问题
I am wondering if the theoretical maximum transmission range under Omnet++ (veins framework) is the same as the maximum interference distance.
I want to confirm some calculations done before by another person, Last one concludes that the transmission range is equal to :
- 127m for Txpower = -80dbm & sensitivity = 10mW
- 300m for Txpower = -80dbm & sensitivity = 15.5mW
- 1000m for Txpower = -94dbm & sensitivity = 20mW
For all calculations: path loss coeffcient alpha = 2 & frequency = 5890Mhz
On my side, I get respectively 127m, 159m and 907m. I am not able to know why to much difference. I use the free space path loss formula.
Can someone confirm to me these result ?
回答1:
You are correct: if a frame's receive power in Veins 3 is under the sensitivity threshold, the packet can never be decoded (independent of its received SINR).
The free space path loss formula used in Veins 3 is:
For a transmit power of 20 mW and a sensitivity threshold of -94 dBm (I am assuming that this is just a typo in your question), the distance where the received power drops under the sensitivity threshold can be calculated to be (roughly) 907 meters.
Since you specifically asked for the maximum interference range, though, please note that the transmit power can be selected for each frame and the sensitivity threshold can be configured for each radio. They are therefore not used for calculating the maximum interference range (the distance where a sender is deemed so far away that it will not even contribute interference). This distance is calculated independently by the global ConnectionManager module, whose job it is to deliver "ongoing radio transmission" events to all affected modules. It uses a completely separate (global) set of parameters to calculate this range.
来源：https://stackoverflow.com/questions/31712578/maximum-transmission-range-vs-maximum-interference-distance