问题
I need to reduce the coverage area of communication between vehicles. Should I reduce values of these parameters in omnetpp.ini?
*.**.nic.phy80211p.sensitivity = -89dBm
*.**.nic.phy80211p.maxTXPower = 10mW
*.**.nic.phy80211p.thermalNoise = -110dBm
If not, which parameters can I modify please?
回答1:
If by coverage area you mean communication range, the short answer is yes, you can modify these parameters to reduce the communication range (which I'd probably do by lowering the maximum transmission power). Alternatively, you can change the channel properties (in config.xml) by adding a corresponding analog model that has the behavior you're looking for. I recommend having a look at the Two-Ray Interference model and the Obstacle Shadowing model, which are part of VEINS.
回答2:
In the current Veins version (i.e. 4.5) you can also reduce the maxInterfDist of the ConnectionManager which will result in overall less vehicles getting an AirFrame given to their NICs which they then try to decode. However, this only decreases the distance of the best possible communication (i.e. without buildings in LOS, etc.) and not the average distance which usually is way smaller due to fading effects and buildings.
回答3:
in my opinion, the maxTXPower and maxInterfDist do not affect the coverage area between vehicles. You should modify the "..nic.mac1609_4.txPower" and "..nic.phy80211p.sensitivity". For a better understanding, you may check the answer from Christoph Sommer in this thread: how to set the transmission range of a node under Veins 2.0?
来源：https://stackoverflow.com/questions/43933125/reduce-the-coverage-area-between-vehicles