GPS Applications Research Articles

Dual-resonance microwave probe for magnetic field mapping

This paper introduces a dual-resonance probe for mapping magnetic fields in electromagnetic compatibility (EMC) applications. The probe, consisting of a circular loop loaded with a 6-turn circular spiral, exhibits two resonant modes via capacitive coupling, resonating at 1.158 GHz and 1.582 GHz to cover L1 and parts of the L5 band. Designed for GPS applications, the presented equivalent circuit model of the probe simplifies its design. The probe maps the orthogonal magnetic field component at its resonant frequencies. Measurements, taken while scanning over a short-circuited microstrip line and a rat-race hybrid coupler, closely match their simulated orthogonal magnetic field component. The proposed probe offers advancements in sensitivity enhancing EMC in various electronic systems.

Performance Evaluation of Matching Networks in Low Noise Amplifiers for GPS Application

Performance Evaluation of Matching Networks in Low Noise Amplifiers for GPS Application

Robust Multi-Band DNG metamaterial absorber for GPS (L1), ISM, and 5G application with Enhanced polarization and angle stability

This research introduces a triple-band metamaterial absorber characterized by insensitivity to both polarization and incident angles. The structure includes square ring resonators on the upper side and a continuous metal ground on the lower side, separated by an FR4 substrate. At the lowest operating frequency, the unit cell’s thickness, and length measure 0.0128λ and 0.156λ, respectively. Under normal incidence, the proposed absorber demonstrates three clear absorption peaks at 1.56, 2.43, and 3.36 GHz, achieving absorption rates of 98 %, 99 %, and 97 %, respectively. The absorption response exhibits variation with incident angles up to 70° for both TM and TE polarizations due to its high-level symmetry. This configuration attains negative permittivity and permeability suitable for operational frequencies in the L-band and S-band. The study examines the electric field, impedance, and surface current to provide additional evidence for the absorption analysis. A validated RLC circuit equivalent to the proposed structure has been confirmed using Advanced Design System (ADS). The results indicate a slight deviation, especially at frequencies beyond the resonance frequencies. The structure underwent fabrication and testing in an anechoic chamber, revealing a strong correlation between the simulated and measured results. The suggested absorber holds promise for ISM applications, radar systems, sensing technologies, and energy harvesting systems.

High‐performance balanced dual‐band bandpass filter with controllable bandwidth and frequency ratio

AbstractIn this study, a novel high‐performance balanced dual‐band bandpass filter (BPF) with controllable bandwidth and frequency ratio is proposed. The symmetrical dual‐band bandpass characteristics on both sides of the center frequency f0 can be achieved by cascading two one‐wavelength edge‐coupled ring resonators through coupling. To suppress the common‐mode (CM) noises, a high‐performance balanced dual‐band BPF is designed and analyzed. The elements affecting the controllable filtering bandwidth and frequency ratio are discussed. For practical verification, a microstrip prototype for GPS applications is manufactured and measured with great out‐of‐band rejection and excellent CM suppression.

Design of Compact Size Tri-Band Stacked Patch Antenna for GPS and IRNSS

Abstract: This paper introduces a low-profile, compact tri-band microstrip patch antenna designed for GPS and IRNSS applications. The proposed antenna operates at frequencies of 1.57 GHz, 1.22 GHz, and 1.77 GHz. The antenna configuration consists of a patch antenna with a slip slot or manderline to generate three frequency bands while maintaining an acceptable radiation pattern. The focus of the study is to enhance the antenna's gain across all three frequency bands. This design aims to offer a versatile solution for navigation systems, leveraging the tri-band capability to accommodate different satellite signals and improve overall performance in GPS and IRNSS applications.

Homogeneous and Heterogeneous Multicore Systems

Multicore systems have gained significant importance in the Automotive industry due to data- intensive applications, such as image processing, high- speed process, and GPS application. It enables manufacturers to build smaller chips, simplifying board architecture and routing, reducing power consumption and cost and increasing programmability. Multicore platforms are segregated into two categories namely Homogeneous (symmetric) and Heterogeneous (asymmetric) multicore systems. In Homogeneous systems, all cores are the same, including frequencies, cache sizes and functions. In Heterogeneous systems, different cores operate with different frequencies, cache sizes and functions. In this paper, we are going to discuss various aspects of homogeneous and heterogeneous multicore architectures like number and level of caches, interconnection of the cores, Physical and Temporal isolation, Energy Efficiency, Concurrency, Performance, Reliability and Robustness along with the evaluation of these two architectures for applications based on the above-mentioned aspects.

GPS-Based Precise Orbit Determination of LEO Satellites Using Space-Based Double-Differenced Observations

One of the important GPS applications in space is precise orbit determination (POD) of Low-Earth Orbit (LEO) satellites. Thousands of LEO satellites are currently in orbit. One of the challenges is how to efficiently and precisely determine the orbits to satisfy the relative and absolute accuracy needs of missions. Currently, GPS-based POD of LEO satellites can be performed using either un-differenced (UD) or ground-based double-differenced (DD) observations. The UD POD needs both precise GPS satellite orbits and clocks; the DD POD needs not only the precise orbits, but also global ground reference receivers. Therefore, the GPS-based LEO POD is based on either global ground stations or precise GNSS clocks, which are not convenient for near real-time or real-time data processing. The GPS orbits can be precisely predicted in certain time; the clocks are not. For some formation flying satellite missions (two or more LEO satellites), the absolute orbit accuracy requirements are not as stringent as the relative requirements. The problem is how to perform LEO POD without global station data and precise GPS clocks in near real-time or real-time to achieve the mission orbit accuracy requirement. Based on this motivation, we investigated the GPS-based LEO POD using space-based DD observations without using global ground station GPS data and precise GPS clock products. For this study, we processed the real GPS observations from two LEO satellites. The absolute and relative orbit accuracy is assessed using several tests, including analysis of the orbit fits, external orbit comparisons, Satellite Laser Ranging (SLR) and K-band Ranging (KBR) residuals.

A Literature Review of Exploratory Analysis of Geolocational Data

Geospatial data is a key part of the digital age. It contains geographic coordinates and location information of people, vehicles, objects and natural phenomena. The rapid growth in its use is due to smartphones, GPS, social media and various location-based applications. This has led to a new paradigm shift in how data is used across industries. This article looks at the multifaceted role of geolocation data in today's society and examines how important it is in the development and change of various industries in today's world. Geospatial data plays a key role in the digital age and the birth of the Internet of Things. In addition to smooth navigation, it also helps industries better allocate resources, improve decision-making and increase overall efficiency. This report explores the growing importance of spatial data and its critical role in urban planning, transportation, environmental monitoring and surveillance, marketing, and public safety

Erratum to A dual band compact circularly polarized antenna for GPS applications

Erratum to A dual band compact circularly polarized antenna for GPS applications

Performance evaluation of planar dipole antenna for smart home applications

In a Smart Home wireless module, the antenna generally occupies one-third of the total circuit advances in the Internet of Things (IoTs). Dipole antenna comes in various shapes, but the planar antenna is the most suitable and attractive design for the IoTs application in Smart Homes because it is smaller in size and has a thin profile, making it suitable for mounting on portable equipment. In this research, two antennae, Meandered Dipole and Wideband Planar Antenna, were designed using Advance Design System (ADS) software on a PCB size of 18.8 mm × 43.2 mm, FR4 substrate with 4.6 dielectric constant and 0.8 mm thickness using copper metal as the conducting element. The transmission line has designed width of 1.25 mm, resulting in a typical line impedance of 50 Ω. A comparison of the analysis of simulation and measurement results from feeding port 1 of the Meandered PIFA Antenna shows a better performance of 95.43% efficiency with a gain of 2.54391dBi and a return loss of −24.49 dB at resonant frequency of 2.4 GHz than that from feeding port 2 whose efficiency was only 73.99%. Whereas, the wideband planar antenna shows an average bandwidth of 93.91% from 1.3 to 2.4 GHz. This range covers the GPS applications, the 2.4 GHz ISM band, and the general WCDMA and the LTE 3GPP bands useable for smart home and IoT applications. The proposed antenna provides low power operation, extended range and compact, cost-effective designs to support vendor's customers, and make quality of life smarter and more economical with the use of the smart home device.

A dual band compact circularly polarized antenna for GPS applications

AbstractA novel dual band antenna with right‐hand circular polarization (RHCP) is fabricated. It consists of a T‐shaped parasitic element on the backside of T‐shaped patch (TSP) and a ground plane. The design comprises a rectangular and CPW fed clearance in the ground plane. The placing of a TSP and connecting rectangular stubs to the ground plane is used to achieve GPS L5 and L2 bands. Circular polarization in GPS L5 and L2 bands is produced by rectangular horizontal stubs and F‐shaped slots (FSS), respectively. The measured results show 34 MHz (1.160–1.194 GHz) and 57 MHz (1.207–1.260 GHz) –10 dB impedance bandwidth and 3‐dB axial ratio bandwidths are 10 MHz (1.174–1.184 GHz) and 10 MHz (1.223–1.233 GHz). It also displays a minimum axial ratio of 1.35 and 0.34 dB with broad beamwidth (>100°) essential for the GPS applications. The final design is verified in the experiment. The advantages of the proposed design are compact size, simple structure, and broad beamwidth.

Design of High Selectivity Compact Dual-Band Bandpass Filter With Seven Transmission-Zeros for GPS and WiMAX Applications

A miniaturized Y-shaped dual-band bandpass filter with multiple transmission zeros/poles is presented in this work. The proposed filter configuration comprises series coupled lines, shunt cascaded coupled line and parallel open stubs, and stepped impedance resonators. Analysis of the proposed filter is executed using a circuit simulator, and the magnitude and bandwidth variations have been studied. Equations for transmission zero frequencies have been derived and verified based on lossless transmission line theory and even-odd mode analysis to validate the proposed filter configuration. A prototype operating at 1.38 GHz (GPS) and 3.4 GHz (Wi-Max) applications is fabricated and experimented. The final prototype occupies a compact area of 0.33λg × 0.20λg, where λg is the guided wavelength at the first band (1.38GHz). The experimental results show that the roll-off rate for the first and second passbands is 212.5 and 188 dB/GHz, respectively, indicating high selectivity. The insertion loss is better than 20 dB indicating good isolation between the two passbands.

A Circularly Polarized Stacked Patch Antenna for Dual Band L1 & L2 GPS Applications

A Circularly Polarized Stacked Patch Antenna for Dual Band L1 & L2 GPS Applications

Design and Modelling of a Compact Triband Passband Filter for GPS, WiMAX, and Satellite Applications with Multiple Transmission Zero’s

Designing microwave filters with high selectivity and sharp roll-off between the stop and pass bands can be challenging due to the complex nature of the R.F. signals and the requirements for achieving high performance in a limited physical space. To achieve a high selectivity and sharp roll-off rate, this paper presents a compact filter with a triple passband response. The two different passbands at 1.57 GHz and 3.5 GHz are achieved using a step impedance resonator (SIR) with metallic slots perturbation added to the lower corner of the high impedance section of the SIRs, which helps to enhance the filter’s selectivity and size reduction greatly. The embedded L-shaped structure originates a third passband at 4.23 GHz, resulting in a triband response with eight transmission zeros below and above the passbands at 1.22/1.42/1.98/3.18/3.82/3.98/4.38/4.53 GHz, respectively. The prototype has low signal attenuation of <1.2 dB and high signal reflection of >25 dB for the three passbands. The fractional bandwidths achieved are 2.54%, 4.2%, and 1.65% at 1.57/3.57/4.23 GHz, respectively, with rejection levels in the stopband greater than 15 dB. Lastly, the structure is fabricated on RO-4350B PCB and observed good matching between experimental and measured results. This demonstrates that the prototype can be successfully implemented in real-world applications such as GPS, WiMAX, and Satellite systems. The area occupied by the filter on a substrate or in a circuit is 0.31 λg × 0.24 λg, where λg is the guided wavelength of the material calculated at the lowest frequency.

Dual-Band and Wideband Bandpass Filters Using Coupled Lines and Tri-Stepped Impedance Stubs.

In this paper, two bandpass filters-one with a dual-band response and the other with a wideband response-were designed, implemented, and experimented with. The filters are based on the novel combination of series coupled lines and tri-stepped impedance stubs. However, coupled lines along with tri-stepped impedance open stubs (TSIOSs) give a third-order dual passband response. The advantage of dual-band filters using coupled lines and TSIOSs is that they have wide passbands that are close together and separated by a single transmission zero. In contrast, the inclusion of tri-stepped impedance short-circuited stubs (TSISSs) instead of TSIOSs provides a fifth-order wide passband response. The advantage of wideband bandpass filters using coupled lines and TSISSs is that they have a very good selectivity factor. Theoretical analysis was carried out to validate both filter configurations. The tested bandpass filter using coupled lines and TSIOS units had two close wide passbands operating at 0.92 and 1.52 GHz center frequencies, respectively. The dual-band bandpass filter was implemented to operate in GSM and GPS applications. The first passband had a 3 dB fractional bandwidth (FBW) of 38.04%, while the second passband had a 3 dB FBW of 22.36%. The experimental result of the wideband bandpass filter (with coupled lines and TSISS units) had a center frequency of 1.51 GHz with a 3 dB fractional bandwidth of 62.91% and a selectivity factor of 0.90. A good congruence was demonstrated between the full-wave simulated and tested results for both filters.

Analysing the Impact of Substrate Thickness on Antenna Performance for GPS Application

A microstrip patch antenna is a popular choice of antenna for use in the L band frequency range. They also have good radiation characteristics, making them ideal for receiving and transmitting low-power radio frequency signals. The proposed compact antenna is meant for GPS applications covering the L1 band. The antenna is designed involving the Rogers’s substrate having a dielectric constant of 2.2. The design is based on circular microstrip patch structure with inset feed technique. The selection of the dielectric material and its thickness is very crucial in designing microstrip patch antenna. This paper also explains how antenna performance is improved by varying the thickness of the substrate. The radiation pattern, return loss, gain, directivity, VSWR and efficiency are obtained using EM Simulation and the results are compared for various designs structures. It is inferred that as the thickness of the substrate increases, the performance of the antenna also gets better.

FENOMENA KECURANGAN PEMESANAN PADA JASA TRANSPORTASI ONLINE DALAM PERSPEKTIF FRAUD TRIANGLE

Abstract
 The background of this research is that online transportation service providers found fraud committed by online transportation drivers, using fake GPS applications, making fictitious orders, and giving the highest star rating. This study aims to analyze the effect of internal control, morality, and pressure on fraudulent ordering behavior in online transportation services. This study uses a quantitative approach. The sampling technique was purposive sampling with a total sample of 100 respondents. The data type is primary data using a questionnaire tested by multiple regression analysis. The study results show that the variables of internal control, morality, and pressure influence online transportation services' fraudulent ordering behavior in Pontianak.

A Conformal Wearable Antenna Based on Artificial Magnetic Conductor for GPS Applications

A Conformal Wearable Antenna Based on Artificial Magnetic Conductor for GPS Applications

Design of a Circularly Polarized High-Gain Patch Antenna Using a Higher-Order Mode With a Heterogeneous Substrate Layer for GPS Applications

Design of a Circularly Polarized High-Gain Patch Antenna Using a Higher-Order Mode With a Heterogeneous Substrate Layer for GPS Applications

Simulation and design of the circular polarization microstrip antenna with CSRR metamaterial structure

This paper has discussed the design of a circular polarized microstrip single patch antenna using a complementary split-ring resonator (CSRR) placed in the patch section. The design used an epoxy FR4 substrate with a thickness of 1.6 mm. Antenna specifications that resonate at a frequency of 1.57 GHz are very supportive for GPS applications. The design is carried out with the AWR simulator. The implementation of CSSR metamaterial structure in the patch was successful in improving the design performance compared to the design without using CSRR. Based on the simulation results, the minimum return loss is -40.92 dB at a frequency of 1.57 GHz and an axial ratio below 3 is achieved for the frequency range of 1.56 – 1.59 GHz. Reduction of substrate and patch dimensions was achieved by 36.5% and 46.9%, respectively.