Radiopositioning, 3

Two fixed shore stations A and https://www.w3.org/1998/Math/MathML" display="inline"> A ' with known coordinates transmit impulses at regular intervals. To simplify this case, it is supposed here that the signals are synchronised. If A and https://www.w3.org/1998/Math/MathML" display="inline"> A ' transmit at the same instant t , on board the receivers receive the impulses at time TA and TA’ but only the difference TA’ - TA is used. A diagram illustrates how waves behave when they encounter a boundary and are refracted. The land area is depicted on the left side, shaded with dots. Point A is located at the boundary between the land and the other medium. Several curved lines originate from point A and travel through the medium, representing the wave fronts. These lines are refracted as they pass through the boundary and continue to propagate outward. Point M is located at the outer edge of the diagram, indicating a point where the waves have travelled. https://www.w3.org/1999/xlink" xlink:href=" https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781003761020/e10523ab-dbe3-4c4f-8f3e-863ae3683950/content/pg185_1.tif "/> https://www.w3.org/1998/Math/MathML" display="block"> At M : T A = t + MA V T A ' = t + M A ' V where T A ' - T A = M A ' - MA V and MA - M A ' = V T A - T A '