enabled cellular networks from a general threshold-based perspective. Specifically, a
mobile user equipment (TIE) transmits in D2D mode if the received signal strength (RSS)
from the nearest base station (BS) is less than a specified threshold β≥ 0; otherwise, it
connects to the nearest BS and transmits in cellular mode. The RSS-threshold-based setting
is general in the sense that by varying β from β= 0 to β=∞, the network accordingly evolves …