STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

936 Drilling and Well Completions
Clock
24Hz
TiWU
____)
Clock bit " n n
I
Figure 4-247. Principle of the continuous wave system: (a) sketch of the
siren and electronic block diagram; (b) principle of the coding by phase shift
keying. (Courtesy Anadrill [106].)
binary weight
32 64 120 256 512 3
0 1 1 0 1 0 0 0 0 0
A # % m , V M M M n l * ~ ~
I
. I .... f ,T;
le
I 1 frame *I
I
I (16 words) I
(1280 cycla3 - 106.7 secoiids)
Figure 4-248. Example of a frame of data transmitted by the continuous
wave system. (Courtesy Anadrill [106].)