Transient Constant Area Surface and Downhole Wave Models - Measurement While Drilling Signal Analysis, Optimization and Design - page 131

C CASE 2
A = 20.0
R = 100.0
SIGNAL = A*(TANH(R*(T-0.100))-TANH(R*(T-0.101)))/2.
Figure 4.5c . Higher data rate, faster valve action.
4.5.7 Run 3. PSK example, 12 Hz frequency.
Here we consider an example in phase-shift-keying, assuming a carrier
frequency of 12 Hz. The time delay between pulser and bit is 0.01 sec, same as
the sampling time. The pulse description appears immediately below.
C CASE 3. PHASE-SHIFTING (F = FREQUENCY IN HERTZ)
PI = 3.14159
A = 0.25
F = 12.
C G = A*SIN(2.*PI*F*T)
C Means 2*PI*F cycles in 2*PI secs, or F cycles per sec, F is Hz.
C One cycle requires time PERIOD = 1./F
PERIOD = 1./F
IF(T.GE.0.0. AND.T.LE. PERIOD) SIGNAL = +A*SIN(2.*PI*F*T)
IF(T.GE.PERIOD.AND.T.LE.2.*PERIOD) SIGNAL = -A*SIN(2.*PI*F*T)
IF(T. GE.2.*PERIOD) SIGNAL = 0.
Figure 4.5d . PSK example, 12 Hz frequency.