The invention relates to a
tracking system and method comprising: a first and second tracking units comprising a
satellite signal receiver, a
microprocessor, a
radio frequency (RF)
transmitter and
receiver; and an indicator means; and in which upon activation of the first unit, the first unit
satellite signal receiver is arranged to receive
satellite signals and to determine a location of the first unit. The first unit
microprocessor is arranged in operation to receive the location from the first unit satellite
signal receiver and generate a first unit location signal in dependence upon said location; and the first unit RF
transmitter is arranged to transmit said signal; the second unit is arranged to receive satellite signals and calculate a second unit location; the second unit
microprocessor is arranged in operation to receive the second unit location from the second unit satellite receiver. The second unit RF receiver is arranged to receive said first unit location signal; and the second unit microprocessor is arranged upon
receipt of said first unit location signal to determine the first unit location; and determine a bearing and distance in dependence upon the first unit location and the second unit location; and indicate said bearing and distance on said second unit indicator means. The first tracking unit also includes a
line of sight obstruction detecting means for detecting the presence of nearby obstructions, a height position determining means for determining the relative height of the first tracking unit, wherein the microprocessor includes means of calculating, with reference to a time source, an optimum communications window to transmit and receive an RF signal in the future, based on the detected nearby obstructions, if any, the height position data, and calculated predicted values for the
wave height and period, and sends an instruction to the RF
transmitter to transmit a signal in the optimum communications window.