car node can't receive wave short messages - omnet++

Question

I have a scenario that includes a single car node and a single RSU node. the car sends a beacon message every 1s. when the RSU receives a beacon message, it should reply back to the sender (the car) with a wave short message.
I create a WSM once the RSU receives a BSM, and I set the receiver's ID to the bsm sender ID (as I want the RSU to send the message only to a specific node). the problem is that the wsm in never received by the car (onWSM function is never called).
here is the code:
void RSUApp::onBSM(BasicSafetyMessage* bsm)
{
/*this fn is called when rsu receives a beacon*/
/*after receiving beacon, send the value of the current speed*/
WaveShortMessage* msg= new WaveShortMessage("speed");
msg->setSenderAddress(this->myId);
msg->setWsmData(std::to_string(this->currentSpeed).c_str());
int Id = bsm->getSenderAddress();
populateWSM(msg,Id,0);
sendDown(msg);
}
when I replace the receiver's ID by -1 (send broadcast message instead of sending to specific node), the car APP can handle the WSM without problems.
populateWSM(msg,-1,0);
I am using veins 4.7 and this is the ini file contents:
*.rsu[0].mobility.x = 500
*.rsu[0].mobility.y = 50
*.rsu[0].mobility.z = 3
*.rsu[*].applType = "iteration6.src.RSUApp"
*.rsu[*].appl.headerLength = 80 bit
*.rsu[*].appl.sendBeacons = false
*.rsu[*].appl.dataOnSch = false
*.connectionManager.sendDirect = true
*.connectionManager.maxInterfDist = 2600m
*.connectionManager.drawMaxIntfDist = true
*.**.nic.mac1609_4.useServiceChannel = false
*.**.nic.mac1609_4.txPower = 20mW
*.**.nic.mac1609_4.bitrate = 6Mbps
*.**.nic.phy80211p.sensitivity = -89dBm
*.**.nic.phy80211p.useThermalNoise = true
*.**.nic.phy80211p.thermalNoise = -110dBm
*.**.nic.phy80211p.decider = xmldoc("config.xml")
*.**.nic.phy80211p.analogueModels = xmldoc("config.xml")
*.**.nic.phy80211p.usePropagationDelay = true
*.node[*].applType = "iteration6.src.carApp"
*.node[*].appl.headerLength = 80 bit
*.node[*].appl.sendBeacons = true
*.node[*].appl.dataOnSch = false
*.node[*].appl.beaconInterval = 1s
can anyone help me with that problem?

Answer 1

It seems like you are using the wrong id for the recipient. Instead of
int Id = bsm->getSenderModuleId();
you should rather use
int Id = bsm->getSenderAddress();
This should do the trick.
See the following sources for more details:
WaveShortMessage
populateWSM

Answer 2

The newer version of veins returns MAC based myId while previous versions returned Module Identifier. This needs to be kept in mind while assigning addresses to nodes.