On Mar 30, 10:04 pm, Cecil Moore wrote:
Keith Dysart wrote:
Ptotal = P1 + P2 + 2*SQRT(P1*P2)cos(A)

Curiosity question: Which of the two possible values for
the square root did you use? Elaborate on the reasons
for your choice?

Probably should be written 2*|SQRT(P1*P2)|*cos(A) to
satisfy the purists. The sign of the interference
term must match the type of interference which is
determined by the sign of cos(A).

More curiousity: Can P1 and P2 have different signs, that is,
the power is going in different directions? If so, how does the
resulting complex SQRT work into the result?

....Keith