/src/wifi/model/wifi-phy.h
+++ b/src/wifi/model/wifi-phy.h
@@ -1202,16 +1202,6 @@ public:
    */
   static WifiMode GetHeMcs11 ();
 
-  /**
-   * The standard disallows certain combinations of WifiMode, number of
-   * spatial streams, and channel widths.  This method can be used to
-   * check whether this WifiTxVector contains an invalid combination.
-   *
-   * \param txVector the WifiTxVector to inspect
-   * \return true if the WifiTxVector parameters are allowed by the standard
-   */
-  static bool IsValidTxVector (WifiTxVector txVector);
-
   /**
    * Public method used to fire a PhyTxBegin trace.
    * Implemented for encapsulation purposes.
diff --git a/src/wifi/model/wifi-tx-vector.cc b/src/wifi/model/wifi-tx-vector.cc
index 573f8c5b8..c60391c0c 100644
--- a/src/wifi/model/wifi-tx-vector.cc
+++ b/src/wifi/model/wifi-tx-vector.cc
@@ -207,6 +207,38 @@ WifiTxVector::SetStbc (bool stbc)
   m_stbc = stbc;
 }
 
+bool
+WifiTxVector::IsValid (void) const
+{
+  std::string modeName = m_mode.GetUniqueName ();
+  if (m_channelWidth == 20)
+    {
+      if (m_nss != 3 && m_nss != 6)
+        {
+          return (modeName != "VhtMcs9");
+        }
+    }
+  else if (m_channelWidth == 80)
+    {
+      if (m_nss == 3 || m_nss == 7)
+        {
+          return (modeName != "VhtMcs6");
+        }
+      else if (m_nss == 6)
+        {
+          return (modeName != "VhtMcs9");
+        }
+    }
+  else if (m_channelWidth == 160)
+    {
+      if (m_nss == 3)
+        {
+          return (modeName != "VhtMcs9");
+        }
+    }
+  return true;
+}
+
 std::ostream & operator << ( std::ostream &os, const WifiTxVector &v)
 {
   os << "mode: " << v.GetMode () <<
diff --git a/src/wifi/model/wifi-tx-vector.h b/src/wifi/model/wifi-tx-vector.h
index b21838496..8b6a083e8 100644
--- a/src/wifi/model/wifi-tx-vector.h
+++ b/src/wifi/model/wifi-tx-vector.h
@@ -203,6 +203,14 @@ public:
    * \param stbc enable or disable STBC
    */
   void SetStbc (bool stbc);
+  /**
+   * The standard disallows certain combinations of WifiMode, number of
+   * spatial streams, and channel widths.  This method can be used to
+   * check whether this WifiTxVector contains an invalid combination.
+   *
+   * \return true if the WifiTxVector parameters are allowed by the standard
+   */
+   bool IsValid (void) const;
 
 
 private: