History

Using a marine differential subsystem of the SNA in order to improve their accuracy characteristics in accordance with the IMO Resolutions, in particular, A.815 (19) is made mandatory for the navigation of ships in order to ensure the safety of navigation on the approaches to ports in the narrows and in areas with limited freedom of maneuver.

The feasibility of network deployment control of corrective marine differential subsystem stations, GLONASS / GPS is determined by the need to establish a reliable navigation aid safe navigation of vessels, their efficient operation and to prevent environmental disasters with heavy shipping, in the approaches to ports, in the port waters and the narrows, where freedom to maneuver is limited.

Network control and correction station is basic technical means to ensure high-precision coordinate-time information about the location of ships in coastal waters.
It is organized in the regions where the intensity of traffic and the existing navigational and hydrographic support to required improving safe navigation of vessels in order to protect the environment, as well as reducing delays and achieving rhythmic traffic vessels of the fleet.

Control and correction stations of the maritime differential subsystem of GLONASS /GPS

The receiving station can receive signals from all of navigational satellites, GLONASS / GPS, in the zone of radio visibility of the antenna. Then, using the known exact coordinates of the location of the receiving antenna base station generates and transmits to the radio beacon differential corrections to the pseudorange measurements on each satellite in the form of standard messages in a format RTCM SC-104. In addition, in the operative reports included information about possible violations in the operation of hardware subsystems and satellite differential GLONASS, GPS. The amendment is formed by GNSS receiving station and is transmitted by beacon. Beacon is broadcasted timely information in the form of the correction signal DGLONASS DGPS. Marine navigation receivers, taking both SNS GLONASS signals, GPS and beacon signals containing differential corrections, determine the location of the vessel with an error not exceeding several meters.

Block diagram station control and correction of differential subsystem GLONASS / GPS

GNSS reference station CH-3501 receives signals GLONASS and GPS, makes the data correction and transmits messages in the radio beacon.

The DGNSS station of integral control СН-3502 is received signals of GLONASS and GPS satellites, as well as the data correction from beacon. She is check of data within acceptable limits.

CH-3502 is constantly transfer the reference station the results of monitoring the functioning of the operating system and data correction. The alarm is generated when the correction is more then tolerance limits an. The alarm is the most important when generated by a deviations of coordinates that is when deviations over the allowable limit.

Works businesses in this area

The works to create a hardware stations of control and correction were launched in 1999.

So far, developed and transferred to the production equipments of stations control and correction CH-3500, CH-3500MK, CH-3500MKA.

For the organization mode of local differential correction outside the marine stations of control and corrections was developed a set of serial production equipment in the local hardware diferential subsistem CH - 3022, CH - 3002 and a set of radio modems. CH - 3022 - device for making differential corrections GLONASS \ GPS - Base Station, CH - 3002 - GLONASS \ GPS navigation receiver - the mobile station.

With this kit are achieved accuracy of the coordinates within 2 - 5 m at a distance of 10 - 20 km from the place of installation of the base station - CH-3022.

The using projects of stations control and correction

The first set of stations equipment was installed in 2000 in Novorossiysk, Russia.

In October, 2001 SE «Orizon-Navigation», in collaboration with teams of Kerch seaport and hydrography of Ukraine, was put into operation first in Ukraine station of control and correction marine differential subsystem GLONASS / GPS CH-3500.

The station of control and correction CH-3500 is designed SE «Orizon-Navigation», in close collaboration with the design bureau of navigation systems «KB Navis» (Russian Federation). The strategic partnership between two leading companies in the CIS in the field of satellite navigation equipment has created, which is clear advantages:

• work on two systems GLONASS / GPS;
• relatively low cost;

and eventually

• providing information and technological independence of Ukraine.

The stations of control and correction CH-3500 certified in Russia and has a «certificate of type approval of equipment DGNSS MCC 4/3-1338-2001C on 01/06/01».