Throughout the last decade, a trend towards the development of software-based Global Navigation Satellite System (GNSS) receivers has evolved in the fields of scientific research. Software-based GNSS receivers feature a high flexibility for the adaptation to several applications, serve as a development platform for studying new algorithms and techniques, and especially have the advantage of req...

With the recent rapid revival of the GLONASS constellation, it is possible for the GLONASS system to provide Full Operational Capability (FOC) service before the end of 2011. CDMA signals are now additionally modulated onto the first GLONASS-K satellite which was launched on February 26, 2011. It is envisaged that GNSS users will benefit from more visible satellites, better precision and higher...

Radio interference is one of the major concerns in using the global positioning system (GPS) for civilian and military applications. Interference signals are produced not only through all electronic systems but also illegal jammers. Among different types of interferences, continuous wave (CW) interference has strong adverse impacts on the quality of the received signal. In this paper, we make m...

In general handheld GPS receivers are used for absolute positioning or for relative positioning using DGPS-services or WAAS/EGNOS signals. The positioning is realized using code pseudo-ranges. Moreover it is well known that some of the handheld receivers use phase-smoothed code for positioning. This means that the phase signal is available and may be used for Precise Differential GPS (PDGPS) po...

Carrier-phase smoothing code (CPSC) is a code-smoothing technology that uses carrier-phase changes to reduce noise in Global Navigation Satellite System (GNSS) appliances. Although CPSC performs well reducing and easy implement, it trade-off between the reduction of increase variation ionospheric errors. The width window needs be large noise. However, wider increases To circumvent this dilemma,...

different methods exists for jamming mitigation and we should choose a method based an the jammer type and other parameters. one of the jammers is narrow band fm jammer and we use subspace projection techniques for the suppression of this type of jammer. in subspace projection technique, we estimate the if of signals and construct the subspace vector that is orthogonal to jammer vector by incre...

Due to their weak received signal power, Global Positioning System (GPS) signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers w...