Table 4-2.—Tone Library
* There is no bit location associated with the 605-Hz Doppler tone or the 2,915 Hz tone when used as the Sync tone
Figure 4-14.—Link-11 data phase shift encoding.
Each of these angles marks the center of a
quadrant, as shown in figure 4-14. Each 90-degree
quadrant is assigned a two-bit binary value. Any
phase difference falling within that quadrant
represents that binary value. This system of data
encoding can tolerate an error in the prescribed phase
shift of up to ±44 degrees before a single bit error will
occur. An error in phase shift that is greater than 45
degrees, but less than 135 degrees, will cause the
phase angle to fall into an adjacent quadrant. Notice
that the values are assigned to each quadrant in such
a way that if a phase shift error occurs, that only one
bit error will be introduced as long as the quadrant
into which it falls is adjacent to the target quadrant.
4-12
