Mobile path loss characteristics for low base station antenna height in different forest densities

This paper presents studies of propagation in a suburban forest based on a measurement campaign at a frequency of 1.8 GHz. We investigated how tree density affected path loss-distance and the fast fading characteristic depending on the base tree size and base station antenna height in a range of 3, 4, and 5 m above ground while the receiving antenna height was fixed at 1.8 m above ground. The path loss exponent is found that to average 3.8, 3.7 and 2.2 for the measurement areas of high, medium, and low densities respectively. The high density area with low tree heights provides maximum path loss exponents. Path loss in the same density area depends on the number of trees in the direct path between the transmitter and the receiver. The measurement of signal variation shows that a multi-path contribution becomes more significant as the base station antenna is raised.