  Due to Unmanned aerial vehicles (UAVs) limitations in processing power and
battery lifetime. The tethered UAV (TUAV) offers an attractive approach to
answer these shortcomings. Since a tethered connected to UAV is one potential
energy solution to provide a stable power supply that connects to the ground
would achieve impressive performances in smart environments and disaster
recovery. The proposed solution is intended to provide stable energy and
increase the coverage area of TUAV for smart environments and disaster
recovery. This paper proposed that the tethered connected to UAV will provide
the continuous supply and exchange the data with ground terminals. Besides the
adjustable tether length, elevation angels act to increase the hovering region,
leading to the scalability of coverage in many applications. Moreover, the
power consumption and transmission the distance while achieving a trade-off
between the hovering and coverage probabilities. The simulation results
demonstrate efficient performance in terms of line-of-sight probability, path
loss, and coverage probability for scalability coverage smart environments and
disaster recovery scenarios. Furthermore, maximum coverage probability is
achieved versus increased tethered length because of the gain and fly over a
region of maximum tethered.
