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We present an innovative, small footprint, Low Frequency (LF) Terrestrial Positioning System (TPS) based upon Enhanced Loran (eLoran) that is cost-effective, easily transportable, and rapidly-deployable. We show that our proposed TPS is significantly smaller and more economical than previous generations. The technology underlying the system is stat...
Citations
... The LF electromagnetic waves have lower attenuations and therefore the Loran system can cover larger regions [1][2][3][4]. Among various kinds of antennas such as ferrite rod antennas [5], loop antennas [6,7], horn antennas [8], helical antennas [9], microstrip antennas [10], and finally monopole and dipole antennas [11][12][13][14][15][16][17][18][19][20][21][22][23], the best candidate for this frequency band as a transmitter antenna are monopoles or dipoles with some modifications due to their vertically polarized omnidirectional pattern and the capability of high power transmission. ...
... In the third section, the effects of supporting masts on the radiation resistance are shown for three kinds of Loran transmitter antennas with four masts. The first one is the sectional Loran transmitter (SLT) antenna [20], the second is the inverted cone antenna [21] and the third is the modified SLT antenna [22,23] which is named square top loaded (STL) antenna. Some illustrations and simulations of this paper use NEC [24]. ...
... The wires are of course isolated from the mast, at more than one point, since the coupling effect is important for this antenna. For example if the wires are isolated at each 40 m distances, the radiation resistance decreases about 0.75 Ω while if they are isolated from the mast to ground on the distances6,9,12,15,18,21,24, 27 and 40 (all in meters) the radiation resistance decreases about 0.25 Ω. The form of the wire supports are shown inFig. ...
Smartphones have become an essential rather than an optional gadget. With Smartphones, we carry with us a hand held computer with details about our social life, family members, transaction details and much more. Smartphones serve as a communication tool used to send messages, place and receive calls, surf the internet and play wide range of games. In this paper, we present a framework that helps us to track and pin-point the current location of the mobile and save the call logs, sent to our Web-based application. This framework couples GPS-based information with Google maps data and accurately determines the postal address of the lost mobile. The framework makes it possible to track the mobile location after specified regular intervals.
Radio systems for long-range navigation comprise a subclass of radio-navigation systems based on geodetically referenced and synchronized chains of terrestrial transmitting stations that provide accurate navigation at distances far from those stations. In fact, their development was an attempt to solve the problem of how to minimize the number of terrestrial transmitting stations needed to encompass the global operational area. The chapter aims at representing the very low frequency (VLF) and low frequency (LF) long-range navigation systems including their principles of operation, accuracy, coverage, budget of errors, interfering signals, signal processing techniques, and sensor architecture. These subjects are augmented by including various system modernization aspects and their integration with satellite RNS. The Integrated Solution utilizes both GNSS and all-Loran data to estimate additional secondary factor (ASF) corrections. The chapter provides all Loran-only and GNSS-only solutions to show how the GNSS or all Loran data contributes to the combined solutions.
The traditional view is that different types of interference (or the same type interference generated in different ways) have no effect on the anti-interference performance of GNSS adaptive antenna array. However, in the actual course of the study, it is found that the interference suppression performance of the adaptive array antenna differs for different types of interference. The difference is not obvious when the interference intensity is at low level, but become relatively significant when the interference power becomes larger. There are two types of typical wideband interference in GNSS system: matching spectrum wideband interference and White Gaussian Noise (WGN) wideband interference. In array receiver simulations, the array signal generation methods of these two kinds of interference are different, which was analyzed elaborately in this paper. Signal to aliasing noise ratio (SNRa) of the two types of typical wideband interference was analyzed. It was demonstrated in this paper that SNRa difference is the main reason that causes interference suppression performance difference of two kinds of interference in the same array receiver. Simulation of array transfer function of wideband model verified the theoretical analysis.
The main objective of Global positioning system (GPS) is to determine our position on earth in three dimensions: east-west, north- south, and vertical in terms of longitude, latitude and altitude. The GPS navigation system presented in this paper provides very useful information about present geographical information which includes latitude, longitude, altitude, current velocity and Greenwich meridian time reference. It is capable of indicating active and inactive PRN number (pseudo random code) of satellites used for GPS tracking in terms of visual plane positioning indicator system. A study of comparison of present and previous geographical location is also available in this system. The system helps in determining signal to noise ratio in decibels of various PRN satellites which is used for determining signal strength of GPS signals for studying Ionospheric scintillation effects on GPS signals. It also gives visual representation of various National Marine Electronics Association (NMEA) GPS strings which gives navigational, satellite orbital and clock information.
The use of the Global Positioning System (GPS) in everyday life is pervasive and its use increasing, especially as additional multi-constellation Global Navigation Satellite Systems (GNSS), i.e. Galileo, Compass, and GLONASS, and Regional Navigation Satellite Systems (RNSS) become fully operational and “fill the world's skies.” In many applications, its use is essential even when the user doesn't know that it is being used (e.g., cell phone service).
