A compact feeding network with radiation contribution for X‐band marine radar antenna array applications

Abstract

A compact feeding network with radiation contribution is proposed in designing microstrip patch array antenna (MPAA) for X-band marine radar applications. The 1-to-4 feeding network consists of two circular-sector patch balun, which can radiate electromagnetic wave with the same polarization of the patch array for enhancing the gain and suppressing the cross polarization. The feeding line in the series-fed patch subarray is modified as the step-impedance microstrip line to decrease the side-lobe level (SLL). To verify the method, a 28-element 9.41-GHz MPAA with the proposed radiated feeding network is designed and fabricated. Measured results show that the impedance bandwidth is 183 MHz with a peak gain of 21.3 dBi. The SLL is 27.8 and 21.4 dB in the E-and H-planes, respectively. The cross polarization is effectively reduced, which is lower than the copolarization of about 57 dB. K E Y W O R D S cross-polarization suppression, gain enhancement, patch array antenna,

Low‐sidelobe marine radar microstrip array antenna based on hybrid algorithm and metamaterial

“…The high gain in 2,18,19 and 21 are due to the large number of elements, which leads to a larger profile. In the horizontal plane at the center frequency, the HPBW of this design is closer to, 1,21 and is narrower than, 816–19 and, 22 which indicates that the design in this paper can accurately judge the direction. Compared with, 16,17 the proposed antenna has a narrower HPBW in the vertical plane, which can reduce the sea clutter.…”

“…In the horizontal plane at the center frequency, the HPBW of this design is closer to, 1,21 and is narrower than, 816–19 and, 22 which indicates that the design in this paper can accurately judge the direction. Compared with, 16,17 the proposed antenna has a narrower HPBW in the vertical plane, which can reduce the sea clutter. As for the CPL, the proposed antenna is lower than the antenna in, 1,2,8,1719,21 and 22 .…”

“…As for the CPL, the proposed antenna is lower than the antenna in, 1,2,8,1719,21 and 22 . Compared to horizontal polarization in 1,7,8,16 and, 21 this design has better performance on rainy days because the raindrops are oblate in the air. The above comparison shows that the proposed antenna has excellent overall performance and the lowest SLL.…”

“…The proposed antenna shows the lowest SLL compared with other designs at center frequency in both the horizontal and vertical plane. In the item of peak gain, the proposed antenna is larger than the antenna in, 7,8,16,17,22 and is similar to 1,20 . The high gain in 2,18,19 and 21 are due to the large number of elements, which leads to a larger profile.…”