Investigation of negative refraction property for a compact LHM with broad bandwidth

In this paper, a compact left-handed metamaterial (LHM) with miniaturized unit cell and broad bandwidth is proposed. By optimization design, its bandwidth is up to 2.6 GHz, and the smallest electrical length of the LHM unit cell is only 0.1 of the working wavelength at the lowest operating frequency where the LHM is available. The transmission parameters (S₂₁) are given for the scattering of the normally incident plane wave from the LHM with both the ENG (epsilon-negative) part and MNG (Mu-negative) part, LHM with only the ENG part and LHM with only the MNG part. Results show that there is a pass-band only for the LHM with both ENG and MNG within 9.2 GHz-11.8 GHz. In addition, the negative refraction characteristic of the wedge-shaped LHM are investigated using full-wave simulation, it is shown that the designed LHM exhibits negative refraction in a broadband of 9.2 GHz-11.8 GHz range, and the existence of the LHM is proven. The designed compact LHM provides a good opportunity to design and fabricate devices or components, which are used in MW measurements frequently, with better performance such as miniaturized cavity resonator, miniaturized filter, and antenna with better directionality and so on.