Electrically Small, Metamaterial-inspired Monopole Antennas for WLAN Applications

We present three designs of electrically small, metamaterial-inspired antennas for WLAN applications. Each antenna consists of a different metamaterial unit cell such as the complementary split ring resonator (CSRR), double meander cell, and electric-LC (ELC) resonator that is transformed into a monopole-like structure with subwavelength dimensions. The monopoles are fed through a standard microstrip line, where a small ground plane is included as well. By utilizing these metamaterial-inspired shapes, small antenna dimensions ranging from $\lambda/8$ to $\lambda/12$ are achieved. Meanwhile, the design process is straightforward and the antennas have adequate radiation characteristics with sufficient bandwidth and high radiation efficiency that exceeds 50%.