wifi: Add support for non-HT duplicate

src/wifi/model/non-ht/ofdm-phy.cc

@@ -369,14 +369,29 @@ OfdmPhy::GetTxPowerSpectralDensity(double txPowerW, Ptr<const WifiPpdu> ppdu) co
     uint16_t channelWidth = txVector.GetChannelWidth();
     NS_LOG_FUNCTION(this << centerFrequency << channelWidth << txPowerW);
     const auto& txMaskRejectionParams = GetTxMaskRejectionParams();
-    Ptr<SpectrumValue> v = WifiSpectrumValueHelper::CreateOfdmTxPowerSpectralDensity(
-        centerFrequency,
-        channelWidth,
-        txPowerW,
-        GetGuardBandwidth(channelWidth),
-        std::get<0>(txMaskRejectionParams),
-        std::get<1>(txMaskRejectionParams),
-        std::get<2>(txMaskRejectionParams));
+    Ptr<SpectrumValue> v;
+    if (txVector.IsNonHtDuplicate())
+    {
+        v = WifiSpectrumValueHelper::CreateDuplicated20MhzTxPowerSpectralDensity(
+            centerFrequency,
+            channelWidth,
+            txPowerW,
+            GetGuardBandwidth(channelWidth),
+            std::get<0>(txMaskRejectionParams),
+            std::get<1>(txMaskRejectionParams),
+            std::get<2>(txMaskRejectionParams));
+    }
+    else
+    {
+        v = WifiSpectrumValueHelper::CreateOfdmTxPowerSpectralDensity(
+            centerFrequency,
+            channelWidth,
+            txPowerW,
+            GetGuardBandwidth(channelWidth),
+            std::get<0>(txMaskRejectionParams),
+            std::get<1>(txMaskRejectionParams),
+            std::get<2>(txMaskRejectionParams));
+    }
     return v;
 }
 

src/wifi/model/non-ht/ofdm-ppdu.cc

@@ -40,7 +40,7 @@ OfdmPpdu::OfdmPpdu(Ptr<const WifiPsdu> psdu,
                    bool instantiateLSig /* = true */)
     : WifiPpdu(psdu, txVector, txCenterFreq, uid),
       m_band(band),
-      m_channelWidth(txVector.GetChannelWidth())
+      m_channelWidth(txVector.IsNonHtDuplicate() ? 20 : txVector.GetChannelWidth())
 {
     NS_LOG_FUNCTION(this << psdu << txVector << txCenterFreq << band << uid);
     if (instantiateLSig)

src/wifi/model/wifi-tx-vector.cc

@@ -253,6 +253,13 @@ WifiTxVector::IsLdpc() const
     return m_ldpc;
 }
 
+bool
+WifiTxVector::IsNonHtDuplicate() const
+{
+    return ((m_channelWidth >= 40) && !IsMu() &&
+            (GetMode().GetModulationClass() < WIFI_MOD_CLASS_HT));
+}
+
 void
 WifiTxVector::SetMode(WifiMode mode)
 {

src/wifi/model/wifi-tx-vector.h

@@ -269,13 +269,13 @@ class WifiTxVector
     /**
      * Checks whether the PSDU contains A-MPDU.
      * \returns true if this PSDU has A-MPDU aggregation,
-     *          false otherwise.
+     *          false otherwise
      */
     bool IsAggregation() const;
     /**
      * Sets if PSDU contains A-MPDU.
      *
-     * \param aggregation whether the PSDU contains A-MPDU or not.
+     * \param aggregation whether the PSDU contains A-MPDU or not
      */
     void SetAggregation(bool aggregation);
     /**
@@ -304,6 +304,12 @@ class WifiTxVector
      * \param ldpc enable or disable LDPC
      */
     void SetLdpc(bool ldpc);
+    /**
+     * Checks whether this TXVECTOR corresponds to a non-HT duplicate.
+     * \returns true if this TXVECTOR corresponds to a non-HT duplicate,
+     *          false otherwise.
+     */
+    bool IsNonHtDuplicate() const;
     /**
      * Set the BSS color
      * \param color the BSS color