Half-mode Substrate Integrated Waveguide Technique Research Articles

Half mode rectangular SIW slotted antenna for multiband operations using ANN optimization

AbstractA multiband half‐mode substrate integrated waveguide (HMSIW) slotted antenna is developed for ISM/WiMAX/WLAN applications. HMSIW technique has been utilized to acquire antenna compactness. Two inverted L‐shaped slots of half wavelength are embedded onto a HMSIW rectangular cavity for attaining a hybrid mode (i.e., Half‐mode of Half‐mode of ), which induces a lower resonance at 2.4 GHz. An inverted L‐shaped slot is influenced to radiate hybrid mode at 2.4 GHz, while the innermost inverted L‐shaped slot radiates modified mode at 3.30 GHz. A multiband is obtained by amalgamation of hybrid mode (at 2.4 GHz), modified mode (at 3.30 GHz) and modified mode (at 5.38 GHz). The radiating modes are elucidated by using mode theory methodology for ascertaining the resonance characteristics of the prototype antenna. The antenna parameters have been optimized by artificial neural network technique using MATLAB. The antenna geometry possesses a shrinkage size of 30 × 16 × 1.6 mm3, which has been designed on FR‐4 substrate. To vindicate the simulated consequence, the fabricated prototype has been tested. It contributes the fractional bandwidth of 6.4% (2.09−2.23 GHz) in the hybrid mode at 2.18 GHz, 9.03% (2.89−3.17 GHz) in the half cavity mode at 3.10 GHz and 9.96% (5.11−5.65 GHz) in the half cavity mode at 5.42 GHz, respectively, which is beneficial for ISM, WiMAX and WLAN band wireless applications.

Ultra-Compact Dual-Band Half-Mode substrate integrated waveguide filter and filtering power divider based on metamaterial concept

In this paper, a novel dual-band (DB) half-mode substrate integrated waveguide (HMSIW) filter and three novel equal/unequal DB HMSIW filtering power dividers (FPDs) based on the metamaterial concept with ultra-compact dimensions are proposed. The working principle of the proposed configurations is based on the theory of evanescent-mode propagation. Based on the metamaterial concept, a novel compact metamaterial unit cell with double negative permittivities by combining two different types of metamaterial unit cells has been introduced. By loading the proposed metamaterial unit cell with dual negative effective permittivities at different frequencies on the HMSIW surface, two forward passbands have been generated, independently. These two passbands are located below the waveguide cut-off frequency of the dominant mode in the HMSIW structure, which have been designed for WiMAX and WLAN applications. The resonance frequencies of each metamaterial unit cells can be arbitrarily regulated. Accordingly, by resizing the dimensions of each unit cells, the center frequencies of the introduced unit cell could be separately controlled. Four different techniques have been utilized to reduce the size of the proposed devices, which are the evanescent mode technique, HMSIW technique, meander technique, and fractal technique. To illustrate the performance of the proposed structures, the designed dual-band filters (DBFs), and equal DB FPD have been fabricated and measured. A reasonable agreement between simulated and measured results has been achieved. The total size of the proposed HMSIW DBF and FPD is about 0.10 λg × 0.10 λg. The proposed devices have many advantages in terms of compact size, low insertion loss, high selectivity, easy integration with the other planar circuits, and flexible bandwidth allocations.

Analyses of Combined DSRR and EBG Structures Over SIW and HMSIW for Obtaining Band Pass Response

Effect of combination of dual split ring resonator and electromagnetic bandgap structures over substrate integrated waveguide and half-mode substrate integrated waveguide (HMSIW) transmission line sections to obtain band pass property is presented in this paper. Greater control over the insertion loss (IL) within the transmission pass-band as well as the stop band isolation of the BPF is obtained by detailed study on several parameters of the proposed structure. The proposed design is further miniaturized using HMSIW technique keeping other useful parameters unaltered. The BPF structure is designed considering Neltec NH9320 material of thickness 30 mils and dielectric constant of 3.2. The filter achieves very small IL and wider bandwidth covering major part of microwave Ku frequency bands (12–18 GHz) with good stopband isolation. The designs are fabricated and measured results come with close approximation with the simulated outcomes.

Design and experimental verification of dual‐Fed, self‐diplexed cavity‐backed slot antenna using HMSIW technique

A dual-fed low-profile self-diplexed slot antenna is proposed for 5.2/5.8 GHz applications. The antenna mainly comprises a half-mode substrate integrated waveguide (HMSIW)-based cavity, loaded with a slot and microstrip feedlines. A radiating slot is etched on the upper metal cladding of the HMSIW cavity which splits the cavity into two sections. When each section is excited by using two orthogonally placed feedlines, it generates two frequency bands around 5.2 and 5.8 GHz. By finely tuning the antenna dimensions, a very high isolation of better than 30 dB is realised between the input-ports. Thereby, the proposed antenna exhibits the self-diplexing property. Finally, the proposed antenna is fabricated and the experimentally tested. The experimental results show a close mutual agreement with simulations. Moreover, the antenna shows unidirectional, stable and similar radiation characteristics at both the operating frequencies with maintaining planar configuration. The proposed design provides an easier, compact and a more cost-effective solution for RF front-end components and substitutes the conventional complex diplexer networks.

A Half-Mode SIW Cavity-Backed Semi-Hexagonal Slot Antenna for WBAN Application

ABSTRACTA half-mode substrate integrated waveguide (HMSIW) antenna covering industrial, scientific, and medical radio band at 5.8 GHz is designed, fabricated, and tested. An HMSIW technique is used to reduce the size to almost 50% while maintaining the same performance of the antenna. Afterwards, a semi-hexagonal slot is etched on the patch, which excites and tunes the dominant-mode of the cavity in the band of interest. Inspite of a substantial miniaturization, the proposed antenna provides a gain of 6.1 with front to back ratio of more than 10 dB along with a fair radiation efficiency of 83% in free space. In order to examine the performance of the antenna in the presence of a body, the antenna is tested on pork tissues. The measured on-body peak gain and simulated radiation efficiency are obtained as 5.25 and 69%, respectively. The antenna shows robust performance in the presence of pork tissues and the specific absorption rate value is under the Federal Communications Commission (FCC) guidelines, which makes it a suitable choice for wireless body area network applications.

Half Mode Substrate Integrated Waveguide Cavity based RFID Chipless Tag

This study presents the design of a compact Radio Frequency Identification chipless tag, with reduced size, important quality factor and improved results. The proposed prototype is based on Substrate Integrated Waveguide technology using the Half-Mode Substrate Integrated Waveguide technique to reduce the tag size by the half and preserve the same response. Further, the operating frequency band is from 5.5 to 8 GHz inside a compact surface of 1.3 × 5.7 cm². The frequency domain approach is adopted based on the frequency shift coding technique.

Development of a Low-Profile Circularly Polarized Cavity-Backed Antenna Using HMSIW Technique

In this paper, two single fed low-profile cavity-backed planar slot antennas for circular polarization (CP) applications are first introduced by half mode substrate integrated waveguide (HMSIW) technique. One of the structures presents right handed CP (RHCP), while the other one offers left handed CP (LHCP). A single layer of low cost printed circuit board (PCB) is employed for both antennas providing low-cost, lightweight, and also easy integration with planar circuits. An inset microstrip line is used to excite two orthogonal quarter-wave length patch modes with required phase difference for generating CP wave. The new proposed antennas are successfully designed and fabricated. Measured results are in good agreement with those obtained by numerical investigation using HFSS. Results exhibit that both antennas present the advantages of conventional cavity backed antennas including high gain and high front to back ratio (FTBR).

Development of a Linearly Polarized Cavity-Backed Antenna Using HMSIW Technique

In this letter, a novel scheme for linear polarized cavity-backed antennas is introduced. In this design, for the first time, half-mode substrate integrated waveguide (HMSIW) technique is used to create a radiating aperture rather than minimizing the structure. The proposed antenna has the advantages of compactness, low profile, light weight, low fabrication cost, and easy integration with planar circuits. It also can be easily implemented by using only a single layer of printed circuit board (PCB). The proposed antenna is numerically investigated using HFSS. A sample antenna is fabricated, and its radiation characteristics are measured. The radiation patterns of the proposed antenna are also calculated based on the aperture antennas theory. Good agreement among calculated, simulation, and measured results is observed. The measured results show that the proposed antenna has also the advantages of conventional cavity-backed antennas including high gain, low cross-polarization level (CPL), and high front-to-back ratio (FTBR).