Main Developments

Within the framework of the performance of a number of the projects in cooperation with MAO NAS of Ukraine and other organizations of Ukraine there were carried out the development and testing of new domestic technologies of centimeter accuracy positioning which comply with up-to-date concepts of developing the differential network GPS/GNSS subsystems (FKP/VRS/MAX-type) for rendering the information services of geodetic surveying and its different applications on the basis of centralized processing of stations and user observations. In 2007-2010 it was developed and tested the prototype of multifunctional information and measuring system (IMS) in Kiev, Chernigov and Cherkassy regions. IMS realizes the network (areal) differential correction of observation errors, rendering the information services and provides high precision user positioning in modes of automated post processing and real time (RTK) in the territory of the serviced region.

It has been created and currently developed the prototype of multifunctional mathematical and software complex (SW) «OCTAVA» for GNSS observations processing for the purpose of realizing of a number of functions. The main functions are: quality control and quality assurance of observations and ephemeris-and-temporal information of GNSS satellites, recovery of carrier-phase observations continuity, editing and analysis of preliminary data processing results, carrier-phase ambiguity resolution, modelling and correction of tropospheric and ionospheric errors and carrying out high precision positioning. More detailed about SW «OCTAVA» you may learn in section «SDK OCTAVA».

It is carried out a cycle of researches on estimation of the ionospheric delays spatial and temporal features (their single and double differences) with the purpose of determination of opportunities of using single-frequency GNSS equipment for centimeter accuracy positioning on middle baselines up to ~100 km.

It is developed the algorithmic and software toolset of estimation of the current integral zenith tropospheric delays (ZTD) with centimeter accuracy level by use of carrier-phase GNSS measurements of the network of permanent reference stations. In their turn, ZTD estimations are used for their interpolation (in conditions when it is possible and expedient) to the current GNSS user position with the purpose of positioning accuracy increase.

In 2010-2012 there was developed and verified a new effective technology and the appropriate program modules of static and kinematic centimeter accuracy positioning by dual-frequency GPS observations. One of the main peculiarities of this technology is achievement of high reliability (90-100%) of carrier-phase ambiguity resolution in conditions of short samples of kinematic observations (15-60 sec) on long baselines (up to ~100 km) in OTF mode (On-The-Fly, i.e. without static initialization). The characteristics of the developed technology of dual-frequency differential positioning are adequate to the characteristics of the well-known foreign software of the similar purpose.

It is developed the alternative strategy of the network processing of code and carrier-phase single-frequency GPS observations for centimeter level positioning in post-processing mode in conditions of sparse networks of dual-frequency GNSS stations. During the processing there are formed and used areal ionospheric and tropospheric corrections on the basis of observations of not only reference stations but also the observations of users themselves. This technology including a number of innovations has no analogs for the present moment.

In 2010-2011 the group together with the colleagues from MAO NAS of Ukraine took part in the performance of the project of Framework European Program FP7 «EEGS - EGNOS Extension to Eastern Europe», grant № 247698. In 2012-2013 the members of the group (according to the tasks of KhNURE and MAO NAS of Ukraine) have also participated in carrying out the works of the subsequent project «EEGS2 - EGNOS Extension to Eastern Europe: Applications», grant № 287179.

The number of perspective developments being performed at present includes the directions on creation of technologies of high precision positioning at long baselines (~1000 km and more) and determination of parameters of Low Earth Orbit Satellite (LEOS) motion with centimeter accuracy. Besides, it is planned solving the task of РРР (Precise Point Positioning) technology realization.