Transient Constant Area Surface and Downhole Wave Models - Measurement While Drilling Signal Analysis, Optimization and Design - page 107

Figure 4.1h . 24 Hz low frequency carrier wave with phase shift keying.
4.1.6 Runs 4 and 5. Phase-shift keying or PSK, very high data rate.
In this example, we consider a high data rate 48 Hz carrier wave not
presently used commercially by any service company.
C CASE 3. PHASE-SHIFTING (F = FREQUENCY IN HERTZ)
PI = 3.14159
A = 0.25
F = 48.
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) G = +A*SIN(2.*PI*F*T)
IF(T.GE.PERIOD.AND.T.LE.2.*PERIOD) G = -A*SIN(2.*PI*F*T)
IF(T. GE.2.*PERIOD) G = 0.
x Roundtrip delay = 0.02 sec
x Sampling time = 0.00025 sec
Figure 4.1i . New high data rate 48 Hz carrier with PSK.