networking - Signal is too weak ? (Omnet++& Mixim) -


what causes of warning "signal weak" in output of network simulation ?

currently, i'm using omnet++ 4.2, mixim 2.2 , veins 2.0-rc1

i know related many factors including tworayinterferance model, in order understand underlying cause, have several hypothesis :

  1. the distance between 2 nodes equal or exceed transmission range, signal weak correctly interpreted.

  2. channel switch of 802.11p (sch vs cch) occur juste before such warning, possible switch causes such thing ? (i read channel switch causes time guard, channel considered busy)

  3. collision of 2 packets, scheduled @ same time : csma/ca broadcast mode of 802.11p, air frames directly send if channel detected idle, if 2 nodes decide send air frames @ same time, collision can occur , produce "signal weak" warning

can confirm i'm suggesting ?

many thanks,

i commenting future reference: "signal weak" in veins 1 referred signals received weaker sensitivity threshold (see code). veins 2 onwards, debug message replaced more verbose "packet not detected card. power under sensitivity threshold" (see code)


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