Equation Icon  ( ( ) ( ) ) a3 = ra1 exp(− i2ϕ0 ) 1 + im-exp − i(ωst + φs) + im-exp i(ωst + φs) ( 2 ( 2) = ra1 exp(− i2ϕ0 ) 1 + m-exp − i(ωst + φs − π ∕2) (63 ) ( 2 )) + m2-exp i(ωst + φs + π ∕2) .