Low-cost Microstrip Research Articles

Low-cost microstrip sensor based on coupled step line (CSL) resonator for blood plasma glucose determination

In this paper, a microstrip sensor structure was designed and implemented to detect blood glucose levels (BGL) based on changes in resonant frequencies, achieved by creating couplings at sensitive regions. A coupled step line was used to create a sensitive region on the sensor suitable for BGL testing. Transmission matrix theory was employed for the mathematical analysis to obtain the resonant frequency. Received blood samples from 50 different patients were centrifuged, and their serums were extracted to study the performance of the microchip sensor. By placing individual serum samples (50 µl) at the sensitive region of the sensor, the scattering parameters of the sensor were measured to investigate the resonant frequency variation. In addition, the effects of basic blood parameters were analyzed based on the amount of frequency shift. High sensitivity, suitable quality (Q) factor, compact size, and acceptable reproducibility of the measured results are important features of the developed sensor.

A Low-Cost Patch-Antenna for Non-Invasive Brain Cell Detection

Cancer is one of the most and frequent causes of death around the world. Brain tumor is a critical and dangerous type and has a few difficulties of the techniques used for its detection; it is hard to determine its location when it is small at an early stage. The purpose of this work is to design a patch antenna sensor that is a low-cost microstrip which is suitable to detect a brain cancer tumor. The computer simulation technology CST Studio Suite 3D EM simulation and analysis was used to design a patch antenna with different frequencies of 2.8 GHz, 3.9 GHz, 5GHz and 5.6GHz to diagnose brain tumors. A comparison study between these resonance frequencies (lower-band (L-B) 2 GHz, middle-band (M-B) 3.9-5 GHz and upper-band (U-B) > 5 GHz) has been performed with six layers of brain phantom of fat, dura, brain, skin, CSF (Cerebrospinal Fluid) and skull. The designed patch sensor was assessed on both scenarios without and with a tumor cell on a brain phantom. Three parameters have been observed, the frequency phase shift, the deep amount of reflection return loss and power absorption were used to indicate the presence of the tumor cell. This study concludes that the middle-band (M-B) results in good penetration and better return loss depth around - 20dB. Meanwhile, the higher band provides high resolution of 21 MHz phase-shift but with only depth value of difference return loss of -0.1dB. The proposed work could provide a pathway on the design of patch sensors for biomedical applications.

Performance enhancement of low-cost microstrip patch antennas through 3D-printed conductive geometric forms

With the development of new wireless communication systems, antennas will require excellent characteristics, including high gain, wide bandwidth, and low losses. 3D printing creates structures through an additive process, layer by layer, which enables the manufacturing of antennas with 3D shapes in a cheaper, faster, and more flexible manner. This paper presents a new design for a 3D-printed microstrip patch antenna in the Wi-Fi band with the objective of improving the performance of planar 3D-printed patch antennas. The antenna is fabricated using PLA (Polylactic Acid) as the substrate, Electrifi conductive filament and cooper tape ground. In order to improve the radiation characteristics and overall efficiency of the antenna, two different three-dimensional forms (pyramid and frame) are employed to optimize key parameters, contributing to improved radiation characteristics and overall efficiency. A comparative analysis is presented, highlighting the advantages of the proposed design over traditional two-dimensional counterparts. The experimental results demonstrate enhanced bandwidth and gain, showcasing the potential of the 3D microstrip patch antenna for advanced wireless communication applications.

A Low-Cost Microstrip Patch Antenna Based Metamaterials for Non-Invasive Breast Tumor Detection

Microstrip patch antennas have been used extensively in broadband telecommunication applications. Despite their countless promises, their narrow bandwidth and the loss at high-frequency bands have limited their usage in medical applications. The purpose of this work is to design a patch antenna sensor that is a low-cost microstrip sensor which is suitable for biomedical application to detect a breast cancer tumor. The proposed antenna sensor is comprised of three layers namely ground, substrate and microstrip patch sensor that can be easily fabricated by using standard printed circuit board technique. The comparison study between two resonance frequency at 1.8 GHz and 2.9 GHz has been performed and investigated by especially accurate simulation with the presence and absence of tumor cell. Results obtained using computer simulation technology CST Studio Suite 3D EM simulation and analysis software indicates that the design can detect tumor by using phase shift detection and depth of the return loss. The result shows that the antenna return loss is getting lower in -39 dB at 1.8 GHz and -12 dB at 2.9 GHz and the phase shift detected with the presence of the tumor cell. Specific absorption rate has been also calculated (0.746 and 0.934 W/kg) and found to be in acceptable range and not exceed the standard value of <1.6 W/kg, which mean that the patch sensor is compatible for human and biomedical application. The breast phantom models without/with a tumor have been numerically simulated by using the antenna operating as a transceiver for the detection of cancer tumor cells. Two parameters have been observed, the frequency phase shift and the deep amount of reflection return loss. In summary, this study concludes that a lower frequency band will result in higher penetration depth but a lower resolution. Meanwhile, higher frequency band will provide a better resolution, but the penetration depth will be lesser as seen in the comparison study between 1.8 GHz and 2.9 GHz. The proposed work could provide a pathway on the design of electromagnetic sensors for biomedical applications.

A Low-Cost and Dual band Microstrip Patch Antenna for Ku and K Band Applications

This paper examines a dual-band, low-cost microstrip patch antenna for Ku and K applications through simulation study. Ansys High Frequency Structure Simulator (HFSS) software is used to do the simulation analysis of the suggested antenna. Using Ansys High Frequency Structure Simulator (HFSS) software, the suggested antenna is constructed and simulated to evaluate several characteristics including reflection coefficient (S11), radiation pattern, gain, and bandwidth. The substrate for the antenna is made of FR-4, which has a relative permittivity of 4.4 and a dielectric loss tangent of 0.02. Using the microstrip feed line technology, the planned millimeter wave dual band antenna is examined at operating frequencies of 13 and 22 GHz. At frequencies of 13 and 22, respectively, the antenna's maximum gain values are 4.81 dB and 4.82 dB in the x-y plane. The suggested material might be a decent substitute.

Low-Cost Antenna-Array-Based Metamaterials for Non-Invasive Early-Stage Breast Tumor Detection in the Human Body.

Microstrip patch antennas have been used in many applications since their appearance. Despite their great promise, their narrow bandwidth and the loss at high-frequency bands have limited their usage in medical applications. This work proposes a developed low-cost microstrip patch antenna suitable for microwave imaging (MWI) applications within the wideband frequency range. The proposed antenna is loaded with an artificial magnetic conductor (AMC) to improve the antenna performance. The simulated results obtained using computer simulation technology (CST) indicate that the presence of the AMC has improved the frequency selectivity of the antenna at 8.6 GHz with a peak realized gain of 9.90443 dBi and 10.61 dBi for simulated and measured results, respectively. The proposed microstrip antenna has been fabricated to validate the simulated results, and its performance is tested experimentally. Additionally, the fidelity factor of face-to-face (FtF) and side-by-side (SbS) scenarios have been presented. The breast phantom models with a tumor and the antenna operating as a transceiver have been numerically simulated for the application of cancer tumor cell detection. The work will have a significant impact on the design of electromagnetic biosensors.

Improvement in Depth of Reflection Co-efficient below -20 dB for Millimeter–Wave Antenna

A low cost microstrip antenna is designed for mm–wave applications on FR4 substrate. It consist of patch, etched with an open polygon slot (OPS) at lower central edge of it and partial ground plane. This etching of OPS is used to improve depth of reflection co-efficient below -20 dB which is equivalent to mismatch loss (ML dB ) ≤ 0.04 dB. This proposed mm–wave antenna also provides 3 dBi– & 5 dBi–gain-bandwidth of 6 GHz (34.72—40.72GHz) & 3.91 GHz (34.72—38.63GHz) respectively with a peak gain of 12.4 dBi at 35.1 GHz and acceptable radiation efficiency of 58.05 %. Simple design, low manufacturing cost and ease of fabrication makes proposed antenna suitable for high end practical mm–wave applications.

A Dual-Band and Low-Cost Microstrip Patch Antenna for 5G Mobile Communications

This paper investigates the numerical and experimental analysis of a low-cost and dual-band microstrip patch antenna for the fifth generation (5G) mobile communications. The numerical analysis of the proposed antenna is performed using the computational electromagnetic simulator (CEMS) software which is based on the finite-difference time-domain (FDTD) and CST software which is based on the finite integration technique (FIT). The performance of the proposed antenna designed and fabricated on a low-cost FR-4 substrate is verified with the simulated and measured results. The antenna operates at dual frequency bands which are 24 and 28 GHz. The antenna maximum gain values are 3.20 dBi and 3.99 dBi in the x-y plane at 24 and 28 GHz, respectively. The proposed antenna provides almost omni-directional patterns suitable for 5G mobile communication devices.

A Low-Cost Microwave Filter with Improved Passband and Stopband Characteristics Using Stub Loaded Multiple Mode Resonator for 5G Mid-Band Applications

This paper presents the design and implementation of a printed circuit microwave band-pass filter for 5G mid-band applications, using a Stub Loaded Multiple Mode Resonator (SL-MMR) technique. The objective of this article is to introduce a low-cost microstrip filter with improved passband and stopband characteristics, based on a mathematical analysis of stub loaded resonators. The filter cost is reduced by selecting the low-cost FR4 dielectric material as a substrate for the proposed filter. Based on the transmission line model of the filter, mathematical expressions are derived to predict the odd-mode and the even-mode resonant frequencies of the SL-MMR. The mathematical model also highlights the capability of controlling the position of the SL-MMR resonant frequencies, so that the 5G sub-band that extends along the range (3.7–4.2 GHz) can perfectly be covered with almost a flat passband. At the resonance frequency, a fractional bandwidth of 12.8% (500 MHz impedance bandwidth) has been obtained with a return loss of more than 18 dB and an insertion loss of less than 2.5 dB over the targeted bandwidth. Furthermore, a pair of parasitic elements is attached to the proposed filter to create an additional transmission zero in the lower stopband of the filter to enhance the suppression of the filter stopband. The measured and simulation results are well agreed, and both reveal the acceptable performance of the stopband and passband characteristics of the filter.

A Low Cost, Low in-Band RCS Microstrip Phased-Array Antenna With Integrated 2-bit Phase Shifter

In this article, we present a low-cost microstrip phased-array antenna, which is composed of electronically reconfigurable elements. The p-i-n diodes' integrated elements have various functions, such as tunable polarization characteristics and adjustable radiation phases. The high sidelobe level (SLL) due to the 2-bit phase shifter can be reduced by a randomly rotated (RR) array element. It is shown that the array can realize electronic beam-steering capabilities and keep -10 to -14 dB sidelobes without tapering. To verify the above theory, an eight-element linear array prototype working at 3 GHz was designed, fabricated, and tested. Numerical simulations and experimental results show that, by controlling the “ON” and “OFF” states of p-i-n diodes, the radiation beam can be controlled to steer in a circular polarization (CP) mode, wherein the scanning angle is up to ±45°. Furthermore, the principle of suppressing the vector scattering field by the opposite phasing cancellation method can achieve in-band radar cross section (RCS) reduction. Simulation results show that approximately 15 dB in-band RCS reduction can be realized for both bistatic and monostatic RCS reduction with an 8×8 array.

Design of low-cost microstrip patch antennas with robust optimization

ABSTRACT This paper presents a robust optimization method to design patch antennas that consider uncertainties from the substrate electromagnetic properties and the manufacturing equipment. The robust optimization method is proposed to design an antenna that uses FR-4 as a substrate, addressing the uncertainties originated from the lack of standardization of this material properties and errors in the manufacturing process of the antenna. By addressing these uncertainties, robust design can result in a low-cost antenna with good performance that is less sensitive to deviations in the defined project variables. The optimization scheme used in this paper is based on NSGA-II, and the robustness of its solutions is quantified with the standard deviation of samples from the performance parameters in the uncertainty set from the design parameters. Two prototypes of patch antennas, one with linear and the other with circular polarization are designed, built, and measured.

Coir Composite Based Electronics for Microwave Charging of Electric Vehicles

Electric vehicles are becoming popular due to environmental concern and reduction in battery costs. Several charging methods are being investigated including microwave wireless charging. Design of low profile, planar transmission lines and antenna with high power handling capacity forms the backbone of microwave charging of electric vehicles. Unconventional substrates including coir provide good scope for designing planar structures with high power handling capacity. A novel low cost microstrip antenna and transmission line using Coir Phenol formaldehyde composite as a dielectric substrate is proposed. This is expected to be simple, easy-to-produce and inexpensive. The prototypes are designed, fabricated and measured for resonance frequency of 2.45GHz. The microwave parameters including ’S’ matrix and gain are simulated using electromagnetic simulator HFSS. Experimental results employing VNA E5080A showed good consonance with simulated results in the frequency range 900MHz to 4.0GHz. Encouraging terminal voltage is obtained at 2.45GHz making this substrate a potential candidate for vehicle charging applications.

A Novel Compact Isolation Circuit Suitable for Ultracompact and Wideband Marchand Baluns

A novel compact isolation circuit (IC) is proposed for the ultracompact and wideband UHF Marchand balun topology, and exact design formulas are presented for arbitrary coupling coefficients and impedance-transforming termination impedances. The wideband Marchand balun mainly consists of two identical coupled transmission-line sections which are far shorter than 90° long, connecting segment, two or three lumped elements and the proposed IC. The novel IC features −180° phase delay between two balanced ports, and makes the ultracompact implementation possible, which is quite different from the conventional ones with 180° phase delays between two balanced ports. In addition, due to the −180° phase delays, excellent isolation performance and excellent phase responses can be performed. For the proof-of-concept demonstrations, one prototype with each coupled-line section being only 20° long and the half IC being only 20° long is tested at 700 MHz. The measured frequency responses are in good agreement with the predicted ones with the performance of the 10-dB return loss bandwidth of 40% and −15 dB isolation bandwidth of 121.4%. In terms of sizes versus bandwidths, the fabricated Marchand balun can be regarded as the best and the smallest ever recorded, based on the low-cost microstrip technology.

Performance Analysis of Low-Cost Printed Antenna Array Elements for 5G LOS-MIMO Arrays at 60 GHz

Design of 5G and beyond 5G telecommunication systems relies on utilization of diverse solutions for different envisioned applications and different constituents of an entire system. One of the research directions is the utilization of a global unlicensed millimeter wave frequency band from 57 to 66 GHz for the high throughput data transfer. Apart from the wide spectrum availability at 60 GHz, there are many problems to be resolved before the concept can become fully functional; one of the requirements is the design of low-cost, energy efficient, wideband antennas with enhanced gain, capable of overcoming propagation losses at 60 GHz. We investigate the benefits and shortcomings of four types of low-cost, printed antennas as the constituents of sub-array elements for the large line-of-sight MIMO arrays. The results are put into perspective by comparison with the most used low-cost microstrip patch sub-array element. The state-of-the-art method-of-moments computations were employed in the highly accurate analyses of the four compared antenna array elements. Although the gains of such sub-arrays can be boosted by the increases in antenna numbers, this does not hold for the efficiency or bandwidth of operation; therefore, radiation patterns and characteristics at the level of individual antennas cannot be ignored as these translate directly into the behavior of an array. Careful choice of antenna type and initial efforts in the sub-array design should be seen as a necessary first step in the design of a large line-of-sight MIMO array of superior characteristics.

Comparison of Microstrip W-Band Detectors Based on Zero Bias Schottky-Diodes

This paper presents and discusses three different low-cost microstrip implementations of Schottky-diode detectors in W Band, based on the use of the Zero Bias Diode (ZBD) from VDI (Virginia Diodes, Charlottesville, VA, USA). Designs are based on a previous work of modeling of the ZBD diode. Designs also feature low-cost, easy-to-use tooling substrates (RT Duroid 5880, 5 mils thickness) and even low-cost discrete SMD components such as SOTA resistances (State Of The Art TM miniaturized surface mount resistors), which are modeled to be used well above commercial frequency margins. Intensive use of 3D EM simulation tools such as HFSS TM is done to support microstrip board modeling. Measurements of the three designs fabricated are compared to simulations and discussed.

Design, simulation and implementation of low cost microstrip array antenna for KU–band satellite system

This paper present 32 Element microstrip rectangular patch array antenna for KU-Band. The aim of the design is to achieve low cost, low weight and high gain antenna for the transmissions frequency range of KU – Band satellite system. The paper also present 5 designs for array antenna 2, 4,8,16 and 32 elements and the results comparison between them. The substrate material is FR-4 with 1.58 mm thickens. The simulation made by CST Microwave studio 2017. The size of final design is 85×98.81 mm and the bandwidth is 1.489 GHz. The frequency range of design starting from 13.318 GHz to 14.842 GHz with maximum Gain 13.7 dB. The final design of 32 elements array antenna has been fabricated and compared with the simulation results, a good agreements were obtained and the difference between fabrication and measurements results was due to fabrication and measurements tools tolerance. The fabricated design has been measured using Vector network analyzer ROHDE & SCHWARZ ZVB20.

A Compact Lowpass Filter Using Interdigital Line Resonator with Wide Stopband

A compact (0.14 λg × 0.18 λg), low-cost microstrip lowpass filter of 2 GHz cut-off frequency is presented in this paper. The proposed filter structure is designed using interdigital line resonator (ILR) which makes it compact in size. The inclusion of dumbbell-shaped defected ground structures with the ILR structure offers excellent harmonic suppression and broader attenuation band up to 20 GHz, i.e. stopband rejection is almost 164%. The insertion loss of the filter is lower than 0.3 dB. A modification in J-inverter topology is further proposed to demonstrate the coupling behaviour of the presented ILR unit. The lumped equivalent circuit of the designed ILR-based lowpass filter is derived and simulated. Finally, the proposed microstrip filter is fabricated and measured. A good agreement is found among EM-simulated results, circuit-simulated results and the measured results. Such low-loss, high-performance lowpass filter can be used in surface ship radar and satellite communications.

Ultra-Compact and Wideband V(U)HF 3-dB Power Dividers Consisting of Novel Asymmetric Impedance Transformers

Novel asymmetric impedance transformer (NAIT) containing most of symmetric and asymmetric impedance transformers' properties is proposed for ultra-compact and wideband 3-dB power dividers. All the simulated frequency responses of the NAITs are about the same, regardless of sizes, which is regarded as one of the distinct and unique properties not only for the size reduction with design flexibility but also for the wide bandwidths, considering that the bandwidths of the general passive components are proportional to the sizes. The advantage of the NAITs can also be confirmed by another example that even if the NAIT is three times shorter than the previous one, slightly wider bandwidth can be achieved. To verify the suggested theory, one NAIT power divider is tested at 100 MHz. The total transmission-line sections (TLs) of the power divider are only 14.6° long, and the measured bandwidth is about 58 %, leading to 99.3 % size reduction, compared to the conventional typical ones with 90° TLs. In terms of sizes versus bandwidths, the fabricated NAIT power divider may be regarded as the smallest among those ever recorded, based on the low-cost microstrip technology.

Boxed Ring Resonator for Liquid Dielectric Constant Measurement

The present study describes a compact and low-cost microstrip based resonant sensor that is specially developed for measurements of dielectric constant for liquid and paste at a frequency of 2.45GHz. The sensor utilizes shielded, boxed microstrip annular ring resonator structure, enabling a simple method to place a sample of liquid to be measured. The Transmission Line Model (TLM) of the multilayer system is successfully developed. The inverse algorithm is used to calculate real (e’) and imaginary parts (e”) of the permittivity for the liquid sample with the inputs of the changes in the resonant frequency (fr) and the quality factor (Q). Experimental data is testified against the related theory and compared with the results obtained by other researchers. CST MWS simulation software is used for the optimization of the boxed annular ring and concentric ring resonator structure. The comparison is done for the annular ring and concentric ring resonator boxed structure. Annular ring resonator structure has better accuracy than concentric ring resonator structure. This measurement system indicates high potential towards the development of a portable technique for quality analysis of liquids.

Interdigital Capacitor Based Compact Microstrip Bandpass Filter with Wide Stopband

ABSTRACT A compact, low-cost microstrip bandpass filter (BPF) with low insertion loss and wide attenuation band is presented in this article. The proposed structure consists of multiple interdigital capacitor sections and a T-shaped stub which is connected to the ground using via. The wide stopband response is achieved by the inclusion of defected ground structures (DGS). Addition of these defected ground structures also reduces the circuit size. The designed BPF of centre frequency 0.9 GHz is fabricated, measured, and its lumped equivalent circuit is also obtained. A good agreement is found among IE3D simulated results, circuit simulated results, and the measured results. The obtained results for the proposed bandpass filter (BPF) are −3 dB fractional bandwidth (FBW) of 63% and minimum insertion loss of 0.59 dB. The relative stop band (RSB) rejection is found up to 177% and the normalized circuit size (NCS) is found 0.012. This proposed filter can be used for GSM and other microwave circuitry in wireless communication system.