Nowadays (August 2017) position data can be obtained generally from satellite navigation systems (SNS), such as GPS and GLONASS, and satellite based augmentation systems (SBAS) which can be either global, such as EGNOS, GAGAN, MSAS and WAAS, or regional, such as NAVIC (IRNSS) in India. Two new global SNSs, Galileo and BeiDou, three new global SBASs, SDCM, KASS and SNAS, and one new regional SBA, QZSS in Japan, are under construction. The generic name given to all these abovementioned systems is GNSS (Global Navigation Satellite Systems). This paper presents details of the following: changes that have occurred in the cumulative core revenue in different GNSS market segments (road, Location Based Service LBS, surveying, agriculture, timing & synchronization, aviation, maritime, drones and rail in 2017) in the last 8 years; an overview of the GNSS industry and location-based services in the world; details of current and future GNSS market evolution; GNSS unit shipments in 13 different categories of maritime application; the frequency and constellation capabilities of GNSS receivers; GNSS frequencies that will be common in the future; the adoption of multi-constellation, multi-frequency and dual-frequency as key enablers of improved accuracy and integrity; GNSS services available for civil and authorized users, and multiple signals in the case of all four global SNSs.

Information about user’s position can be obtained from specialized electronic position-fixing systems, in particular, Satellite Navigation Systems (SNS) as GPS and GLONASS, and Satellite Based Augmentation Systems (SBAS) as EGNOS, WAAS, MSAS. All these systems are known also as GNSS (Global Satellite Navigation System). As the number of GPS and GLONASS satellites visible by the user is sometimes in restricted area not sufficient, and these SNS cannot provide information about integrity, there is one service for civil users only etc., new systems, global as well as regional, must be constructed. The last years gave a rise to many important changes in the operational status and practical exploitation of all these systems. New SNS as Galileo in Europe and Compass (Beidou) in China, new SBAS as GAGAN in India and SDCM in Russia, new regional SNS as IRNSS in India and QZSS in Japan are actually under construction. Additionally the new satellite blocks as GPS IIF and III, and GLONASS K1 and K2, the new signals as GPS L5 and L1C, and GLONASS LC3OC and L1OC, the new services and possible applications of the future system Galileo are presented in this paper

There are different scales related to time actually two the most important timescales are the TAI (Time Atomic International) and the UTC (Universal Time Coordinated). In addition to these times Satellite Navigation Systems (SNS) have developed their own system time: GPS Time (GPST), the GLONASS System Time (GLONASSST) and the Galileo System Time (GST). The sources, the generation and the relation between all these times and timescales are described in this paper. Additionally the time dilution of precision (TDOP) coefficient and the data concerning the time transmitted in navigation messages by satellites of different SNS will be presente

Satellite Navigation Systems (SNSs), the GPS system in particular, were available to civilian users from the beginning. The first community interested was the maritime one, for both professional and recreational purposes. Marine navigation distinguishes between five major phases, among those the port approach and operation in restricted waters and the marine navigation in the port. SNSs, today the GPS system and its differential mode DGPS, and Satellite Based Augmentation Systems (SBAS) as EGNOS and WAAS, provide a wide range of applications in both these phases, e.g. coupling SNS receivers with dedicated sensors installed on the ship’s bridge, e.g. AIS, aid in the berthing and docking of large vessels, by means of the position and the heading reference systems. In maritime restricted area, the SNS position accuracy can be decreased when the masking elevation angle causing by the obstacles is for the user on the ship greater than masking angle of observer’s receiver. This diminution depends on among other things the ship course, observer’s latitude, the height of the obstacle, the distance between the observer and the obstacle, here coast side. Additionally, the problem of availability of the integrity information to users and performances, and future use of the GLONASS system after modernization, Galileo and Compass systems actually under construction, new SBASs, the next DGPS and DGLONASS reference stations, and Eurofix with differential corrections to GPS including integrity messages in coastal navigation are described in the paper

Nowadays (October 2013) information about ship’s position is obtained generally from specialized electronic positioning systems, in particular, at present functionally satellite navigation systems (SNS) as GPS and GLONASS, and satellite based augmentation systems (SBAS) as EGNOS, WAAS and MSAS. Two next SNS, Galileo and BeiDou, and two next SBAS, GAGAN and SDCM, are under construction. After all the user of these systems, the maritime user also, continually meets and will meet with numerous different limitations of SNS coverage in restricted area, SBAS and DGPS reference stations coverage area, the lack of integrity information about the systems, and of many charts referred to WGS–84 datum, with problem of position fix in restricted area, etc

Currently (July 2014) an uninterrupted information about the ship’s position can be obtained from specialized electronic position-fixing systems, in particular, Satellite Navigation Systems (SNSs) as GSP and GLONASS and Satellite Based Augmentation Systems (SBASs) as EGNOS or WAAS. On each ship’s bridge one GPS stationary receiver is installed at least but on many ships there are two or even more GPS receivers. Nowadays, several hundred different end-user products and broad/chipset/modules are available on the world market, however for ship’s bridge several dozen models provided by a dozen or so manufacturers are designed only. In this paper 309 GPS receivers, 47 different models of 12 manufacturers installed on 188 ships of different types and with different lengths were taken into account. The relations between the type and the length of the ship, the number of the GPS receivers installed on one ship, the manufacturers and the models the most frequently used are presented.

The distributions (in per cent) of VDOP coefficient values for GPS nominal (27 satellites) and present (27,28 and 29 satellites) constellations are demonstrated. Different masking elevation angels for different observer's latitudes are considered. The GPS position and vertical accuracy in the "3D" mode and the position accuracy in the "2D" mode for different receivers and for different receiver's antenna heights are presented as well.

To date, a ship’s position can generally be obtained from functional satellite navigation systems (SNS), such as Global Position Systems (GPS and GLONASS), and Satellite-Based Augmentation Systems (SBAS), such as (European Geostationary Navigation Overlay Service (EGNOS), GPS-Aided Geo Augmented Navigation system (GAGAN), MTSAT Satellite Augmentation System (MSAS) and Wide Area Augmentation System (WAAS). Sometimes these systems are collectively called Global Navigation Satellite Systems (GNSS). Two more SNS, Galileo and BeiDou, one more SBAS, System for Differential Corrections and Monitoring (SDCM), and new regional systems, such as Quasi-Zenith Satellite System (QZSS) in Japan and Indian Regional Navigation Satellite System (IRNSS) in India, are also under construction. Information about all of these 11 systems is available on the internet. The number of links and the type of the information obtained from two search engines, Google and Bing, for the different keywords concerning each system are shown in the paper. Additionally, the analysis of the character and usefulness of the information placed on the pages of governmental organizations and institutions administering the above-mentioned systems, manufacturers of the satellites, receivers and different kinds of the institutional users is also provided.

Currently (April 2016) uninterrupted information about a ship’s position can be obtained from specialized elec- tronic position-fixing systems, in particular, Satellite Navigation Systems (SNSs) such as GPS and GLONASS and Satellite Based Augmentation Systems (SBASs) such as EGNOS or WAAS. The generic name given to all the above mentioned systems is Global Navigation Satellite Systems (GNSS). Many models, designed for the ship’s bridge and provided by about a dozen manufacturers, are available on the world market. In Europe, one of the most comprehensive sources of knowledge on the global GNSS market is a report published, on average, every 15 months by the European GNSS Agency GSA. Another receiver survey is published each year in the January number of the magazine “GPS World”. The detailed analysis of market report and receiver survey, possible use of EGNOS and Galileo in the maritime market, and different maritime applications of GNSS equipment are described in this paper.