Design of Small CRPA Arrays with Circular Microstrip Loops for Electromagnetically Coupled Feed

Abstract

This paper proposes a design of small controlled reception pattern antenna (CRPA) arrays using circular microstrip loops with frequencyinsensitive characteristics. The proposed array consists of seven identical upper and lower circular loops that are electromagnetically coupled, which results in a frequency-insensitive behavior. To demonstrate the feasibility of the proposed feeding mechanism, the proposed array is fabricated, and its antenna characteristics are measured in a full-anechoic chamber. The operating principle of the proposed feeding mechanism is then interpreted using an equivalent circuit model, and the effectiveness of the circular loop shape is demonstrated by calculating near electromagnetic fields in proximity to the radiator. The results confirm that the proposed feeding mechanism is suitable to have frequency-insensitive behavior and induces strong electric and magnetic field strengths for higher radiation gain in extremely small antenna arrays.

Bandwidth-Enhanced Circularly Polarized Crescent-Shaped Slot Antenna via Circular-Patch Loading

“…To validate the simulation results, a prototype of the proposed antenna with the optimized parameters, as tabulated in Table 1, was fabricated for measurement. Figure 6 displays the fabricated antenna, which has overall dimensions of 50.8 × 50.8 × 0.5 mm 3 . The reflection coefficient was tested using an Agilent 8510C RF network analyzer.…”

“…With rapid progress in the field of modern wireless communications, there is increasing demand for compact and broadband antennas [1][2][3]. The printed-slot antenna is a promising candidate due to its obvious advantages, such as wide impedance bandwidth, low cost, low profile, and ease of fabrication.…”

Near-Field Immunity Test Method for Fast Radiated Immunity Test Debugging of Automotive Electronics

“…The conventional loop [23][24][25][26][27] or helical/helix shaped [28][29][30] antennas used as magnetic field antennas cannot produce the required high magnetic field intensity with the constraint of the low input feed power for the near-field magnetic field testing as per the NFIT setup of Figure 2. The embedding of high permeability materials such as ferrites in the antenna structure (sandwiching between the antenna radiator and ground plane as in [31,32]) could enhance the intensity of the generated magnetic field by the antenna.…”

High-Gain Waveguide-Fed Circularly Polarized Spidron Fractal Aperture Antenna

“…However, the waveguide-fed fractal aperture antennas reported in earlier work [4] are mostly linearly polarized antennas. In most practical satellite communications and radar systems, circularly polarized (CP) antennas are preferred for their ability to alleviate multipath and fading effects and to provide a more flexible orientation between RF (Radio Frequency) transmitting and receiving antennas [5][6][7][8][9]. Therefore, it is of interest to design waveguide-fed fractal aperture antennas with circular polarization.…”