Every antenna datasheet lists directivity. You must understand how length changes gain. What the manual teaches: The graph of directivity vs. ( L/\lambda ).
Solving inhomogeneous vector potential wave equations and far-field radiation problems. antenna theory analysis and design solution manual pdf
Use the manual as a tutor , not a ghostwriter . Attempt the problem for three hours. Then, open the solution to check your third step. If you found a different path, explore why. Every antenna datasheet lists directivity