Author(s)

Xuehui Cui, Wei Xiang

Corresponding Author

Wei Xiang

ABSTRACT

For the purpose of reducing loss in signal propagation, this paper calculates numbers of hops on the surface of ground and sea and proposes methods for minimizing the loss of the signal and remain the ship in communication using the same multi-hop path in the process of multi-hop propagation mode of high-frequency signals. Four mathematical models are proposed to determine the loss of the signal in the process of propagation, parallel reflection model, calm ocean surface reflection model, turbulent ocean sphere reflection model and ground reflection model. The influential factors of signal is divided into noise and attenuation. Furthermore, the noise is divided into three categories, atmospheric radio noise, artificial radio noise, and cosmic noise. Attenuation is divided into free space propagation loss, ionospheric absorption loss, reflection loss, and extra system loss. This paper studies the shipboard receiver moving on a turbulent ocean range of the receiver on its received signal and defines the maximum communication time and communication area so as to calculate the holding time of the multi-hop path. It can be found that the value of the change of emission point incident angle per second on average. Thus, it can be ensured that the ship is always in communication with the transmitting station during the traveling process.

KEYWORDS

Maritime communication, shortwave, ionosphere, reflection intensity, free space.