Final answer:
The question is about determining the reflection coefficient for a half-wavelength dipole antenna connected to a transmission line with known impedance. the reflection coefficient's magnitude is approximately 0.0135 and the phase is -180 degrees, assuming a typical 73-ohm impedance for the dipole.
Step-by-step explanation:
The student's question pertains to antenna theory in physics, specifically to the concept of a reflection coefficient for a half-wavelength dipole antenna connected to a transmission line. However, to determine the reflection coefficient, additional information is required, such as the impedance of the antenna itself. Typically, a half-wavelength dipole has an impedance of about 73 ohms in free space. The reflection coefficient (Γ) is determined using the formula:
Γ = (Z_{L} - Z_{0}) / (Z_{L} + Z_{0})
Where Z_{L} is the load impedance (antenna impedance) and Z_{0} is the characteristic impedance of the transmission line. Assuming the antenna's impedance is 73 ohms, the reflection coefficient would be calculated as follows:
Γ = (73 - 75) / (73 + 75) = -2 / 148 ≈ -0.0135
The magnitude of the reflection coefficient is the absolute value, which is approximately 0.0135. Since the reflection is negative, that indicates a 180-degree phase change. Thus, the phase in degrees of the reflection coefficient is -180 degrees.