The range/cell size of the eNB is not fixed in NetSim. This would vary based on
1. eNB Transmit power
2. Wireless Channel Loses (Pathloss, Fading, Shadowing)
A UE can decode a signal from the eNB when,
SNR > Threshold (this threshold depends on transmission mode index, available in CQI_SNR_TABLE in LTE.g)
SNR = Rx Power / Noise
Rx Power = Tx Power + Tx Gain + Rx Gain - PL1m - 10 Log (d)^n
By default, the Tx Gain & Rx Gain are zero, and PL1m = 32 dB in LTE. The value of Tx power and n (path loss exponent) depends on what is set by the user in NetSim GUI.
Thus one can solve for d, and find out the range of an LTE eNB. This function is available in fn_NetSim_LTE_CalculateRxPower () in LTE_Phy.c.
The other option is to progressively move the UE farther and farther from the eNB till a very low value of application throughput is got.
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