GPS uses a network of satellites to enable receivers on the ground to calculate their precise location. It consists of three segments - the space segment contains 24 satellites in six orbital planes that continuously transmit positioning and timing data; the control segment monitors and maintains the satellites from several ground stations; and the user segment comprises any GPS receiver on the ground, at sea, or in the air that utilizes the satellite signals to determine its coordinates. GPS has both military and civilian applications ranging from navigation to precision agriculture to disaster relief.
Global Positioning System (GPS) is the only system today able to show one’s own position on the earth any time in any weather, anywhere. This paper addresses this satellite based navigation system at length. The different segments of GPS viz. space segment, control segment, user segment are discussed. In addition, how this amazing system GPS works, is clearly described. The various errors that degrade the performance of GPS are also included. DIFFERENTIAL GPS, which is used to improve the accuracy of measurements, is also studied. The need, working and implementation of DGPS are discussed at length. Finally, the paper ends with advanced application of GPS.
The Global Positioning System (GPS), originally Navstar GPS,[1][2] is a space-based radionavigation system owned by the United States government and operated by the United States Air Force. It is a global navigation satellite system that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites
Global positioning system and its mathematical form.
By Mustahsan Khan _ BS(physics-Nanotechnology) (International Islamic University Islamabad) Pakistan.
Global Positioning System (GPS) is the only system today able to show one’s own position on the earth any time in any weather, anywhere. This paper addresses this satellite based navigation system at length. The different segments of GPS viz. space segment, control segment, user segment are discussed. In addition, how this amazing system GPS works, is clearly described. The various errors that degrade the performance of GPS are also included. DIFFERENTIAL GPS, which is used to improve the accuracy of measurements, is also studied. The need, working and implementation of DGPS are discussed at length. Finally, the paper ends with advanced application of GPS.
The Global Positioning System (GPS), originally Navstar GPS,[1][2] is a space-based radionavigation system owned by the United States government and operated by the United States Air Force. It is a global navigation satellite system that provides geolocation and time information to a GPS receiver anywhere on or near the Earth where there is an unobstructed line of sight to four or more GPS satellites
Global positioning system and its mathematical form.
By Mustahsan Khan _ BS(physics-Nanotechnology) (International Islamic University Islamabad) Pakistan.
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.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
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.
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.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
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.
Water scarcity is the lack of fresh water resources to meet the standard water demand. There are two type of water scarcity. One is physical. The other is economic water scarcity.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
The Benefits and Techniques of Trenchless Pipe Repair.pdf
GPS.ppt
1.
2. Overview
Official name of GPS is NAVigational Satellite Timing
And Ranging Global Positioning System (NAVSTAR
GPS)
First developed by the United States Department of
Defense
Consists of two dozen GPS satellites in medium Earth
orbit (The region of space between 20000km and
35,786 km)
3. Overview
Made up of two dozen satellites working in unison are
known as a satellite constellation
This constellation is currently controlled by the United
States Air Force 50th Space Wing
It costs about $750 million to manage and maintain the
system per year
Mainly used for navigation, map-making and
surveying
4. Operation Overview
A GPS receiver can tell its own position by using the
position data of itself, and compares that data with 3 or
more GPS satellites.
To get the distance to each satellite, the GPS transmits a
signal to each satellite.
The signal travels at a known speed.
The system measures the time delay between the signal
transmission and signal reception of the GPS signal.
The signals carry information about the satellite’s location.
Determines the position of, and distance to, at least three
satellites, to reduce error.
The receiver computes position using trilateration.
6. GPS Functionality
GPS systems are made up of 3 segments
Space Segment (SS)
Control Segment (CS)
User Segment (US)
7. Space Segment
GPS satellites fly in circular orbits at an altitude of
20,200 km and with a period of 12 hours.
Powered by solar cells, the satellites continuously
orient themselves to point their solar panels toward
the sun and their antenna toward the earth.
Orbital planes are centered on the Earth
Each planes has about 55° tilt relative to Earth's
equator in order to cover the polar regions.
8. Space Segment
Each satellite makes two complete orbits each sidereal
day.
Sidereal - Time it takes for the Earth to turn 360 degrees
in its rotation
It passes over the same location on Earth once each day.
Orbits are designed so that at the very least, six
satellites are always within line of sight from any
location on the planet.
9. Space Segment
There are currently 30 actively broadcasting satellites
in the GPS constellation.
A non-uniform arrangement improves the reliability
and availability of the system over that of a uniform
system, when multiple satellites fail
This is possible due to the number of satellites in the
air today
10. Control Segment
The CS consists of 3 entities:
Master Control System
Monitor Stations
Ground Antennas
11. Master Control Station
The master control station, located at Falcon Air Force
Base in Colorado Springs, Colorado, is responsible for
overall management of the remote monitoring and
transmission sites.
GPS ephemeris is the tabulation of computed
positions, velocities and derived right ascension and
declination of GPS satellites at specific times for
eventual upload to GPS satellites.
12. Monitor Stations
Six monitor stations are located at Falcon Air Force
Base in Colorado, Cape Canaveral, Florida, Hawaii,
Ascension Island in the Atlantic Ocean, Diego Garcia
Atoll in the Indian Ocean, and Kwajalein Island in the
South Pacific Ocean.
Each of the monitor stations checks the exact altitude,
position, speed, and overall health of the orbiting
satellites.
13. Monitor Stations
The control segment uses measurements collected by
the monitor stations to predict the behavior of each
satellite's orbit and clock.
The prediction data is up-linked, or transmitted, to the
satellites for transmission back to the users.
The control segment also ensures that the GPS satellite
orbits and clocks remain within acceptable limits. A
station can track up to 11 satellites at a time.
14. Monitor Stations
This "check-up" is performed twice a day, by each
station, as the satellites complete their journeys
around the earth.
Variations such as those caused by the gravity of the
moon, sun and the pressure of solar radiation, are
passed along to the master control station.
15. Ground Antennas
Ground antennas monitor and track the satellites from
horizon to horizon.
They also transmit correction information to
individual satellites.
16. User Segment
The user's GPS receiver is the US of the GPS system.
GPS receivers are generally composed of an antenna,
tuned to the frequencies transmitted by the satellites,
receiver-processors, and a highly-stable clock,
commonly a crystal oscillator).
They can also include a display for showing location
and speed information to the user.
A receiver is often described by its number of channels
this signifies how many satellites it can monitor
simultaneously. As of recent, receivers usually have
between twelve and twenty channels.
17. User Segment (continued)
Using the RTCM SC-104 format, GPS receivers may
include an input for differential corrections.
This is typically in the form of a RS-232 port at 4,800 bps
speed. Data is actually sent at a much lower rate, which
limits the accuracy of the signal sent using RTCM.
Receivers with internal DGPS receivers are able to
outclass those using external RTCM data.
18. Navigational Systems
GPS satellites broadcast three different types of data in
the primary navigation signal.
Almanac – sends time and status information about the
satellites.
Ephemeris – has orbital information that allows the
receiver to calculate the position of the satellite.
This data is included in the 37,500 bit Navigation Message,
which takes 12.5 minutes to send at 50 bps.
19. Navigational Systems (cont’d)
Satellites broadcast two forms of clock information
Coarse / Acquisition code (C/A) - freely available to the
public. The C/A code is a 1,023 bit long pseudo-random
code broadcast at 1.023 MHz, repeating every
millisecond.
Restricted Precise code (P-code) - reserved for military
usage. The P-code is a similar code broadcast at 10.23
MHz, but it repeats only once a week. In normal
operation, the anti-spoofing mode, the P code is first
encrypted into the Y-code, or P(Y), which can only be
decrypted by users a valid key.
20. GPS Frequencies
L1 (1575.42 MHz) - Mix of Navigation Message, coarse-
acquisition (C/A) code and encrypted precision P(Y)
code.
L2 (1227.60 MHz) - P(Y) code, plus the new L2C code
on the Block IIR-M and newer satellites.
L3 (1381.05 MHz) - Used by the Defense Support
Program to signal detection of missile launches,
nuclear detonations, and other applications.
21. GPS Proposed Frequencies
L4 (1379.913 MHz) - Being studied for additional
correction to the part of the atmosphere that is ionized
by solar radiation.
L5 (1176.45 MHz) – To be used as a civilian safety-of-
life (SoL) signal.
Internationally protected range for aeronautical
navigation.
The first satellite that using this signal to be launched in
2008.
22. Position Calculation
The coordinates are calculated according to the World
Geodetic System WGS84 coordinate system.
The satellites are equipped with atomic clocks
Receiver uses an internal crystal oscillator-based clock
that is continually updated using the signals from the
satellites.
Receiver identifies each satellite's signal by its distinct
C/A code pattern, then measures the time delay for
each satellite.
23. Position Calculation (cont’d)
The receiver emits an identical C/A sequence using the
same seed number the satellite used.
By aligning the two sequences, the receiver can
measure the delay and calculate the distance to the
satellite, called the pseudorange.
Orbital position data from the Navigation Message is
used to calculate the satellite's precise position.
Knowing the position and the distance of a satellite
indicates that the receiver is located somewhere on the
surface of an imaginary sphere centered on that
satellite and whose radius is the distance to it.
24. Position Calculation (cont’d)
When four satellites are measured at the same time,
the point where the four imaginary spheres meet is
recorded as the location of the receiver.
Earth-based users can substitute the sphere of the
planet for one satellite by using their altitude. Often,
these spheres will overlap slightly instead of meeting
at one point, so the receiver will yield a mathematically
most-probable position.
25. Issues That Affect Accuracy
Changing atmospheric conditions change the speed of
the GPS signals as they pass through the Earth's
atmosphere and ionosphere.
Effect is minimized when the satellite is directly
overhead
Becomes greater for satellites nearer the horizon, since
the signal is affected for a longer time.
Once the receiver's approximate location is known, a
mathematical model can be used to estimate and
compensate for these errors.
26. Issues That Affect Accuracy (cont’d)
Clock Errors can occur when, for example, a GPS
satellite is boosted back into a proper orbit.
The receiver's calculation of the satellite's position will
be incorrect until it receives another ephemeris update.
Onboard clocks are accurate, but they suffer from partial
clock drift.
27. Issues That Affect Accuracy (cont’d)
GPS Jamming can be used to limit the effectiveness of
the GPS signal
For example, it is believed GPS guided missles have been
misled to attack non-target locations in the war in
Afghanistan.
The stronger the jamming signal, the more interference
can be caused to the GPS signal.
28. Issues That Affect Accuracy (cont’d)
GPS signals can also be affected by multipath issues
Radio signals reflect off surrounding objects at a
location. These delayed signals can cause inaccuracy.
Less severe in moving vehicles. When the GPS antenna
is moving, the false solutions using reflected signals
quickly fail to converge and only the direct signals result
in stable solutions.
29. Methods of Improving Accuracy
Precision monitoring
Dual Frequency Monitoring
Refers to systems that can compare two or more signals
These two frequencies are affected in two different ways. How
they are affected can be predicted however
After monitoring these signals, it’s possible to calculate what
the error is and eliminate it
Receivers that have the correct decryption key can decode the
P(Y)-code transmitted on signals to measure the error.
30. Methods of Improving Accuracy (cont’d)
Carrier-Phase Enhancement (CPGPS)
CPGPS uses the L1 carrier wave, which has a period 1000 times
smaller than that of the C/A bit period, to act as an additional
clock signal and resolve uncertainty.
The phase difference error in the normal GPS amounts to
between 2 and 3 meters (6 to 10 ft) of ambiguity.
CPGPS works to within 1% of perfect transition to reduce the
error to 3 centimeters (1 inch) of ambiguity.
By eliminating this source of error, CPGPS coupled with DGPS
normally realizes between 20 and 30 centimeters (8 to 12
inches) of absolute accuracy.
31. Methods of Improving Accuracy (cont’d)
Relative Kinematic Positioning (RKP)
Determination of range signal can be resolved to an accuracy
of less than 10 centimeters (4 in).
Resolves the number of cycles in which the signal is
transmitted and received by the receiver.
Accomplished by using a combination of DGPS correction
data, transmitting GPS signal phase information and
ambiguity resolution techniques via statistical tests —
possibly with processing in real-time.
32. Methods of Improving Accuracy (cont’d)
Augmentation
Relies on external information being integrated into the
calculation process.
Some augmentation systems transmit additional
information about sources of error.
Some provide direct measurements of how much the
signal was off in the past
Another group could provide additional navigational or
vehicle information to be integrated in the calculation
process.
33. Applications – Military
Military GPS user equipment has been integrated into
fighters, bombers, tankers, helicopters, ships,
submarines, tanks, jeeps, and soldiers' equipment.
In addition to basic navigation activities, military
applications of GPS include target designation of
cruise missiles and precision-guided weapons and
close air support.
To prevent GPS interception by the enemy, the
government controls GPS receiver exports
GPS satellites also can contain nuclear detonation
detectors.
34. Applications – Civilian
Automobiles are often equipped GPS receivers.
They show moving maps and information about your
position on the map, speed you are traveling, buildings,
highways, exits etc.
Some of the market leaders in this technology are
Garmin and TomTom, not to mention the built in GPS
navigational systems from automotive manufacturers.
35. Applications – Civilian (cont’d)
For aircraft, GPS provides
Continuous, reliable, and accurate positioning
information for all phases of flight on a global basis,
freely available to all.
Safe, flexible, and fuel-efficient routes for airspace
service providers and airspace users.
Potential decommissioning and reduction of expensive
ground based navigation facilities, systems, and services.
Increased safety for surface movement operations made
possible by situational awareness.
36. Applications – Civilian (cont’d)
Agriculture
GPS provides precision soil sampling, data collection,
and data analysis, enable localized variation of chemical
applications and planting density to suit specific areas of
the field.
Ability to work through low visibility field conditions
such as rain, dust, fog and darkness increases
productivity.
Accurately monitored yield data enables future site-
specific field preparation.
37. Applications – Civilian (cont’d)
Disaster Relief
Deliver disaster relief to impacted areas faster, saving
lives.
Provide position information for mapping of disaster
regions where little or no mapping information is
available.
Example, using the precise position information
provided by GPS, scientists can study how strain builds
up slowly over time in an attempt to characterize and
possibly anticipate earthquakes in the future.
38. Applications – Civilian (cont’d)
Marine applications
GPS allows access to fast and accurate position, course,
and speed information, saving navigators time and fuel
through more efficient traffic routing.
Provides precise navigation information to boaters.
Enhances efficiency and economy for container
management in port facilities.
39. Applications – Civilian (cont’d)
Other Applications not mentioned here include
Railroad systems
Recreational activities (returning to the same fishing
spot)
Heading information – replacing compasses now that
the poles are shifting
Weather Prediction
Skydiving – taking into account winds, plane and
dropzone location
Many more!
40. To understand the GPS surveying process, you need to understand what
GPS is. In short, GPS, or the global positioning system, is a satellite-
based navigation system. GPS was first developed for military use
starting in the 1970s and became fully operational in 1993. Since then, it
has expanded its use to consumer and commercial applications.
GPS uses a network of satellites, which communicate with receivers on
the ground. When a receiver requests data to calculate its location, four or
more GPS satellites will communicate with the receiver, sending the
position of the satellite, the time the data was transmitted and the distance
between the satellite and the receiver. The information collected from
these satellites then calculates the latitude, longitude and height of the
receiver. If the receiver is moving, continuous data collection can be used
to calculate the changing position of the receiver over time, which can be
used to calculate speed. No matter the weather conditions or time, GPS
can triangulate the signal and provide a location.
41.
42.
43. SEGMENTS OF GPS
1. Space Segment
The GPS constellation consists of 24 satellites arranged in 6
orbital planes of 55- degree inclination, 20,051 kilometers
(12,532 miles) above the Earth. Each satellite completes one
orbit in one-half of a sidereal day and, therefore, passes over the
same location on earth once every sidereal day, approximately
23 hours and 56 minutes. With this orbital configuration and
number of satellites, a user at any location on Earth will have at
least four satellites in view 24 hours per day
44. 2. Operational Control Segment
The GPS OCS consists of the master control station (MCS),
located at Falcon Air Force Base in Colorado Springs, Colorado;
remote monitoring stations, located in Hawaii, Diego Garcia,
Ascension Island, and Kwajalein; and uplink antennas, located
at three of the four remote monitor stations and at the MCS. The
four remote monitor stations contribute to satellite control by
tracking each GPS satellite in orbit, monitoring its navigational
signal, and relaying this information to the MCS. The four stations
can track and monitor the whereabouts of each GPS satellite 20
to 21 hours per day. Land-based and space-based
communications connect the remote monitoring stations with the
MCS.
45. 3. User Equipment
GPS user equipment varies widely in cost and complexity, depending on the
receiver design and application. Receiver sets, which currently vary in price
from approximately $135 or less to $30,000, can range from fairly simple
devices that provide only basic positioning information to complex
multichannel units that track all satellites in view and perform a variety of
functions.
Most GPS receivers consist of three basic components:
(1) an antenna, which receives the signal and, in some cases, has anti-
jamming capabilities;
(2) a receiver-processor unit, which converts the radio signal to a useable
navigation solution; and
(3) a control/display unit, which displays the positioning information and
provides an interface for receiver control.