Conventional terrain-aided navigation (TAN) technique uses an altimeter to locate the position of an aerial vehicle. However, a major problem with a radar altimeter is that its beam (or pulse) footprint on the ground could be large, and therefore the nadir altitude cannot be estimated
accurately. To overcome this difficulty, one may use the nadir-looking synthetic aperture radar (SAR) technique to reduce the along-track beam width, while the cross-track ambiguity is
resolved with the interferometry technique. However, the cross-track resolution is still far from satisfactory, because of the limited aperture size of antennas. Therefore, the usual three-antenna array cannot resolve multiple terrain points in a same range bin, effectively. In this paper, we
propose a technique that can increase the cross-track resolution using a large number of antennas, but in a switched fashion, not raising hardware cost.
SAUSAGE MINKOWSKI SQUARE PATCH ANTENNA FOR GPS APPLICATIONP singh
Square Patch Antennas find wide range in practical modern communication system. The novel idea employed in this paper is to use Sausage Minkowski of square patch antenna as a candidate for using in Global Positioning System (GPS) applications. The antenna has been designed to operate at frequency resonance of 1.575 GHz which is the upper GPS band (L1). The proposed antenna is designed and simulated using CST Studio suite version-2014. The proposed antenna has been simulated on substrate TMM4 of relative permittivity equals to 4.5 and thickness of 1.6 mm. The results are reported in terms of reflection coefficient, VSWR, directivity and gain. According to our results, the antenna at 2nd iteration has gain 4.61dB, VSWR is 1.2 and reduce in area of patch about 42.8% less than 0 iteration. The antenna is more efficient by applying fractal geometry.
Particle Swarm Optimization for the Path Loss Reduction in Suburban and Rural...IJECEIAES
In the present work, a precise optimization method is proposed for tuning the parameters of the COST231 model to improve its accuracy in the path loss propagation prediction. The Particle Swarm Optimization is used to tune the model parameters. The predictions of the tuned model are compared with the most popular models. The performance criteria selected for the comparison of various empirical path loss models is the Root Mean Square Error (RMSE). The RMSE between the actual and predicted data are calculated for various path loss models. It turned out that the tuned COST 231 model outperforms the other studied models.
SAUSAGE MINKOWSKI SQUARE PATCH ANTENNA FOR GPS APPLICATIONP singh
Square Patch Antennas find wide range in practical modern communication system. The novel idea employed in this paper is to use Sausage Minkowski of square patch antenna as a candidate for using in Global Positioning System (GPS) applications. The antenna has been designed to operate at frequency resonance of 1.575 GHz which is the upper GPS band (L1). The proposed antenna is designed and simulated using CST Studio suite version-2014. The proposed antenna has been simulated on substrate TMM4 of relative permittivity equals to 4.5 and thickness of 1.6 mm. The results are reported in terms of reflection coefficient, VSWR, directivity and gain. According to our results, the antenna at 2nd iteration has gain 4.61dB, VSWR is 1.2 and reduce in area of patch about 42.8% less than 0 iteration. The antenna is more efficient by applying fractal geometry.
Particle Swarm Optimization for the Path Loss Reduction in Suburban and Rural...IJECEIAES
In the present work, a precise optimization method is proposed for tuning the parameters of the COST231 model to improve its accuracy in the path loss propagation prediction. The Particle Swarm Optimization is used to tune the model parameters. The predictions of the tuned model are compared with the most popular models. The performance criteria selected for the comparison of various empirical path loss models is the Root Mean Square Error (RMSE). The RMSE between the actual and predicted data are calculated for various path loss models. It turned out that the tuned COST 231 model outperforms the other studied models.
Precise Attitude Determination Using a Hexagonal GPS PlatformCSCJournals
In this paper, a method of precise attitude determination using GPS is proposed. We use a hexagonal antenna platform of 1 m diameter (called the wheel) and post-processing algorithms to calculate attitude, where we focus on yaw to prove the concept. The first part of the algorithm determines an initial absolute position using single point positioning. The second part involves double differencing (DD) the carrier phase measurements for the received GPS signals to determine relative positioning of the antennas on the wheel. The third part consists of Direct Computation Method (DCM) or Implicit Least Squares (ILS) algorithms which, given sufficiently accurate knowledge of the fixed body frame coordinates of the wheel, takes in relative positions of all the receivers and produces the attitude. Field testing results presented in this paper will show that an accuracy of 0.05 degrees in yaw can be achieved. The results will be compared with a theoretical error, which is shown by Monte Carlo simulation to be < 0.001 degrees. The improvement to the current state-of-the-art is that current methods require either very large baselines of several meters to achieve such accuracy or provide errors in yaw that are orders of magnitude greater.
Improved Snr Of Mst Radar Signals By Kaiser-Hamming And Cosh-Hamming Window F...IJERA Editor
In this paper the effect of window shape parameter „α‟ in Kaiser-Hamming and Cosh-Hamming window functions on the signal to noise ratio (SNR) values of the Indian Mesosphere-Stratosphere-Troposphere (MST) radar is computed. The six parts of multibeam observations of the lower atmosphere made by the MST radar are utilized for the analysis of results. Prior to the Fourier transformation, the in-phase and quadrature components of radar echo samples are weighted with proposed windows based on the Kaiser-Hamming and Cosh-Hamming Window functions. The effects of data weighting with the change of the window shape parameter „α‟ of the Kaiser-Hamming and Cosh-Hamming Window functions are given in it. It is noted that the increase of variable window shape parameter „α‟ increases the signal to noise ratio values and a better improvement is reported. For Kaiser-Hamming and Cosh-Hamming Window functions are proposed to analyze the MST radar return signals to obtain optimum values of the window shape parameter. The results shows the improvement of signal to noise ratio of noisy data due to the effect of side lobe reduction and demands for the design of the optimal window functions.
Design and development of a novel fractal antenna for wireless applicationseSAT Journals
Abstract An innovative concept is utilized to develop the fractal antenna by coalesce the Koch prefractal and meander line. This fractal antenna is proposed for multistandard wireless applications. The shape and dimensions of the proposed antenna are chosen to obtain the multiband behaviour as well as miniaturized structure. Initially two different fractal concepts have been chosen through previous research and merged them to obtain more than two resonant frequencies. The proposed design characterizes four bands at resonant frequencies 2.5 GHz, 6.4 GHz, 7.2 GHz and 8.15 GHz with a return loss of -12.05 dB, -16.68 dB, -14.87 dB and -26.51 dB respectively. This design also represents VSWR between the required range of 1 to 2 for the presented resonant frequencies with an appropriate value of gain in dB. The antenna is analysed with Ansoft HFSS-13.0 electromagnetic field solver. Keywords: Microstrip antennas, fractal antennas, miniaturized, multistandard, wireless applications
GPS Instrumental Biases Estimation Using Continuous Operating Receivers NetworkCSCJournals
Precise Total Electron Content (TEC) are required to produce accurate spatial and temporal resolution of Global Ionosphere Maps (GIMs). Receivers and Satellites Instrumental Biases (IBs) are one of the main error sources in estimating precise TEC from Global Positioning Systems (GPS) data. Recently, researchers are interested in developing models and algorithms to compute IBs of receivers and satellites close to those computed from the Ionosphere Associated Analysis Centers (IAAC). Here we introduce a MATLAB code called Multi Station IBs Estimation (MSIBE) to calculate satellites and codeless tracking receivers IBs from GPS data. MSIBE based on spherical harmonic function and geometry free combination of GPS carrier phase and pseudo-range code observations and weighted least square were applied to solve observation equations, to improve estimation of IBs values. There are many factors affecting estimated value of IBs. The premier factor is the observations weighting function which relying on the satellite elevation angle. The second factor concerned with estimating IBs using single GPS Station Precise Point Positioning (PPP) or using GPS network. The third factor is the number of GPS receivers in the network. Results from MSIBE were evaluated and compared with data from IAAC and other codes like M_DCB and ZDDCBE. The results of weighted (MSIBE) least square shows an improvement for estimated IBs, where mean differences from CODE less than 0.746 ns. IBs estimated from Continuous Operating Receivers (CORs) GPS network shows a good agreement with IAAC than IBs estimated from PPP where the mean differences are less than 0.1477 ns and 1.1866 ns, respectively. The mean differences of computed IBs improved by increasing number of GPS stations in the network.
This week at Oceanology Americas we presented a paper on SLAM and Optimal Sensor Fusion and outlined how we have implemented this within our real-time navigation and 3D reconstruction tool, 3D Recon.
We have just assembled two 4,000m rated 3D Recon systems. One of these systems is currently undergoing pressure cycle testing while the other is undergoing extensive burn-in testing to ensure long term viability.
We expect to have test tank data later in March, so if you'd like to receive some sample data sets please let us know at sales@zupt.com.
MINIATURISATION OF PATCH ANTENNA USING NOVEL FRACTAL GEOMETRYIAEME Publication
In the Field of low profile antennamicro strip patch antennas have attracted many researchers due to small sizeand low cost of fabrication. One of trending member of new designs is Fractalantenna. Fractal shapes are recursive/repetitive self-similar geometries, dueto this self-similarity they can provide high gain, multiband, widebandsolutions and design miniature antenna. Fractal shapes are widely used incomputing, analysis and design; recent trends suggest positive outcomes ofusing fractal shapes in electromagnetics and communication system. In thispaper Jerusalem cube fractal shape is introduced in probe fed conventionalpatch antenna for L1 band. A dual band antenna resonating at 1.41 GHz (L) and3.37 (S) GHz, band is constructed using said fractal shape.
RT (Ray Tracing) models are widely used in RAN for channel modelling. Another possible application in
processing chain of base station with multiple purposes: positioning, channel estimation/prediction, radio
resources scheduling and others. In this paper RT positioning technique is addressed for Urban Outdoor
scenario. Proposed robust approach achieves several meters accuracy even in NLOS and multipath
conditions. Developed RT tracking was used for multiuser (MU) precoder prediction and demonstrated
significant capacity gain. Also, this paper discloses practical aspects for achieving high accuracy.
RT (Ray Tracing) models are widely used in RAN for channel modelling. Another possible application in processing chain of base station with multiple purposes: positioning, channel estimation/prediction, radio resources scheduling and others. In this paper RT positioning technique is addressed for Urban Outdoor scenario. Proposed robust approach achieves several meters accuracy even in NLOS and multipath conditions. Developed RT tracking was used for multiuser (MU) precoder prediction and demonstrated significant capacity gain. Also, this paper discloses practical aspects for achieving high accuracy.
Precise Attitude Determination Using a Hexagonal GPS PlatformCSCJournals
In this paper, a method of precise attitude determination using GPS is proposed. We use a hexagonal antenna platform of 1 m diameter (called the wheel) and post-processing algorithms to calculate attitude, where we focus on yaw to prove the concept. The first part of the algorithm determines an initial absolute position using single point positioning. The second part involves double differencing (DD) the carrier phase measurements for the received GPS signals to determine relative positioning of the antennas on the wheel. The third part consists of Direct Computation Method (DCM) or Implicit Least Squares (ILS) algorithms which, given sufficiently accurate knowledge of the fixed body frame coordinates of the wheel, takes in relative positions of all the receivers and produces the attitude. Field testing results presented in this paper will show that an accuracy of 0.05 degrees in yaw can be achieved. The results will be compared with a theoretical error, which is shown by Monte Carlo simulation to be < 0.001 degrees. The improvement to the current state-of-the-art is that current methods require either very large baselines of several meters to achieve such accuracy or provide errors in yaw that are orders of magnitude greater.
Improved Snr Of Mst Radar Signals By Kaiser-Hamming And Cosh-Hamming Window F...IJERA Editor
In this paper the effect of window shape parameter „α‟ in Kaiser-Hamming and Cosh-Hamming window functions on the signal to noise ratio (SNR) values of the Indian Mesosphere-Stratosphere-Troposphere (MST) radar is computed. The six parts of multibeam observations of the lower atmosphere made by the MST radar are utilized for the analysis of results. Prior to the Fourier transformation, the in-phase and quadrature components of radar echo samples are weighted with proposed windows based on the Kaiser-Hamming and Cosh-Hamming Window functions. The effects of data weighting with the change of the window shape parameter „α‟ of the Kaiser-Hamming and Cosh-Hamming Window functions are given in it. It is noted that the increase of variable window shape parameter „α‟ increases the signal to noise ratio values and a better improvement is reported. For Kaiser-Hamming and Cosh-Hamming Window functions are proposed to analyze the MST radar return signals to obtain optimum values of the window shape parameter. The results shows the improvement of signal to noise ratio of noisy data due to the effect of side lobe reduction and demands for the design of the optimal window functions.
Design and development of a novel fractal antenna for wireless applicationseSAT Journals
Abstract An innovative concept is utilized to develop the fractal antenna by coalesce the Koch prefractal and meander line. This fractal antenna is proposed for multistandard wireless applications. The shape and dimensions of the proposed antenna are chosen to obtain the multiband behaviour as well as miniaturized structure. Initially two different fractal concepts have been chosen through previous research and merged them to obtain more than two resonant frequencies. The proposed design characterizes four bands at resonant frequencies 2.5 GHz, 6.4 GHz, 7.2 GHz and 8.15 GHz with a return loss of -12.05 dB, -16.68 dB, -14.87 dB and -26.51 dB respectively. This design also represents VSWR between the required range of 1 to 2 for the presented resonant frequencies with an appropriate value of gain in dB. The antenna is analysed with Ansoft HFSS-13.0 electromagnetic field solver. Keywords: Microstrip antennas, fractal antennas, miniaturized, multistandard, wireless applications
GPS Instrumental Biases Estimation Using Continuous Operating Receivers NetworkCSCJournals
Precise Total Electron Content (TEC) are required to produce accurate spatial and temporal resolution of Global Ionosphere Maps (GIMs). Receivers and Satellites Instrumental Biases (IBs) are one of the main error sources in estimating precise TEC from Global Positioning Systems (GPS) data. Recently, researchers are interested in developing models and algorithms to compute IBs of receivers and satellites close to those computed from the Ionosphere Associated Analysis Centers (IAAC). Here we introduce a MATLAB code called Multi Station IBs Estimation (MSIBE) to calculate satellites and codeless tracking receivers IBs from GPS data. MSIBE based on spherical harmonic function and geometry free combination of GPS carrier phase and pseudo-range code observations and weighted least square were applied to solve observation equations, to improve estimation of IBs values. There are many factors affecting estimated value of IBs. The premier factor is the observations weighting function which relying on the satellite elevation angle. The second factor concerned with estimating IBs using single GPS Station Precise Point Positioning (PPP) or using GPS network. The third factor is the number of GPS receivers in the network. Results from MSIBE were evaluated and compared with data from IAAC and other codes like M_DCB and ZDDCBE. The results of weighted (MSIBE) least square shows an improvement for estimated IBs, where mean differences from CODE less than 0.746 ns. IBs estimated from Continuous Operating Receivers (CORs) GPS network shows a good agreement with IAAC than IBs estimated from PPP where the mean differences are less than 0.1477 ns and 1.1866 ns, respectively. The mean differences of computed IBs improved by increasing number of GPS stations in the network.
This week at Oceanology Americas we presented a paper on SLAM and Optimal Sensor Fusion and outlined how we have implemented this within our real-time navigation and 3D reconstruction tool, 3D Recon.
We have just assembled two 4,000m rated 3D Recon systems. One of these systems is currently undergoing pressure cycle testing while the other is undergoing extensive burn-in testing to ensure long term viability.
We expect to have test tank data later in March, so if you'd like to receive some sample data sets please let us know at sales@zupt.com.
MINIATURISATION OF PATCH ANTENNA USING NOVEL FRACTAL GEOMETRYIAEME Publication
In the Field of low profile antennamicro strip patch antennas have attracted many researchers due to small sizeand low cost of fabrication. One of trending member of new designs is Fractalantenna. Fractal shapes are recursive/repetitive self-similar geometries, dueto this self-similarity they can provide high gain, multiband, widebandsolutions and design miniature antenna. Fractal shapes are widely used incomputing, analysis and design; recent trends suggest positive outcomes ofusing fractal shapes in electromagnetics and communication system. In thispaper Jerusalem cube fractal shape is introduced in probe fed conventionalpatch antenna for L1 band. A dual band antenna resonating at 1.41 GHz (L) and3.37 (S) GHz, band is constructed using said fractal shape.
RT (Ray Tracing) models are widely used in RAN for channel modelling. Another possible application in
processing chain of base station with multiple purposes: positioning, channel estimation/prediction, radio
resources scheduling and others. In this paper RT positioning technique is addressed for Urban Outdoor
scenario. Proposed robust approach achieves several meters accuracy even in NLOS and multipath
conditions. Developed RT tracking was used for multiuser (MU) precoder prediction and demonstrated
significant capacity gain. Also, this paper discloses practical aspects for achieving high accuracy.
RT (Ray Tracing) models are widely used in RAN for channel modelling. Another possible application in processing chain of base station with multiple purposes: positioning, channel estimation/prediction, radio resources scheduling and others. In this paper RT positioning technique is addressed for Urban Outdoor scenario. Proposed robust approach achieves several meters accuracy even in NLOS and multipath conditions. Developed RT tracking was used for multiuser (MU) precoder prediction and demonstrated significant capacity gain. Also, this paper discloses practical aspects for achieving high accuracy.
Performance assessment of antenna array for an unmanned air vehicle IJECEIAES
In this paper, the performance of Linear Antenna Array Element (LAAE) has been evaluated at the Base Station (BS) with a different number of elements for Unmanned Air Vehicle UAV application. The Switched Beam (SB) and Phase Array (PA) have been used as a steering beam mechanism. The beam steering tracker is based on the GPS points of the UAV and the BS. In addition, the Misalignment angle has been analyzed for SB and PA corresponding to the maximum speed of the UAV. The compression between SB and PA in term of Bit Error Rate (BER) vs. Signal to Noise Ratio (SNR) and BER vs. Misalignment angle have been examined by using Matlab. The results show that the PA has better performance than SB in both terms under Additive White Gaussian Noise (AWGN) channel with an interference signal. When the number of the elements is eight provides longer distance than four by the factor (1.5 in SB case and 2 in PA case) and wider Misalignment angle range than twelve by factor (2 in SW case and 3 in PA case). Therefore, it is becoming a useful option for many applications.
Development of patch stack antenna for CP-SAR sensorjournalBEEI
In this paper, we obtain the basic configuration of the left-hand circular polarization (LHCP) array two patches stack triangular truncated microstrip antenna. This construction use the basic corporate feed microstrip-line with modified lossless T-junction power divider on radiating patch for circularly polarized-synthetic aperture radar (CP-SAR) sensor embedded on airspace with compact, small, and simple configuration. The design of Circular Polarization (CP) is realized by truncating the whole three tips and adjusting the parameters of antenna at the resonant frequency, f=5.2 GHz. The results of characteristic performance and S-parameter for the LHCP array two patches stack antenna at the resonant frequency show successively about 7.24 dBic of gain, 1.99 dB of axial ratio (Ar), and -11.43 dB of S-parameter. Moreover, the impedance bandwidth and the 3 dB-Ar bandwidth of this antenna are around 560 MHz (10.77%) and 50 MHz (0.96%), respectively.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will be used in future automotive navigation systems. This system will be a composite of the United States' Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System (GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A further study of this patch antenna illustrates the absolute phase center variation measured in an indoor range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is investigated when integrated into a standard multi-band automotive antenna product. This product is evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using this evaluation file to estimate the receiver position could achieve phase motion error-free result.
DUAL BAND GNSS ANTENNA PHASE CENTER CHARACTERIZATION FOR AUTOMOTIVE APPLICATIONSjantjournal
High-accuracy Global Navigation Satellite System (GNSS) positioning is a prospective technology that will
be used in future automotive navigation systems. This system will be a composite of the United States'
Global Positioning System (GPS), the Russian Federation's Global Orbiting Navigation Satellite System
(GLONASS), China Beidou Navigation Satellite System (BDS) and the European Union’s Galileo. The
major improvement in accuracy and precision is based on (1) multiband signal transmitting, (2) carrier
phase correction, (3) Real Time Kinematic (RTK). Due to the size and high-cost of today’s survey-grade
antenna solutions, this kind of technology is difficult to use widely in the automotive sector. In this paper, a
low-cost small size dual-band ceramic GNSS patch antenna is presented from design to real sample. A
further study of this patch antenna illustrates the absolute phase center variation measured in an indoor
range to achieve a received signal phase error correction. In addition, this low-cost antenna solution is
investigated when integrated into a standard multi-band automotive antenna product. This product is
evaluated both on its own in an indoor range and on a typical vehicle roof at an outdoor range. By using
this evaluation file to estimate the receiver position could achieve phase motion error-free result.
RADAR (RAdio Detection and Ranging) use modulated waveforms and directive antennas to transmit electromagnetic energy into a specific volume in space to search for targets. The targets within the volume reflect echoes back to the radar which are further processed to extract target information. A better SNR (Signal to Noise Ratio) to for radar surveillance is achieved. The results are provided by Matlab simulation.
Data Collection via Synthetic Aperture Radiometry towards Global SystemIJERA Editor
Nowadays it is widely accepted that remote sensing is an efficient way of large data management philosophy. In
this paper, we present a future view of the big data collection by synthetic aperture radiometry as a passive
microwave remote sensing towards building a global monitoring system. Since the collected data may not have
any value, it is mandatory to analyses these data in order to get valuable and beneficial information with respect
to their base data. The collected data by synthetic aperture radiometry is one of the high resolution earth
observation, these data will be an intensive problems, Meanwhile, Synthetic Aperture Radar able to work in
several bands, X, C, S, L and P-band. The important role of synthetic aperture radiometry is how to collect data
from areas with inadequate network infrastructures where the ground network facilities were destroyed. The
future concern is to establish a new global data management system, which is supported by the groups of
international teams working to develop technology based on international regulations. There is no doubt that the
existing techniques are so limited to solve big data problems totally. There is a lot of work towards improving 2-
D and 3-D SAR to get better resolution.
STUDY OF ARRAY BI-CONICAL ANTENNA FOR DME APPLICATIONSijwmn
This paper introduces a new configuration of array bi-conical antenna to enhance the gain of an antenna for Distance Measuring Equipment (DME) avionic system. Due to its large size, the antenna can be placed in terrestrials DME stations. The antenna consists of the bi-conical elements placed in a linear configuration. The simulated maximum gain is 10.2dB, the antenna operates in the DME band (960 – 1215 MHz). Al the simulations are performed with CADFEKO a Method of Moments based Solver.
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
2. 152 Computer Science & Information Technology (CS & IT)
we propose a technique that can increase the cross-track resolution using a large number of
antennas, but in a switched fashion, not raising hardware cost.
Figure 1: Multipoint-terrain-aided navigation
Figure 2 shows the flight geometry. We assume that there is a separate single transmit antenna,
and N receive antennas. Also assume that there are L range bins and M coherent pulses. Then,
we can find the range r , along-track angle a
θ and the cross-track angle c
θ to a given terrain
point, respectively by measuring the echo return time, Doppler and angle of arrival (AOA).
Figure 2: Flight geometry
Fig. 3 shows a 3D data cube, which represents a point target response after the range deramping
operation.
Figure 3: Deramped raw-data for a point target
3. Computer Science & Information Technology (CS & IT) 153
The point target position in the 3D can be found by a 3D fast Fourier transform (DFT) of the data
cube. The 3D data cube for actual terrain which has an infinite number of point targets will be the
superposition of individual point target response, and the reconstruction of the terrain profile in
Fig. 1 can be carried out by a 3D FFT of the data cube. From the reconstructed terrain profile, we
can estimate the position and attitude of the aerial vehicle.
2. THE SWITCHED ARRAY ALTIMETER
To obtain an accurate terrain profile, the number of antennas N must be large, resulting in a
large number of RF chains. However, it turns out that a reasonably accurate terrain profile can be
found by selecting a small number of K N= antennas, randomly at each pulse. Fig. 4 shows the
raw data when only 12% (Fig 4b) and 6% (Fig 4b) of antennas are selected.
Figure 4. Raw data when (4a) 32K N= = , (4b) 3, 32K N= = , (4c) 2, 32K N= =
To find the cross-track angle and range to the target, we need to compute the 2D FFTs of the raw
data in Fig 4. The results are shown in Fig. 5. Note that the raw data obtained with switching
produce reasonably accurate angle and range estimates.
5. Computer Science & Information Technology (CS & IT) 155
Figure 5. Recovered point target from the raw data obtained by switching. The three plots correspond to the
three raw data in Figure 4.
3. TRACKING ALGORITHM
We use the usual 15-state Kalman filter [5], [9] to find the attitude and position of the vehicle. In
particular, the time-update is carried out using the inertial measurement unit (IMU) data, and the
measurement-update is done by comparing the reconstructed terrain profile with the on-board
DEM (See Fig. 6). The estimated terrain profile will be particularly accurate at the mountain
ridges, which are marked with white curves in Fig 1. Referring to the on-board DEM, we select
multiple points (A, B, C in Fig 1) on the ridges, and determine the angles a
θ s and c
θ s. Then we
determine the ranges r s to these points. These measurements are then compared with the
predicted measurements ˆr to get innovation e .
Figure 6. Block diagram of the INS
6. 156 Computer Science & Information Technology (CS & IT)
Fig 7 shows the detailed computational steps of the proposed inertial navigation system (INS).
Our preliminary simulation results show that the convergence of the state estimate is quite faster
with the proposed multi-point TAN than with the usual single point TAN.
Figure 7. The proposed INS
4. CONCLUSIONS
We have proposed a switched antenna interferometric SAR TAN algorithm that can overcome
the drawback of conventional interferometric SAR TAN. The proposed technique uses a small
number of RF channels which are switched to a large number of antennas. Therefore, our
proposed technique will give a high cross - track resolution comparable to the along-track SAR-
based resolution, not raising hardware cost much.
ACKNOWLEDGEMENTS
This work was supported in part by Hanwha Thales in 2014-2015.
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[6] J. Curlander and R. McDonough, Stnthetic Aperture Radar, Systems and Signal Processing, John
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