Final answer:
The magnitude of the incident electric field can be calculated using the power transferred to the load, and the conductance part of the antenna's input impedance. The given impedance and power allow for the determination of the required electric field intensity for 1 MW power transfer.
Step-by-step explanation:
The student is asking about the magnitude of the incident electric field (ℓEℓ) required to transfer a power of 1 megawatt (MW) to a load when a 1.5λ dipole antenna is used for reception at a frequency of 600 MHz. The input impedance of the antenna is given as Za=105+j20Ω, and it is connected to a load with the conjugate of Za, that is ZL=Za*. This setup ensures maximum power transfer to the load.
According to the maximum power transfer theorem, the power transferred to the load when the load impedance matches the conjugate of the source impedance is given by:
P = ℓE²·G
Where P is the power transferred (1 MW), ℓE² is the magnitude of the incident electric field squared, and G is the conductance part of the input impedance. Calculating ℓE² from this equation allows us to find the magnitude of the incident electric field.
Note that the detailed calculation involves using the impedance value to determine the conductance, which here would be the real part of Za (105 Ω) inverted. The reactive part (j20 Ω) does not dissipate power but influences the phase of the current. Then, insert the given power value (1 MW) to solve for the electric field intensity needed to achieve this power transfer.