wifi: Call WifiPpdu::Copy only for APs expecting HE TB PPDUs

src/wifi/model/he/he-phy.cc

@@ -1773,6 +1773,20 @@ HePhy::CanStartRx(Ptr<const WifiPpdu> ppdu) const
     return PhyEntity::CanStartRx(ppdu);
 }
 
+Ptr<const WifiPpdu>
+HePhy::GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu)
+{
+    // We only copy if the AP that is expecting a HE TB PPDU, since the content
+    // of the TXVECTOR is reconstructed from the TRIGVECTOR, hence the other RX
+    // PHYs should not have this information.
+    if ((ppdu->GetType() == WIFI_PPDU_TYPE_UL_MU) &&
+        (Simulator::Now() <= m_trigVectorExpirationTime))
+    {
+        return ppdu->Copy();
+    }
+    return PhyEntity::GetRxPpduFromTxPpdu(ppdu);
+}
+
 } // namespace ns3
 
 namespace

src/wifi/model/he/he-phy.h

@@ -115,6 +115,7 @@ class HePhy : public VhtPhy
                        Time duration,
                        WifiChannelListType channelType) override;
     bool CanStartRx(Ptr<const WifiPpdu> ppdu) const override;
+    Ptr<const WifiPpdu> GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu) override;
 
     /**
      * \return the BSS color of this PHY.

src/wifi/model/phy-entity.cc

@@ -1352,4 +1352,10 @@ PhyEntity::CanStartRx(Ptr<const WifiPpdu> ppdu) const
     return ppdu->DoesCoverChannel(p20MinFreq, p20MaxFreq);
 }
 
+Ptr<const WifiPpdu>
+PhyEntity::GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu)
+{
+    return ppdu;
+}
+
 } // namespace ns3

src/wifi/model/phy-entity.h

@@ -527,6 +527,17 @@ class PhyEntity : public SimpleRefCount<PhyEntity>
     virtual double GetCcaThreshold(const Ptr<const WifiPpdu> ppdu,
                                    WifiChannelListType channelType) const;
 
+    /**
+     * The WifiPpdu from the TX PHY is received by each RX PHY attached to the same channel.
+     * By default and for performance reasons, all RX PHYs will work on the same WifiPpdu instance
+     * from TX instead of a copy of it. Child classes can change that behavior and do a copy and/or
+     * change the content of the parameters stored in WifiPpdu.
+     *
+     * \param ppdu the WifiPpdu transmitted by the TX PHY
+     * \return the WifiPpdu to be used by the RX PHY
+     */
+    virtual Ptr<const WifiPpdu> GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu);
+
   protected:
     /**
      * A map of PPDU field elements per preamble type.

src/wifi/model/spectrum-wifi-phy.cc

@@ -392,7 +392,7 @@ SpectrumWifiPhy::StartRx(Ptr<SpectrumSignalParameters> rxParams)
     // Do no further processing if signal is too weak
     // Current implementation assumes constant RX power over the PPDU duration
     // Compare received TX power per MHz to normalized RX sensitivity
-    const auto& ppdu = wifiRxParams->ppdu;
+    const auto& ppdu = GetRxPpduFromTxPpdu(wifiRxParams->ppdu);
     const auto& txVector = ppdu->GetTxVector();
     uint16_t txWidth = ppdu->GetTransmissionChannelWidth();
     if (totalRxPowerW < DbmToW(GetRxSensitivity()) * (txWidth / 20.0))
@@ -418,6 +418,12 @@ SpectrumWifiPhy::StartRx(Ptr<SpectrumSignalParameters> rxParams)
     StartReceivePreamble(ppdu, rxPowerW, rxDuration);
 }
 
+Ptr<const WifiPpdu>
+SpectrumWifiPhy::GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu)
+{
+    return GetLatestPhyEntity()->GetRxPpduFromTxPpdu(ppdu);
+}
+
 Ptr<Object>
 SpectrumWifiPhy::GetAntenna() const
 {

src/wifi/model/spectrum-wifi-phy.h

@@ -152,6 +152,14 @@ class SpectrumWifiPhy : public WifiPhy
      */
     void Transmit(Ptr<WifiSpectrumSignalParameters> txParams);
 
+    /**
+     * Determine the WifiPpdu to be used by the RX PHY based on the WifiPpdu sent by the TX PHY.
+     *
+     * \param ppdu the WifiPpdu transmitted by the TX PHY
+     * \return the WifiPpdu to be used by the RX PHY
+     */
+    Ptr<const WifiPpdu> GetRxPpduFromTxPpdu(Ptr<const WifiPpdu> ppdu);
+
   protected:
     void DoDispose() override;
     void DoInitialize() override;