Microstrip Phased Array Antenna Research Articles

Design of a 2*2 Microstrip Phased Array Antenna for Radar Applications

Micro-strips patch antennae used in array configurations are more beneficial than single antenna element by augmenting the directivity (dB) radiation pattern, and lowering the substrate's permittivity to overcome its drawbacks, which include poor gain, low efficiency, narrow bandwidth limited directivity. It also facilitates beam-steering capability which is obtained by enabling phase difference(β) between the antennas. Beam scanning capability is used in radar and GNSS technologies. This paper proposes a 2*2 microstrip phased array antenna by using rectangular microstrip patch antenna on an FR-4 dielectric substrate for beam scanning. The resonant frequency of the antenna is at 2.52GHz frequency with a good Voltage Standing Wave Ratio (VSWR) value of 1.1325. The design has been simulated in Ansys HFSS software. The simulation results exhibit antenna better performance of the proposed antenna compared to state-of-art designs present in the literature. The compactly designed Rectangular Micro-strip Patch Antenna array shows a low S-parameter (–24.127858 dB), high gain (13.689104 dB), directivity (14.055125 dB), and efficiency of 91.917%.

MmWave multibeam phased array antenna for 5G applications

A fully integrated 28 GHz, 5G mmWave microstrip phased array antenna on a multilayer substrate is presented. The proposed array provides independently steerable, simultaneous multiple beams in any arbitrary azimuth, elevation angles with equal or unequal peak gains. A computation method is proposed to calculate the weights required to generate multiple beams. Multiple beams (up to six) over various arbitrary angles are generated using the proposed method and the results are presented. The inherent amplitude and phase variations due to the hardware impairments are independently captured through simulation and measurements, and their impact on the performance of the phased array is analyzed. Measured results are compared with simulations for single, dual, and multiple beams over arbitrary angles. The phased array performance is measured and presented over and scan angles in azimuth and elevation planes respectively over 400 MHz bandwidth for both single and dual beam deployment. The proposed multibeam computation method is validated with measurements at 28 GHz for a dual beam case, (, ) and (, ) in azimuth plane for equal and unequal power beams with a side lobe level of better than 17 dB.

Design of Linearly and Circularly Polarized Microstrip Phased Array Antennas

Design of Linearly and Circularly Polarized Microstrip Phased Array Antennas

Exploiting Higher Order Modes for Grating Lobe Reduction in Scanning Phased Array Antennas

A new approach is proposed to reduce the grating lobes by exciting higher order modes of conical radiation patterns in microstrip phased array antennas with a one-wavelength element spacing for medium- and wide-scan angles. The proposed concept utilizes the scanning and nulling capabilities of combined higher order modes of a circular microstrip patch as an antenna element in a seven-element hexagonal array. These elements facilitate providing suitable radiation-matched patterns for wide-scanned angles and simultaneously reducing the grating lobes for large element spacing in the order of one wavelength. In particular, for the scan angles of 35°–75°, two higher order modes, namely the TM21 and TM31, are excited and the grating lobes are reduced to well below −30 dB. The proposed method is also shown to be effective for near the horizon scanning with a $0.8\lambda _{\mathrm {o}}$ element spacing.

Performance enhancement of a compact wideband patch antenna array using EBG structures

In this paper, a compact wideband linear microstrip phased array antenna (MPAA) is proposed. To reduce the size of MPAA, a compact wideband aperture coupled microstrip patch antenna (MPA) is utilized as array element. Size reduction of the array element is performed through incorporating an interdigital capacitor (IDC) in the patch and a metamaterial (MTM) unit cell close to slot in the ground plane of the antenna. By cutting two vertical slits from the slot, further compacting of the slot in the ground plane of array element is obtained. By this technique dimensions of the patch and slot are reduced by 12.9% and 12.2%, respectively. Furthermore, dimensions of the MPAA are reduced through decreasing the spacing between array elements causing the antenna performance degradation. To overcome this shortage and improve the radiation characteristics of the proposed MPAA, an electromagnetic bandgap structure (EBG) is utilized. The effect of implementing EBG cells on the reflection coefficient of the elements in the MPAA during beam scanning is studied in details. The maximum measured gain, bandwidth and cross-polarization level of the fabricated MPAA are 13.3 dBi, 24.4% and −40 dB, respectively making it a good candidate for monopulse tracking radar applications. The measurement results confirm the simulation results.

Cantilever RF-MEMS for monolithic integration with phased array antennas on a PCB

This article presents the development and operation of a novel electrostatic metal-to-metal contact cantilever radio-frequency microelectromechanical system (RF-MEMS) switch for monolithic integration with microstrip phased array antennas (PAAs) on a printed circuit board. The switch is fabricated using simple photolithography techniques on a Rogers 4003c substrate, with a footprint of 200 µm × 100 µm, based on a 1 µm-thick copper cantilever. An alternative wet-etching technique for effectively releasing the cantilever is described. Electrostatic and electromagnetic measurements show that the RF-MEMS presents an actuation voltage of 90 V for metal-to-metal contact, an isolation of −8.7 dB, insertion loss of −2.5 dB and a return loss of −15 dB on a 50 Ω microstrip line at 12.5 GHz. For proof-of-concept, a beam-steering 2 × 2 microstrip PAA, based on two 1-bit phase shifters suitable for the monolithic integration of the RF-MEMS, has been designed and measured at 12.5 GHz. Measurements show that the beam-steering system presents effective radiation characteristics with scanning capabilities from broadside towards 29° in the H-plane.

Digital broadband multibeam phased-array antennas

The methods for constructing digital microstrip phased-array antennas (PAAs) providing formation of several independent beams in space and having a relative bandwidth not less than 20% are analyzed. The effect of the PAA-element parameters on the bandwidth is determined, the methods for reducing the level of lateral lobes are compared, and the formation of multiple independent beams in a PAA is analyzed.

Vehicular Radio Scanner Using Phased Array Antenna for Dedicated Short Range Communication Service

Now a day’s accidents are very common due to increased population of vehicle. In order to ensure safety measures in the vehicle this paper has proposed some methodologies regarding careful driving by automatically scanning and analyzing the blind spot area of an intelligent mobile vehicle. A vehicular antenna with minimum perturbation is proposed to be fitted on the vehicle and collect information of the concern area which would ensure visibility of the operator i.e. masked or integrated within the car body. This paper has dealt with the design of Tchebyscheff polynomial based prototype planar microstrip phased array antenna and also redesigned the same when implemented in the body of the car being considered as an electromagnetically large element. Both the design has been experimentally verified with the measurement. The simulated and the measured results in both the cases are found to be in good agreement. More than 11 dB gain was observed at perfectly 30° angles from its broad side direction as desired for blind spot detection with minimum amount of electromagnetic interference inside the car.

Ni ferrite based microstrip phased array antenna in L-band

Ni ferrite based microstrip phased array antenna in L-band

Ni Ferrite Based Microstrip Phased Array Antenna in L-band

Characteristics of Ni ferrite based microstrip phased array antenna in terms of the switchability, radiation patterns and gain have been investigated using transmission line model. The radiation characteristics of antenna are described with a normal magnetic bias field towards the plane of ferrite substrate considering the phase excitation difference between the patch elements π/2 and π/4. It is observed that by properly varying the relative phases, it is possible to steer the direction of radiation. This advantage is applicable in radar, search/track applications.

RFID Coverage Extension Using Microstrip-Patch Antenna Array [Wireless Corner

In this paper, a UHF-band 2 times 2 microstrip phased-array antenna is designed and implemented to extend the coverage of an RFID reader system. The phased-array antenna has four microstrip-patch antennas, three Wilkinson power dividers, and a transmission-line phase shifter. These are printed on a dielectric substrate with a dielectric constant of 4.5. The array has dimensions of 34 cm times 45 cm, operating at a frequency of 867 MHz, as specified in RFID Gen2 protocol European standards. The phased-array antenna has a measured directivity of 12.1 dB, and the main-beam direction can be steered to angles of plusmn 40deg, with a HPBW of 90deg. The phased-array antenna is used as the receiving antenna in a commercial reader system. Experimental results indicate that the coverage of the RFID system with the phased-array antenna is superior to the coverage with a conventional broader-beamwidth microstrip-patch antenna. The proposed system can also be used for a wireless positioning system.

Predicted performance of magnetized semiconductor phase shifters for millimeter-wave microstrip array antennas

The tunable phase shift of a planar magnetized semiconductor phase shifter is presented, suitable for an integrated environment due to its miniature size, low-biasing requirements, and lower material related problems at millimeter-wave frequencies. A linear microstrip phased array antenna with an integrated semiconductor phase shifter is designed and the calculated beam steering properties are tabulated. The design process is verified by simulating similar ferrite-based linear phased array antennas.

Radiation characteristics of cylindrical microstrip phased array antenna mounted on electrically large cylinder

A problem of a microstrip cylindrical phased array antenna mounted on an electrically large cylinder is discussed. The array antenna consists of N patches, which are placed in the azimuthal plane. The solution is obtained by the method of moments (MoM) in the spatial domain using an improved representation of the spatial Green's function. In this representation, a leaky-wave contribution is extracted in addition to the previously extracted singularity at the origin and a surface-wave contribution. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 44: 152–157, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20573

A modular approach for probe-fed and capacitively coupled multilayered patch arrays

We present a modular technique for analyzing probe-fed, multilayered microstrip phased-array antennas. Each patch layer is assumed to be infinite in extent and represented by its generalized scattering matrix (GSM) with respect to a finite number of Floquet modes. For multilayer patch analysis, the individual GSMs are combined appropriately to yield the overall GSM of the structure. The individual GSM are obtained using the Galerkin method. The probe layer is represented by its generalized impedance matrix (GIM) which is deduced using Floquet modal analysis and the variational method. The GSMs and GIM are combined appropriately to yield the input impedance seen by the probe. Numerical results computed with this technique are shown to agree favorably with available data. Results for two-layered patch arrays and capacitively coupled patches are also presented.

Infinite phased arrays of microstrip antennas with parasitic elements: application to bandwidth enhancement

Microstrip phased array antennas obtained by the association of two interdigitated biperiodic coplanar subarrays are presented. One of these two subarrays is fed, and the other is parasitic. This type of array is studied for rectangular or triangular patches, using an infinite phased array model for the theoretical approach. The frequency bandwidth obtained with this geometry is larger than that of conventional monolayer microstrip antennas. >