Mouse anti-DBI monoclonal antibody

This letter presents a microstrip patch antenna array fed with a low-loss and highly efficient feeding structure called empty substrate-integrated waveguide (ESIW). The proposed antenna array targets 5G wireless communication systems operating at 28 GHz. The antenna array consists of 4 x 4 radiating patches, where every four radiating elements are grouped together forming a 2 x 2 subarray and each of the subarrays is fed by ESIW feeding network by aperture coupling. The experimental results demonstrate good agreement with the simulated results, offering a wide |S-11| < -10 dB bandwidth of 12.4%, i.e., 26.5-30 GHz. A peak gain of 18.2 dBi and a high efficiency of about 91% are achieved using the proposed structure. Furthermore, the low-profile substrate of the ESIW feeding structure makes seamless integration of the proposed antenna array with the millimeter-wave front end. The advantages, such as low fabrication cost and high efficiency, make the proposed antenna array a suitable solution for millimeter-wave 5G wireless communication systems.

We propose a wideband, low-loss, low-cost, and high-gain metallic phased array for tactical air navigation (TACAN) systems. Such an array composed of 12 slot patch antennas with an air substrate. The element of this array has been optimized for working in 950 similar to 1250 MHz with a gain of 9 dBi. For using such an array in the TACAN system, an iterative method is utilized for synthesizing a cosecant-squared pattern (CSP). This method optimizes the element excitation in a linear phased array and allows having fewer ripples in the shaped region and lower sidelobe level (SLL). The obtained excitations by means of this method are realized using an all-metal feed network. Such a feed structure does not use any phase shifter and its dimensions are optimized on the air substrate to operate in the wideband frequency range and to be a low-loss and low-cost structure. To validate the numerical and analytical results, the entire system, i.e., the antenna array along with its feed network, is fabricated and successfully measured. The measurements on a 180 cm x 24 cm array and 550 mm x 350 mm feed network show a CSP with a maximum gain of 12.4 dBi and SLL <-23 dB at the central frequency of TACAN bandwidth (962 similar to 1213 MHz).