A Truncated Waveguide Fed by a Microstrip as a Radiating Element for High-Performance Automotive Anticollision Radars

Figure 6

Element excitation (a) and phase of the input impedance (b) versus 𝑊_𝑆 for different values of the dielectric permittivity 𝜀_rd (see Figure 2), 𝐿_𝑆=2 mm, and ℎ_𝑑=1.2 mm.

(a)

(b)