Satellite-based localization using the global positioning systems (GPS) has attracted ever growing attention in the last few years. In this work, we present a signal processing technique for initial code acquisition and synchronization of a GPS signal, such as the one used by position location techniques in 3G wireless scenarios. Several computer simulations have been accomplished to validate t...

The aim of this paper is to consider the problem of node localization for geographical routing protocols in ad hoc networks. We propose a distributed positioning algorithm that does not rely only on GPS-like systems (Global Positioning System). Instead, it is assumed that just a part of the nodes belonging to that network is GPS-compliant. Therefore in this paper it is proposed to give position...

Advances in alternative fuel technologies and increasing motor vehicle fuel efficiency may result in a decline or flattening of demand for conventional fuels in the U.S. in the coming decades. One outcome of this development maybe a reduction in state and federal income from motor fuel taxes, the primary source of funding to maintain and improve the transportation infrastructure. To keep pace w...

The US Global Positioning System (GPS) and the USSR (and later Russian) system Glonass have existed for decades. Europe is developing Galileo and China launched Beidou which was the first Regional Navigation Satellite System (RNSS) and then announced Compass, a Global Navigation Satellite System (GNSS). Japan is planning its own regional augmentation to GPS and Galileo known as the Quasi-Zenith...

The global positioning system (GPS) provides accurate positioning and timing information useful in many applications. An adaptive lattice predictor for the anti-jamming purpose will be proposed. The adaptive filter is applied here to accurately predict the narrowband waveform based on an effective and computationally efficient stochastic-gradient algorithm. Simulation results show that our prop...

I.inc-of-sight ionosphere measurements derived from differcncing dual-frequency Global Positioning System (GPS) range data are corrupted by instrumental biases in both the receiver and GPS satellite transmitters due to hardware delays in the L1 and L2 signal paths, The lineof-sight differential delay can be modeled as the sum of a rccciver bias, a satellite transmitter bias, and the line-ofsigh...

Most integrated inertial navigation systems (INS) and global positioning systems (GPS) have been implemented using the Kalman filtering technique with its drawbacks related to the need for predefined INS error model and observability of at least four satellites. Most recently, a method using a hybrid-adaptive network based fuzzy inference system (ANFIS) has been proposed which is trained during...

We present the results of C/A code common-view Global Positioning System (GPS) comparisons between the UTC (NIST) time scale, located at the National Institute of Standards and Technology (NIST) in Boulder, Colorado, and the Brazilian national time scale, UTC(ONRJ), located at the National Observatory (ONRJ) in Rio de Janeiro, Brazil. The two time scales are separated by a long baseline of ~860...

Several spaceborne altimeters have been built and flown, and others are being developed, to provide measurements of ocean and ice sheet topography. Until the launch of TOPEX, altimeters were single frequency systems incapable of removing the effects of ionospheric delay on the radar pulse. With the current state of the art in satellite altimetry, the ionosphere causes the largest single error w...

The US Global Positioning System (GPS) is currently the primary source of Position, Navigation and Timing (PNT) information in maritime applications, whether stand-alone or augmented with additional systems. This situation will continue in the future with GPS, possibly together with other Global Navigation Satellite Systems (GNSS) e.g. Galileo, being the core PNT technology for e-Navigation – t...