Simulation and Comparison of Two Small Ultra Low-Profile Ultra Broadband Blade Shape antenna

Two ultra-wideband small blade shape antenna are presented and compared. First structure is composed with a blade radiator with a lossy element on the feed point. The second structure has composed with a monopole with a meanderline load. This antenna has three lumped RLC elements that optimized for higher gain and return loss. The antenna is shaped like a very thin blade monopole and is constructed with an one-sided printed board. The dimension of both antennas is 22 × 76 cm (0.076 λ × 0.022 λ × 0.00015 λ of lowest frequency) with a 25 × 50 cm ground plane. It is showed that the characteristics of second antenna are too better than first one, especially in lower frequencies. The advantage of second antenna is the higher gain and removing the gain notches in line of sight despite of small size and a good matching in 30 – 500 MHz frequency band.