Method of and apparatus for message communication on Loran-C navigational signal broadcasts and the like with reduced navigation errors

摘要

In a Loran-C message communication system a method of obviating errors in navigation locking caused by sampling reception at the conventional symmetrical pulse modulation time intervals in advance of and in delay from the normal transmission interval, through rendering the pulse modulation assymetrical to a degree that compensates for different cycle amplitudes at sampling points above and below the desired sixth zero crossing used for navigation position determination.