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In this paper, the transport characteristics of gold/silver mixed chain nanostructures with different proportions of infinite length in the range of 270-810 nm are studied, and the corresponding band gap characteristics and other transport characteristics are analyzed. We introduced an analytical model to determine the complex dielectric constant of an arbitrary composition Au-Ag alloy, and combined this with the experimental data to study the propagation characteristics of the infinitelength gold-silver mixed-chain nanostructures with various compositions. As the gold content exceeds Au : Ag (1 : 2), the coupling coefficient between the forward and reverse waves becomes smaller, and the reverse wave cannot provide enough energy to transfer to the forward wave. The scattering ability of the scattering unit weakens; the frequency range of the propagation state widens; and it exhibits good propagation characteristics. By gradually increasing the proportion of metal in the alloy, we can explore the variation of the propagation characteristics of the alloy. At present, the change of metal propagation characteristics has not been studied from this point, so we found for the first time that frequency modulation can be realized through this method (regulating the attenuation or cutoff frequency range, namely the band gap range). We also studied a cylindrical finite array chain composed of 40 nanorods under five types of experimental data and discussed the wave guiding ability of the finite array chain under the excitation of a plane wave of a specific wavelength.

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In this letter, a broadband proximity coupled millimeter-wave microstrip array antenna is presented for automotive radar applications. The antenna array consists of a microstrip line and a series of trapezoidal radiating elements that are periodically arranged on both sides of the microstrip line, at intervals of about half the guided-wavelength. The introduction of the trapezoidal radiating patch enhances the excitation coupling while suppressing out-of-band frequencies, and it has a wider impedance bandwidth than the rectangular patch. In the design of proposed antenna, the normalized resistance of the trapezoidal radiating element is controlled by adjusting the gap with the microstrip line, so that a low-sidelobe level (SLL) can be achieved. Taking the 77-81 GHz frequency band allocated to automotive radar applications as an example, a 1 × 16 linear array is designed and fabricated. The measured SLL is better than −20 dB. The measured gain of 1 × 16 array is higher than 15 dBi over the operating frequency range of 77-81 GHz. The 1 × 16 linear array can achieve an impedance bandwidth of 7.6% (75.6-81.6 GHz).