GNSS-based real-time high-precision wave measurement method and apparatus

A GNSS-based real-time high-precision wave measurement method, the method comprising the following steps:

• (1) constituting a wave measurement apparatus by using a sea surface carrier collecting high-frequency GNSS positioning electromagnetic wave signals in real time, converting the high-frequency GNSS positioning electromagnetic wave signals into phases, pseudo-ranges, Doppler frequency shift observations and broadcast ephemerides and sending them to a processor of the wave measurement apparatus;
• (2) solving horizontal and vertical three-dimensional motion speeds of the sea surface carrier in real time by use of an established phase observation epoch differential equation using the broadcast ephemeris and in consideration with the processing of error terms;
• (3) repeating steps (1)-(2) for 10 to 20 minutes to reach a certain amount of data until the initialization of wave measurement is completed;
• (4) solving the horizontal and vertical three-dimensional motion speeds of the sea surface carrier at each epoch in real time, repeating steps (1)-(3) by using a sliding time window method to integrate the vertical motion speed for 10-30 minutes and remove a trend term caused by the system error and tide so as to obtain time-dependent vertical displacement change information, and then solving wave element information;
• alternatively, calculating the cross spectrum by means of the cross-correlation function through solved vertical, east-west and north-south speeds of the wave measurement apparatus, followed by solving the direction spectrum and the frequency spectrum by means of the direction spectrum analysis method, and then solving the wave height, the period and the wave direction;
• and
• (5) locally storing the wave element information during these sliding time window periods, that is calculated in real time, in a buoy, or periodically returning the wave element information by means of real-time communication.