Abstract: A method for transmission to a receiver of a geographic coordinate ? of a transmitter positioned in a spherical coordinate system ?, ?, at least a portion of one hemisphere of the Earth's sphere being divided into N sections each bounded by a minimum ? and a maximum ?, each section being subdivided into X cells each bounded by a minimum ? and a maximum ?, X varying depending on the section, includes at least the following steps: partitioning all of the latitude sections into M+1 classes, M sections being interspersed between two sections of the same class; transmitting, in one and the same message, the coordinate ? of the transmitter referenced relative to the cell in which the transmitter is located and the class of the latitude section in which the transmitter is located, the range of the receiver being at the most equal to the width of a cell along the axis of variation of the coordinate ?.

Abstract: Method making it possible to reconstruct a first signal taking the form of a series of pulses of width T, characterized in that it comprises a step in which a delay ? fixed with respect to the first signal to be reconstructed is introduced into a second signal having a sinusoidal shape and in that the porches of width T of the first signal at an instant t are substituted with portions of sinusoid of the second delayed sinusoidal signal corresponding to an instant t?1 so as to reconstruct a signal having a sinusoidal shape.

Abstract: A method for transmission to a receiver of a geographic coordinate ? of a transmitter positioned in a spherical coordinate system ?, ?, at least a portion of one hemisphere of the Earth's sphere being divided into N sections each bounded by a minimum ? and a maximum ?, each section being subdivided into X cells each bounded by a minimum ? and a maximum ?, X varying depending on the section, includes at least the following steps: partitioning all of the latitude sections into M+1 classes, M sections being interspersed between two sections of the same class; transmitting, in one and the same message, the coordinate ? of the transmitter referenced relative to the cell in which the transmitter is located and the class of the latitude section in which the transmitter is located, the range of the receiver being at the most equal to the width of a cell along the axis of variation of the coordinate ?.

Abstract: Method making it possible to reconstruct a first signal taking the form of a series of pulses of width T, characterized in that it comprises a step in which a delay ? fixed with respect to the first signal to be reconstructed is introduced into a second signal having a sinusoidal shape and in that the porches of width T of the first signal at an instant t are substituted with portions of sinusoid of the second delayed sinusoidal signal corresponding to an instant t?1 so as to reconstruct a signal having a sinusoidal shape.