This article presents a phased array antenna employing MEMS phase shifter. The proposed phased array antenna consists of eight square patch antennas operating at 10. 4 GHz with a bandwidth of 400 MHz. Feed line for each patch passes through a MEMS phase shifter realized by a series of bridges above the transmission line. The distance between the bridge and the transmission line underneath it is adjusted using a control signal applied to them, which in turn, introduces a loading effect on the feed signal. This changes the effective length of the feed line and provides phase shifts with 15-degree resolution. Low loss conversion units are employed in order to couple the phase shifter and microstrip lines. The integrated numerical analysis approach applied to phased array antenna employing MEMS phase shifter and the scattering parameters and radiation patterns at different steering angles demonstrate the effectiveness of employing MEMS phase shifters in designing phased array antennas. The proposed design methodology might be applied to other frequency bands, such as millimeter-wave for automotive applications. Employment of MEMS phase shifters instead of solid-state ones provides high linearity, high power handling, and wide frequency range of operation.

In this paper, a metamaterial based toroidal ferrite phase shifter design algorithm has been introduced in X band. For the design of such a phase shifter, first the MNG (negative μ ) ferrite core in extraordinary bias mode should be implemented. Then, the ENG (negative ε ) part composed of parallel metallized lines should be designed on a substrate board. Finally, the input and output port impedance matching could be accomplished by using two section dielectric step transformers layout using binomial tapering method. According to the simulation results, the closed toroidal ferrite core shape, has treated the main disadvantage of metamaterial waveguide phase shifter’ s experimental bias complications, and it has reduced the amplitude of magnetic bias filed from the typical range of (6-7 kOe) to under the acceptable 100 Oe value, which could be achieved using a simple wire. Moreover, by introducing a new core structure and an impedance matching network in the proposed phase shifter, the second main disadvantage of the metamaterial-based ferrite phase shifter which is their high insertion loss, has decreased from 10 dB to 3. 2 dB.

In this paper, a new X band Metamaterial (MTM) based ferrite phase shifter is presented. The phase shifter is excited by circular polarized wave base on combination of TE10 and TE01 modes in a square waveguide. In order to synthesize negative index material (NIM), negative permeability of ferrite slabs in extraordinary mode is mixed with the negative permitivity of printed periodic metallic wires on substrate, in the same frequency band. By using the introduced new circular polarized MTM based layout, the proposed phase shifter loss is less than 3 dB, while the loss of MTM waveguide phase shifters is about 10 dB. Also, the proposed phase shifter profits the miniaturization property of MTM design usage. The total length of the phase shifter is 2 cm with 360° differential phase shift, compared to common dual mode phase shifter with 6 cm length in X band.

In this paper, new topology of phase shifter is proposed that uses advantage of metamaterial and MEMS technology. The phase shifter is switched between two states of RH-and LH-TL having frequency passband unlike other proposed metamaterials which create the maximum phase shift from one unitcell. Analysis and design approach of the phase shifter is presented and the structure is simulated using 3D simulator. The phase shifter creates 180 degree phase shift with return loss and insertion loss that are better than 15 dB and 0. 25 dB in both states at frequency ranges of 1. 4-4. 4 GHz. Therefore, low loss, high bandwidth and high phase shift are the advantages of the new proposed phase shifter.

The advancement of technology has significantly increased the importance of defense systems that can scan and identify attacking targets. These systems rely on phased array antennas to achieve their functionality. The beam remains fixed in a perpendicular orientation without such antennas, preventing effective target detection. Historically, beam rotation was accomplished either mechanically or electronically. Mechanical methods involved the use of levers that required constant rotation, whereas electronic beam rotation was enabled solely by phased array antennas. This process necessitates the use of phase shifters, which are typically implemented using either pin diodes or ferrites. In this article, pin diodes are utilized due to their advantages, including high switching speed, reversibility, and superior availability compared to ferrites.rowParametersAmount1Total angle covered45Degree2half power beam width°183Angle change stepLess than 5°4Polarizationlinear5Return Loss (VSWR)Less than 1.56Total weight (antenna, control board, and feeding network)1 kilogram7Dimensions15 cm × 15 cm × 10 mm8Tolerable power1 watt9A(area)126mm10Horn a 35mm11Horn b27mm12horn flare length2inch13C 14Center frequency9.5 G15λ=c/f3× /9.5=31.5 Rather than placing all the PIN diodes on a single unit and rotating the entire antenna pattern to the desired angle, this approach proves to be inefficient, as replacing the PIN diodes each time would be impractical. Additionally, constructing such a system would be highly complex. To address these challenges, a more efficient solution involves quantizing the PIN diode phases into two discrete states: 0° (off) and 180° (on), which are incorporated into a single-bit unit cell with dimensions of 7 × 7. This configuration allows for the beam to be rotated to the desired angle while maintaining system simplicity. However, one important characteristic of this type of antenna is that, as the scanning coverage angle increases, the antenna gain decreases.