13-19 March 2016
Africa/Johannesburg timezone
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Displaying 123 contributions out of 123
Type: Oral Presentation Session: Conference Dinner
Track: 5: Geodetic and Astrometric VLBI Results
Through the analysis of geodetic VLBI data a multitude of scientific topics in geodesy, geophysics, and astronomy can be covered. Starting from astrometry, relativity, and the essential contribution of VLBI to the terrestrial reference frames, geophysical effects like loading and deformation of the Earth’s crust, variations of the Earth orientation parameters, and changes of the troposphere and ... More
Presented by Prof. Harald SCHUH on 16 Mar 2016 at 16:50
Type: Poster Presentation Session: Poster4-6
Track: 6: VLBI Observations of Space Vehicles
On Sept. 20, 2015, the Chinese CZ-6 test rocket was launched successfully from TaiYuan Satellite Launch Center, and 20 satellites was sent simultaneously into a circular, near-polar and 520 Km altitude orbit. Among these 20 satellites, four CubSats, named with APOD (Atmospheric density detection and Precise Orbit Determination), are projected for atmospheric density in-situ detection and derivati ... More
Presented by Dr. Guangli WANG on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
The combination of space geodetic solutions is critically reliant on the availability of local tie vectors, which are the relative positions of the reference points of co-located space geodetic instruments determined by some survey technique. Tie vectors enter the combination of space geodetic solutions effectively as a fifth technique and are not only necessary for rigorous terrestrial reference ... More
Presented by Sten BERGSTRAND on 15 Mar 2016 at 11:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
We are developing a new broadband VLBI system, named GALA-V with aim of frequency comparison between atomic time standards over intercontinental distances. The development of broadband GALA-V system is coordinated to be as compatible as possible with the VGOS system. Kashima 34m antenna that had modified Cassegrain optics was enabled to carry out broadband observation with originally developed two ... More
Presented by Dr. Mamoru SEKIDO on 14 Mar 2016 at 09:40
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
Satellite Laser Ranging (SLR) is used to measure accurately the distance from ground stations to retro-reflectors on satellites and on the Moon. SLR is one of the fundamental space geodetic techniques that define the International Terrestrial Reference Frame (ITRF), which is the basis upon which many aspects of global change over space, time, and evolving technology are measured; with VLBI the two ... More
Presented by Dr. Graham APPLEBY on 14 Mar 2016 at 09:15
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
Now that significant amounts of data have begun to flow through the VGOS pipeline, we are encountering real-world issues in the fringe-fitting process. In order to create a high-quality geodetic observable one wants to minimize the sensitivity of group delay to instrumental parameters that may change over time, while at the same time maximizing the amount of information that is extracted. This tal ... More
Presented by Dr. Roger CAPPALLO on 14 Mar 2016 at 14:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Generating the contribution of the International VLBI Service for Geodesy and Astrometry (IVS) to the ITRF2014 was the main task of the IVS Combination Center at the Federal Agency for Cartography and Geodesy (BKG, Germany) in 2015. Starting with the ITRF2005, the IVS contribution to the ITRF is an intra-technique combined solution using multiple individual contributions from different institution ... More
Presented by Sabine BACHMANN on 16 Mar 2016 at 12:25
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The ICRF3, the next realization of the International Celestial Reference Frame, is going to be built within the next two years for approval at the IAU 2018 General Assembly. This timescale is driven by the forthcoming optical reference frame to be built by the Gaia mission and aligned at best with the ICRF3. The ICRF3 work is carried out by an IAU Working Group set up in 2012. While the work so fa ... More
Presented by Dr. Patrick CHARLOT on 16 Mar 2016 at 15:00
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
As chair of the Technical and Operations Group (TOG) of the European VLBI Network (EVN) I would like to present an overview of the technical aspects of the EVN. I will explain which institutes and telescopes constitute the EVN, and their main characteristics and observation frequencies. The scheduling process together with fringe tests, network monitor experiments, standard observations, e-VLBI ob ... More
Presented by Dr. Pablo DE VICENTE on 16 Mar 2016 at 09:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Usually celestial radio sources in the celestial reference frame (CRF) catalog are divided in three categories: defining, special handling, and others. The defining sources are those used for the datum realization of the celestial reference frame, i.e. they are included in the No-Net-Rotation (NNR) constraints to maintain the axis orientation of the CRF, and are modeled with one set of totally con ... More
Presented by Dr. Maria KARBON on 17 Mar 2016 at 10:30
Type: Oral Presentation Session: Oral6: VLBI observations of Space Vehicles
Track: 6: VLBI Observations of Space Vehicles
VLBI is a radio astronomy tool with very high space angle resolution and Chinese VLBI Network has played a important roles in the Chang’E series lunar mission. In the upcoming Chinese lunar and deep space missions, higher angular position ability is needed. For these reasons, we carried out research on accurate spacecraft positioning and conducted several space vehicles phase-referencing positio ... More
Presented by Mr. Weimin ZHENG on 17 Mar 2016 at 16:30
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
The Sejong station is a part of SGOC(Space Geodetic Observation Center) which belongs to NGII(National Geographic Information Institute). We will present conventional S/X system issues that we need to improve, establishment of sever cluster for S/W correlation(Storage about 100TB), local tying results for collocation, installation of the ARGO(Mobile SLR system, 40cm diameter) which developed by KA ... More
Presented by Mr. Sang Oh YI on 15 Mar 2016 at 11:40
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
On its way through the atmosphere, the signals of space-geodetic techniques, such as GNSS or VLBI, are delayed and affected by bending and attenuation effects relative to a theoretical path in vacuum. Changing atmospheric conditions contribute considerably to the error budget of the observations. At the same time, space-geodetic techniques play a crucial role in the understanding of the Earth's at ... More
Presented by Mr. Sebastian HALSIG on 17 Mar 2016 at 12:15
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
BACC(Beijing Aerospace Control Center), as the command center for the Chinese space program, got access to VieVS in 2011. Since 2013, IVS VLBI data has been downloaded and analyzed automatically with VieVS at BACC and the geodetic products will be provided firstly in the presentation. VieVS was also used to estimate the coordinates of new Chinese VLBI telescopes with domestic VLBI network in the p ... More
Presented by Johannes BOEHM on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
The VLBI Intensive sessions are one-hour long, usually single-baseline VLBI sessions performed every day in order to estimate UT1-UTC. Due to the small number of observations in these sessions, the latency between observation and results is relatively short, normally a few days. However, the accuracy of the UT1-UTC estimates is significantly lower than expected based on their formal errors. Althou ... More
Presented by Dr. Tobias NILSSON on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Terrestrial reference frames (TRF) of high quality are indispensable for many geoscientific and geodetic applications including very long baseline interferometry (VLBI) data analysis. While secular station coordinate changes, e.g. due to tectonic plate motion, can be well represented by a linear model, current accuracy requirements also demand modeling of non-linear signals such as surface deforma ... More
Presented by Mr. Benedikt SOJA on 16 Mar 2016 at 14:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The Second Realization of the International Celestial Reference Frame (ICRF) used dual-frequency VLBI data acquired for geodetic and astrometric purposes from 1979-2009 by organizations coordinated by the IVS and various precursor networks. Since 2009 the data set has been significantly broadened, especially by observations in the Southern Hemisphere, and modeling of astronomical, geophysical and ... More
Presented by Dr. Chopo MA on 16 Mar 2016 at 15:25
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
Relativistic geodesy is typically seen as a new type of gravity potential measurement technique using very high accuracy clocks; these clocks are more stable (by a factor of 100 or 1000) than the hydrogen masers currently used at VLBI stations. In modern terms however, geodesy entails much more than just geodesy of the Earth, therefore the term relativistic geodesy is re-assessed. The possible con ... More
Presented by Prof. Ludwig COMBRINCK on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
We have used GPS-based local-tie measurements simultaneously with geo VLBI observations since 2008 during every geodetic VLBI session at Metsähovi. This system uses gimbal-mounted GNSS-antennas that are mounted on the reflector of the Metsähovi 14 m radio telescope. A similar system has been installed in 2013 at the Onsala 20 m radio telescope and been used for a large number of VLBI sessions, i ... More
Presented by Sten BERGSTRAND on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
Multi-band concurrent observation capability for the frequencies bands commonly used in EVN greatly could improve the VLBI scientific opportunities, even enabling important simplification in the radiotelescope operations. The project for a 1.5 - 15.5 GHz fully digital receiver is presented with the possible solutions for a smooth introduction in the different from each other EVN radiotelescope ... More
Presented by Dr. Gino TUCCARI on 14 Mar 2016 at 10:20
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The existing 20 m telescope in Ny-Ålesund was set in operation in 1994. The telescope is more than 20 years now and is ready for retirement. We decided to build a VGOS core site with twin telescopes. The existing telescope is just 70 meters away from the runway and the CAA did not allow us to build anything more so close. The new site is about 1500 meters northwest of the old telescope and we ... More
Presented by Mr. Leif Morten TANGEN on 14 Mar 2016 at 11:15
Type: Oral Presentation
Presented by Axel NOTHNAGEL on 17 Mar 2016 at 16:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Unlike CONT11, CONT14 does not have official information on common frequency standards for co-location sites. Nevertheless, according to Kwak et al. (2015), we have a possibility to find the co-located sites, which used the same clocks, through comparing clock rates from single technique solutions. Moreover, CONT14 includes co-located VLBI radio telescopes, i.e. HOBART26 and HOBART12. Therefore, i ... More
Presented by Dr. Younghee KWAK on 16 Mar 2016 at 14:45
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
K-band (22 GHz) radio observations have the potential to form the basis for the most accurate celestial reference frame ever constructed. Relative to the standard S/X (2.3/8.4 GHz) observing bands, K-band is expected to exhibit a reduction in extended source morphology and core-shift. This reduction in astrophysical systematics should allow for a more stable celestial reference frame at K-band and ... More
Presented by Dr. Aletha DE WITT on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster4-6
Track: 6: VLBI Observations of Space Vehicles
Using the same frequency standard, a high-precision phase delay can be obtained in a connected element interferometry (CEI) system. Beidou GEO navigation satellite C02 is tracked from a CEI observations, where the CEI of the two stations at hangtiancheng and shahe linked by a phase stabilization system is built by Beijing Aerospace Control Center (BACC). And Beidou GEO navigation satellite C03 is ... More
Presented by Dr. Fengchun SHU on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral4: Data structures and Analysis Strategies in the VGOS Era
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
In a traditional least squares adjustment of parameters to the VLBI observation, typically tropospheric as well as clock parameters are determined in form of continuous piece-wise linear functions (CPWLF) with a given temporal resolution. As the VLBI observations are not equidistant, and on the contrary, exhibit gaps of sometimes several hours, singularities arise due to unresolvable parameters in ... More
Presented by Dr. Thomas ARTZ on 16 Mar 2016 at 11:10
Type: Poster Presentation Session: Poster1-3
Track: 1: Advances in VGOS Stations and Technology
The Geospatial Information Authority of Japan (GSI) is constructing a new VGOS station in Ishioka. The construction of the 13-m antenna has been finished, and a new operation building will be completed by February 2016. Ishioka 13-m antenna is observing legacy S/X-band VLBI observation with Tsukuba 32-m antenna by using tri-band feed system. We have also carried out some broadband experiments coll ... More
Presented by Mr. Ryoji KAWABATA on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
Shanghai Astronomical Observatory has upgraded its DiFX cluster to a 420 cpu cores and a 432 TB storage system at the end of 2014. An international network connection for the raw data transfer has also been established. The routine operations for IVS sessions including CRF, AOV, and APSG series began from the ealy 2015.Some X/Ka fringe search experiments were conducted with Tianma 65-m radio teles ... More
Presented by Dr. Wu JIANG on 16 Mar 2016 at 10:00
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
A first test implementation of an auxiliary data archive is tested at the Geodetic Observatory Wetttzell. It is software which follows-on the Wettzell SysMon, extending the database and data sensors with the functionalities of a professional monitoring environment, named Zabbix. Some extensions to the remote control server on the NASA Field System PC enable the inclusion of data from external ante ... More
Presented by Dr. Alexander NEIDHARDT on 15 Mar 2016 at 10:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The new VLBI observing system (OCTAVE-DAS) have been developed based on the VSI-H and VDIF specifications at NAOJ (National Astronomical Observatory of Japan). It consists of 1) a high speed 1-20 Gsps 3-10 bit RF direct ADC (OCTAD) enable us to acquire not only wide intermediate frequency but also radio frequency up to 50 GHz and have DBBC functions for VGOS (VLBI Global Observing System), 2) a co ... More
Presented by Dr. Tomoaki OYAMA on 14 Mar 2016 at 14:15
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
The beacon of CE-3 satellite have several tones for communication and VLBI tracking. In order to improve data transferring and processing efficiency, we tried the local-correlation method which was different from the one used in CE-3 project. The Time delay model used in local-correlation experiment also differed from normal time delay model. The result shows that there are a few dozen meters of d ... More
Presented by Yidan HUANG on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
In a previous study, we characterized radio sources observed by Very Long Baseline Interferometry by different criteria in both radio and optical domains (see the abstract "VLBI sources in optical and radio"). On the basis of the data derived from this study, we constructed several celestial reference frames by choosing a set of defining sources and studied their stability by two ways, statistica ... More
Presented by Mr. César GATTANO on 17 Mar 2016 at 10:00
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
Difxcalc is a version of calc11 modified specifically for the DiFX correlator. It is a replacement for the calc9.1 'calcserver' currently in use. To create difxcalc, all of the Mark3 database handler calls were removed from calc11 and new input, output and initialization modules were written and the flow of the program was modified for correlator usage. Difxcalc takes as its input the .calc ... More
Presented by Dr. David GORDON on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral6: VLBI observations of Space Vehicles
Track: 6: VLBI Observations of Space Vehicles
In recent years much effort has been undertaken to combine space geodetic observations on-board satellites, known as co-location in space. Whereas for SLR and GNSS, co-locations on-board satellites already exist (LEO, GNSS), no such satellites are allowing at present for VLBI observations. In order to cure this situation new satellite missions like GRASP are considered, new observation concepts li ... More
Presented by Prof. Markus ROTHACHER on 17 Mar 2016 at 15:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The Earth Orientation Parameters (EOP) are arguments of the time-dependent rotation matrices describing the difference in orientation between the Earth crust-fixed reference system, ITRS, and the space-fixed reference system, ICRS. Very Long Baseline Interferometry (VLBI) is the technique that connects the realizations of ITRS and ICRS in terms of orientation directly on the observation level. Man ... More
Presented by Dr. Robert HEINKELMANN on 17 Mar 2016 at 14:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Short term (daily to annual) variations in LOD are highly correlated with Atmospheric Angular Momentum. It has been known since the late 1980s and early 1990s that you could detect the effect of El Nino in the Length of Day (LOD). I review these results, paying particular attention to the current El Nino which is still developing, and is one of the strongest ever recorded. I look at correlation w ... More
Presented by Dr. John GIPSON on 17 Mar 2016 at 14:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
One of the primary goals of VLBI is the determination of a CRF. Currently the third realization of the internationally adopted CRF, the ICRF3, is under preparation. In this process, various optimizations are planned to realize a CRF which does not only benefit from the increased number of observations. For instance, various campaigns have been performed to sample the southern hemisphere with a bet ... More
Presented by Mr. Andreas IDDINK on 17 Mar 2016 at 09:30
Type: Poster Presentation Session: Poster1-3
Track: 1: Advances in VGOS Stations and Technology
A series of joint test observations using three 13-m VGOS antennas were carried on between September and November, 2015. These were include 256 Mbps experiments as well as first 2 Gbps observations. Different working setups of DBBC were tested at Yebes, data recorded, and transferred to IAA Correlator Center. Combined correlation of mixed bandwidth data from KVAZAR antennas and Yebes were performe ... More
Presented by Dr. Pablo DE VICENTE on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
The Geodetic Observatory Wettzell features a 20 m radiotelescope (RTW) as well as two new 13.2 m TWIN telescopes. Whilst RTW performs routine operations since 1984, the first of the TWIN telescopes, TTW1, has entered its productive phase in mid 2014, and TTW2 has just been equipped with an Elevenfeed broadband receiving system. The triple telescope array at Wettzell establishes a geodetic very ... More
Presented by Prof. Torben SCHüLER on 15 Mar 2016 at 11:25
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
A new release of the telescope control software e-RemoteCtrl, which is designed to run VLBI observations remotely, has been extended with new monitoring capabilities. The software extension is a test for further monitoring and control infrastructures for complete VLBI networks. The poster shows Ideas and already implemented elements.
Presented by Dr. Alexander NEIDHARDT on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster1-3
Track: 2: VGOS Strategies and Expected Results
The organization of first fast slewing observations with new VGOS antennas was decided during the VTC meeting at Ponta Delgada. The goal was to observe S/X-schedules regularly, using the fast slewing capabilities of the antennas as long as they are equipped with classic S/X-capabilities. The poster/presentation discusses and shows first results of these observations.
Presented by Dr. Alexander NEIDHARDT, Dr. Pablo DE VICENTE on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
Continuous VLBI Campaigns (CONT) started in 1994 with the goal of demonstrating state of the art VLBI over a continuous period of time. The first CONT was followed by campaigns in 1995 and 1996. After a six year hiatus, CONT campaigns were organized approximately every three years from 2002 through 2014. In this presentation we primarily focus on the cornerstones of each CONT campaign. Specificall ... More
Presented by Mrs. Cynthia THOMAS on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
Onsala Space Observatory hosts two 2.3 m radio telescopes called SALSA ("Such a lovely small antenna") which are utilised to bring front-line interactive astronomy to the classroom. Until now SALSA has been used for astronomical educational purposes solely, in particular demonstrating the concept of single dish measurements. However, it is possible to combine both SALSAs to an interferometer by ma ... More
Presented by Prof. Thomas HOBIGER on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
VLBI(Very Long Baseline Interferometry) is an important radio astronomy technology, is widely used in deep-space probers high-precision measurement. The correlator as the core data pre-processing equipment of VLBI, its performance is very important. At present, China VLBI data acquisition system (CDAS) can collect data 2Gbps, and multiband combination can reach 16Gbps or 32Gbps. For ensure the r ... More
Presented by Ms. Jiangying GAN on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster1-3
Track: 2: VGOS Strategies and Expected Results
A number of new VGOS-radio telescopes are built or under construction, partly at new locations. VGOS radio telescopes enable observations in the range of 2-14 GHz. For this reason VGOS radio telescopes are much more receptive for unwanted radio frequency interference. RFI originates from local transmitting devices as well as from space based transmitting systems. Some space-borne devices may cause ... More
Presented by Brian COREY, Dr. Vincenza TORNATORE on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The International Celestial Reference Frame (ICRF) are constructed using catalogs of extragalactic radio source (mainly quasars) positions measured at 2.3 and 8.4 GHz with the Very Long Baseline Interferometry (VLBI) technique. Most extragalactic radio sources exhibit spatially extended structures on milliarcsecond and sub-milliarcsecond scales which are variable in both time and frequency. These ... More
Presented by Mr. Sayan BASU on 17 Mar 2016 at 11:15
on 18 Mar 2016 at 09:00
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The International VLBI Service for Geodesy and Astrometry (IVS) Combination Center at the Federal Agency for Cartography and Geodesy (BKG, Germany) is responsible for generating combined Earth orientation parameter (EOP) products. Additionally, results of combined station coordinates and a terrestrial reference frame based on VLBI observations are generated. For providing information on the combi ... More
Presented by Sabine BACHMANN on 14 Mar 2016 at 17:00
on 19 Mar 2016 at 09:00
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The BKG (Federal Agency for Cartography and Geodesy) Data Center is one of the three IVS Primary Data Centers. It archives all VLBI related data of IVS components and provides public access for the community. The VLBI Analysis Group of BKG is part of the jointly operated IVS Analysis Center of BKG and the Institute for Geodesy and Geoinformation of the University of Bonn. The BKG is res ... More
Presented by Dieter ULLRICH on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
On October 7 and 8, 2015, the IVS Directing Board held an IVS Retreat at the Dominion Radio Astrophysical Observatory, Penticton, BC, Canada, to discuss current implications and future challenges of the IVS’s existence and operations. In order to benefit from outside views, six external advisors had been invited as well. The group spent two days discussing correlation, product lines, institution ... More
Presented by Axel NOTHNAGEL on 14 Mar 2016 at 10:05
on 13 Mar 2016 at 18:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The BeSSeL Survey (Bar and Spiral Structure Legacy Survey) is a VLBA Key Science project. The primary goal of the survey is to study the spiral structure and kinematics of the Milky Way, by measuring distances and proper motions to masers in regions of massive star formation across large portions of the Milky Way. To measure the distances of masers via trigonometric parallaxes, the relative positi ... More
Presented by Dr. Bo ZHANG on 17 Mar 2016 at 11:45
Type: Poster Presentation Session: Poster1-3
Track: 2: VGOS Strategies and Expected Results
In February 2014, the VGOS Project Executive Group (VPEG) presented the so-called VGOS Observing Plan, which outlined possible steps on how to go from initial VGOS broadband tests to intermediate observing scenarios to the fully operational VGOS system. The document introduced VGOS trial campaigns as the initial means to accustom the VGOS stations as well as the subsequent component types to the ... More
Presented by Dirk BEHREND on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
An on-going goal of the GSFC Analysis Center is the improvement of the UT1 formal error obtained from the IVS-INT01 sessions, as well as the improvement of related metrics, such as robustness against atmospheric turbulence. Improvement can be achieved by improving the scheduling and/or the analysis of these sessions. Here we report on our latest efforts to improve the performance of the IVS-INT01 ... More
Presented by Dr. John GIPSON on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The Kokee Park Geophysical Observatory's 12m is expected to see First Light early 2016.  A description of the integration and testing that was performed at MIT Haystack Observatory before shipping the signal chain is described.  This is followed by a summary of the teams work that had to occur before first light and the initial results. Beyond KPGO first light focuses on the commis ... More
Presented by Dr. Chet RUSZCZYK on 14 Mar 2016 at 12:00
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
The Metsähovi Geodetic Fundamental Station is a key infrastructure of the Finnish Geospatial Research Institute (FGI). It is a Global Geodetic Observing System (GGOS) core site, i.e., member of global network of geodetic stations which is used in maintaining global terrestrial and celestial reference frames, computing precise orbits of satellites, and for geophysical studies. Metsähovi is one of ... More
Presented by Dr. Nataliya ZUBKO on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral6: VLBI observations of Space Vehicles
Track: 6: VLBI Observations of Space Vehicles
Near-field VLBI is a radio astronomical technique that, when applied to observations of spacecraft, provides unique insights into those areas of a space mission's scientific programme requiring precise determination of the spacecraft's lateral position on the celestial sphere and its radial velocity. This technique was pioneered 30 years ago with the tracking of VEGA balloons to determine the win ... More
Presented by Dr. Bob CAMPBELL on 17 Mar 2016 at 15:30
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
We present the status of the Bonn Correlator Center (2015/2016) for astronomical and geodetic correlation. The correlator center is being operated jointly by the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn, the Federal Agency for Cartography and Geodesy (BKG) in Frankfurt with support from the Institute of Geodesy and Geoinformation (IGG) in Bonn for more than 20 years. We will ... More
Presented by Arno MUESKENS on 16 Mar 2016 at 09:30
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
IAA finished work on creation of new generation radio interferometer with two VGOS antennas at the Badary and Zelenchukskaya co-location stations. The series of 48 one base 1 hour VLBI sessions (up to four sessions per day) were performed from 04 Nov to 18 Nov 2015. Observations were carried out using wideband S/X receivers, 3 X-band and 1 S-band 512 MHz channels at one or two circular polarizatio ... More
Presented by Prof. Alexander IPATOV on 15 Mar 2016 at 10:15
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
We simulated future networks of VLBI+SLR sites to assess their performance. The objective is to build a global network of geographically well distributed collocated next generation sites from each of the space geodetic techniques. The network is being designed to meet the GGOS terrestrial reference frame goals of 1 mm in accuracy and 0.1 mm/yr in stability. We simulated the next generation network ... More
Presented by Dr. Dan MACMILLAN on 15 Mar 2016 at 09:00
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
With the transition to VGOS, co-located radio telescopes will be common at many sites. This can be as a sibling telescope, when a VGOS antenna is built next to a legacy one or as the concept of a twin telescope, with two identical VGOS antennas. The co-location of two antennas offers new possibilities in both operation and analysis. The immediate question for observing with a sibling/twin telesc ... More
Presented by Dr. Lucia PLANK on 15 Mar 2016 at 09:30
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Due to the highly volatile character of the neutral atmosphere, the modeling of the related propagation delay is challenging. This poses the most prominent limitation in the precision and accuracy of the parameters estimated in very long baseline interferometry (VLBI) data analysis. Hence, it is of paramount importance that all parameters involved in the process to describe the atmosphere induced ... More
Presented by Mr. Kyriakos BALIDAKIS on 17 Mar 2016 at 12:30
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
In this study, the issue of the quality of meteorological data employed for VLBI data analysis is addressed. Traditionally, ambient barometric pressure and temperature values are used to model the hydrostatic component of the neutral atmospheric propagation delay and the thermal deformation of antennas, in VLBI data analysis. Unlike the other microwave-based space geodetic techniques currently con ... More
Presented by Mr. Kyriakos BALIDAKIS on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
Modern, VGOS and general purpose radio-astronomical digital back ends (DBEs), will produce enormous amounts of data, posing some challenges for the recorders. Fortunately, the availability of ever faster digital hardware has also meant that capturing these large data streams on - relatively speaking - general purpose hardware has become quite feasible. Currently there are two models of ethernet ... More
Presented by Mr. harro VERKOUTER on 14 Mar 2016 at 14:30
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
Broadband Acquisition System (BRAS) was designed to digitize wideband signals from receivers of radio telescopes, pack the digital samples into VDIF frames and transmit them through 10G Ethernet interface. The system has been installed in Badary and Zelenchukskaya observatories on the recently constructed 13-meters RT-13 radio telescopes in February–March 2015. Since November 2016, IAA RAS perfo ... More
Presented by Mr. Evgeny NOSOV on 14 Mar 2016 at 14:00
Type: Poster Presentation Session: Poster1-3
Track: 2: VGOS Strategies and Expected Results
The VLBI Global Observing System (VGOS) has been designed to take advantage of advances in data bandwidths, allowing for smaller and faster antennas, wider bandwidths, and shorter observation durations. Here, schedules for a "realistic" VGOS network, frequency sequences, and expanded source lists are presented using a new source-based scheduling algorithm. VGOS aims for continuous observations whi ... More
Presented by Dr. Bill PETRACHENKO on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
Currently SKA-SA and HartRAO are converting the redundant 34-m telecommunications antenna in Ghana to a radio telescope. The Ghanaian radio telescope will be the second element, HartRAO the first, of what will become the African VLBI Network (AVN). There are 29 documented 30-m class telecommunications antennas in 19 African countries (though some have been destroyed). It is proposed that more of ... More
Presented by Dr. Aletha DE WITT on 15 Mar 2016 at 12:25
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
It is known that the VLBI Global Observing System (VGOS) network suffers from a lack of implementation in the South Pacific area. It is why GRGS was considering setting up a VLBI antenna in Tahiti in cooperation with NASA. There is an existing geodetic observatory (OGT) in the campus of the French Polynesian University (UPF) which was created in 1998 in a tripartite cooperation between UPF, NASA ... More
Presented by Dr. richard BIANCALE on 14 Mar 2016 at 10:35
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
The VLBI group at Technische Universität Wien (TU Wien) is going to run a VLBI software correlator for scientific purposes. For that reason, DiFX is installed on the Vienna Scientific Cluster 3 (VSC-3) consisting of 2020 nodes, each equipped with 2 processors (Intel Xeon E5-2650v2, 2.6 GHz, 8 cores). Of course, only a fraction of the total number of cores will be available for VLBI correlation. T ... More
Presented by Johannes BOEHM on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster4-6
Track: 6: VLBI Observations of Space Vehicles
The successful deployment of the Chang’E-3 Lander on the Moon on Dec 14th, 2013 has opened a new window for VLBI observations of the Moon. Following proposals to the IVS Observing Program Committee, a global IVS R&D network augmented with two China Deep Space Stations was configured for joint observations of the lander in a project called OCEL (Observing the Chang’E-3 Lander with VLBI). From J ... More
Presented by Axel NOTHNAGEL, Rüdiger HAAS on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster1-3
Track: 1: Advances in VGOS Stations and Technology
Very long baseline interferometry (VLBI) is used in geodesy to determine a telescope’s position relative to the galactic centre. A modern, fast slewing radio telescope measuring approximately 13 metres in diameter have been chosen to be used in the VLBI Global Observing System (VGOS), which will help improve the accuracy across global baselines from around 1 cm down to 1 mm. In 2014 HartRAO star ... More
Presented by Prof. Ludwig COMBRINCK on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
The goal of VLBI Ecliptic Plane Survey (VEPS) is to increase the number of calibrator radio sources within 7.5 degree of the ecliptic plane by surveying a complete sample of sources with single dish flux densities at 5 GHz greater than 50 mJy. A dense grid of calibrators along ecliptic plane with very accurate coordinates is required for many applications, including observations of spacecrafts in ... More
Presented by Fengchun SHU on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
February 26th 2015 the United Nations General assembly adopted the resolution on the Global Geodetic Reference Frame (GGRF). Presently major effort under a UN mandate is entered into developing a road map giving guidance to how the GGRF shall become sustainable. This work will influence the geodetic framework conditions in the years to come. As a contribution to global geodesy, Norway is building ... More
Presented by Mr. Per Erik OPSETH on 14 Mar 2016 at 15:10
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
The continuous observing mode envisioned for the new array of VGOS stations would benefit greatly from a high level of automation, from scheduling through to analysis. The centrally-operated AuScope VLBI array of three 12m antennas in Australia is serving as a testbed for these automation techniques. Here we describe the challenges we are addressing, how we are using simulations to undertand where ... More
Presented by Dr. Jim LOVELL on 15 Mar 2016 at 09:45
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
Real-time e-VLBI continues to form an integral element of the European VLBI Network (EVN), accounting for about a quarter of all EVN hours and providing unique rapid-response capabilities to transient events as well as the opportunity for higher-cadence observations compared to the standard EVN sessions that fall three times per year. The EVN software correlator at JIVE (SFXC) can currently proce ... More
Presented by Dr. Bob CAMPBELL on 16 Mar 2016 at 09:45
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The Tsukuba station in Japan is an essential station in the IVS Intensive series for rapid UT1 estimation. The use of this station in rapid UT1 estimation requires a set of best-predetermined station coordinates but the consequences of the Earthquake in Japan in March 2011 were such that the previously known velocity rates of the station Tsukuba were unusable. Since 2012, the VLBI group at BKG u ... More
Presented by Mr. Gerald ENGELHARDT on 14 Mar 2016 at 17:00
on 13 Mar 2016 at 16:00
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
The Geospatial Information Authority of Japan (GSI) has been operating Network Stations such as Tsukuba 32-m antenna, Tsukuba Correlator, and Tsukuba Analysis Center. Recently we started to operate a new VGOS antenna, Ishioka 13-m antenna, which will take over the role of Tsukuba 32-m antenna and, on the other side, stopped operation of the three regional antennas in Japan. GSI is now being active ... More
Presented by Mr. Ryoji KAWABATA on 15 Mar 2016 at 11:55
Type: Oral Presentation Session: Oral4: Data structures and Analysis Strategies in the VGOS Era
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The IERS Conventions contain recommendations, definitions and models for space geodetic techniques including geodetic VLBI. In practice, different analysis software packages follow different estimation methods, use a variety of different correction models and sometimes adhere to conventions that might not be the latest. This may lead to differences in the results that should not appear among the s ... More
Presented by Mr. Grzegorz KLOPOTEK on 16 Mar 2016 at 11:40
Type: Oral Presentation Session: Oral4: Data structures and Analysis Strategies in the VGOS Era
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
Robust and automatic estimation of ambiguities is one of the main requirements for a fully automated analysis of Intensive sessions. We apply the L1-norm minimization to ambiguity estimation and ionosphere calibration using the c5++ analysis software. This study includes IVS Intensive sessions on the Kokee-Wettzell baseline from 2001 to 2015 where Version-1 database are accessible. Version-1 corre ... More
Presented by Mr. Niko KAREINEN on 16 Mar 2016 at 11:25
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
ICRF2 was adopted by the IAU in 2009 and was based on the position of 3414 radio sources determined by VLBI. Discussions on the next realization of the ICRF (ICRF3) have been underway within the IAU and IVS since 2012. VLBI has made significant advances since ICRF2. From the latest GSFC solution, we extract a set of sources that defines a stable celestial reference frame, as shown by M. Feissel-V ... More
Presented by Dr. Karine LE BAIL on 17 Mar 2016 at 09:45
Type: Oral Presentation Session: Oral4: Data structures and Analysis Strategies in the VGOS Era
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The VLBI Global Observing System (VGOS) will present a number of challenges for VLBI data analysis. For example, there will be an increase in the number of observations per day by a factor of 10-30 or even more. Furthermore, another goal of VGOS is to reduce the latency between observation and availability of the results, like the Earth Orientation Parameters (EOP) to less than one day. Ideally, t ... More
Presented by Dr. Tobias NILSSON on 16 Mar 2016 at 11:55
Type: Oral Presentation Session: Oral4: Data structures and Analysis Strategies in the VGOS Era
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The Norwegian Mapping Authority has been using GEOSAT to analyze 24-hour VLBI sessions. GEOSAT was originally developed by Per Helge Andersen at the Norwegian Research Defense Establishment, but is now owned by Norwegian Mapping Authority. GEOSAT is a multi-technique geodetic analysis software that aims to process observations from VLBI, SLR, GNSS and DORIS to improve the global geodetic reference ... More
Presented by Ms. Ann-Silje KIRKVIK on 16 Mar 2016 at 12:10
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The VGOS antenna Ws at Wettzell is equipped with an Elevenfeed, having a continuous frequency range from 2 GHz - 14 GHz. The receiving system with eight parallel intermediate frequency channels enables the use of four bands at different polarizations. A DBBC in combination with a FILA10G and a Mark6 System is used as backend. The presentation gives an overview about the current status of the broad ... More
Presented by Gerhard KRONSCHNABL on 14 Mar 2016 at 12:30
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The current state of the X/S source catalog is presented and compared to ICRF2. There are currently ~60% more observations and ~30% more sessions than were used for ICRF2. An ICRF made today would have ~20% more sources than ICRF2 and the average inflated formal errors would be ~2.4 times better than ICRF2. Much of this improvement has come from the VCS-II campaign on the VLBA, in which the ... More
Presented by Dr. David GORDON on 17 Mar 2016 at 09:15
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
The hardware correlator have been used in Chinese Chang'E missions. Recently, a hardware correlator based on uniboard has been developed. This article presents the development of hardware correlator at SHAO and some results.
Presented by zhijun XU on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
The German Antarctic Receiving Station (GARS) O’Higgins started in the early 1990th with regular VLBI operations. Because of its remote position on the Antarctic Peninsula, the VLBI observation was mostly restricted to the Antarctic summer month. New equipment, a continuous operation by the German Aerospace Center (DLR), and new realizations of observation schedules may open the door for regular ... More
Presented by Mr. Christian PLöTZ on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
KALREF, JPL's KALman filter and smoother for REference Frames, has been used to produce JTRF2014, a combined terrestrial reference frame determined from the input SINEX files submitted by the IVS, IGS, ILRS, and IDS for ITRF2014. Using a Kalman filter and smoother allows the reference frame to be determined sequentially as a time series. Incorporating process noise, determined from geophysical flu ... More
Presented by Dr. Richard GROSS on 16 Mar 2016 at 14:00
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
A first 24-h Italian VLBI geodetic experiment, involving the Medicina, Noto and Matera antennas, shaped as an IVS standard EUROPE, was successfully performed. Starting from the correlator output, a geodetic database was created and a typical solution of a small network was achieved, here presented. From this promising result, we have planned new observations in 2016, involving the three Italian ge ... More
Presented by Mr. Matteo STAGNI on 16 Mar 2016 at 09:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
During the Chinese Lunar Mission hundreds of VLBI observations have been carried, we re-analysis all the quasar observations which used to calibrate the satellite observables. In each observation there are two quasar scans lasting about one hour, we use these data by splitting them into different time intervals and doing self-calibration each other in phase-referencing style to investigate the rel ... More
Presented by Mr. Shuangjing XU on 17 Mar 2016 at 12:00
Type: Poster Presentation Session: Poster1-3
Track: 2: VGOS Strategies and Expected Results
In February 2015 the UN General Assembly adopted the resolution “A Global Geodetic Reference Frame for Sustainable Development” - the first resolution recognizing the importance of a globally-coordinated approach to geodesy. The GGRF Working Group is working on the development of a roadmap that will describe how governments can contribute to the sustainability and enhancement of the Global Geo ... More
Presented by Dr. Halfdan Pascal KIERULF on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
Observations at X/Ka-band are motivated by their ability to access more compact source morphology and reduced core shift relative to observations at the historically standard S/X-band. In addition, the factor of four increase in interferometer resolution at Ka-band should resolve out some wide binary black holes which are a topic of concern for AGN centroid stability. Given these motivations ... More
Presented by Mr. Christopher JACOBS on 17 Mar 2016 at 10:15
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
Radio sources observed in global IVS sessions are mostly flat-spectrum radio-loud quasars. While some quasars appear almost point like, many have extended jet components in addition to compact cores. The structure of these jets often varies on timescales of months to years as the black hole at the centre of the quasar accretes new material and ejects components of radio-emitting plasma. These comp ... More
Presented by Dr. Shabala STANISLAV on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
We present the first field-test of the implementation of a coherent optical fiber link for remote antenna synchronization realized in Italy between the Italian Metrological Institute (INRIM) and the Medicina radio observatory. The Medicina VLBI antenna participated to the Eur137 experiment carried out in September 2015, in tag along mode, using, as reference systems, both the local H maser and a ... More
Presented by Mr. Matteo STAGNI on 16 Mar 2016 at 10:30
Type: Poster Presentation Session: Poster1-3
Track: 1: Advances in VGOS Stations and Technology
The Kashima 34 m radio telescope, the cassegrain optics is currently realized 3.2GHz to 14 GHz receiver system by installing the NINJA feed. Furthermore a direct sampler GALAS easily connect four 1GHz bandwidth without any analogue frequency converter and phase-cal. VGOS, EHT and other astronomy VLBI highly demand broadband system for better delay determination, shorter integration time and bett ... More
Presented by Dr. Kazuhiro TAKEFUJI, Dr. Mamoru SEKIDO on 14 Mar 2016 at 15:45
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The Hartebeesthoek Radio Astronomy Observatory (HartRAO) participates in astronomic, astrometric and geodetic Very Long Baseline Interferometry (VLBI) observations using both 26- and 15-m diameter radio telescopes. These as well as additional geodetic data from a Satellite Laser Ranger (SLR), Global Navigation Satellite System (GNSS), Met4 weather stations, a new seismic network must be stored at ... More
Presented by Ms. Glenda COETZER on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The Seshan VGOS station is now in building. It is a very-fast-slewing 13.2m antenna, with QRFH wideband feed, and a realtime 3D measurement system of reference point variation is planing to install. And it locates in the yard of Tianma 65m radio telescope. Its recent progress will be introduced in this report.
Presented by Dr. Guangli WANG on 14 Mar 2016 at 11:30
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
Abstract: Shanghai Astronomical Observatory(SHAO) has started to development VLBI digital backend in 2004. And since 2010, the first generation of digital backends named CDAS(Chinese VLBI Data Acquisition System) have been installed in CVN VLBI stations and applied in several projects. This presentation will introduce the history, the current status and the future of the VLBI digital backends deve ... More
Presented by Mr. renjie ZHU on 16 Mar 2016 at 10:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The CONT14 campaign features state-of-art VLBI data. Therein, the radio source 0642+449 was observed with about one thousand observables each day during the continuous observing period of fifteen days, providing tens of thousands of closure delays, the sum of the delays around a closed loop of baselines. The closure delay is independent of the instrumental and propagation delays and provides valua ... More
Presented by Dr. Minghui XU on 17 Mar 2016 at 11:30
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
Very Long Baseline Interferometry is the only technique that can estimate Earth nutations with an accuracy under the milliarcsecond level. With 35 years of geodetic VLBI observations, the principal nutation terms caused by luni-solar tides and geophysical response have been estimated. We focuse on the variabity. Two of them present very significant amplitude and phase variations : the retrograde F ... More
Presented by Mr. César GATTANO on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
This presentation is dedicated to the influence of diurnal atmosphere-ocean dynamics on Earth rotation and loading effects as observed by Very Long Baseline Interferometry. The first part focuses on the rotational signals associated with atmospheric tides, comprising small but non-negligible oscillations in the order 5 Μas. Here, we compare tidally analysed VLBI observations against estimates f ... More
Presented by Mrs. Anastasiia GIRDIUK on 17 Mar 2016 at 15:00
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The IVS Working Group 4 developed the new format to store and exchange data obtained from geodetic VLBI observations. The new data format, vgosDb, will replace existing Mk4 databases this year. At the GSFC NASA we developed software that will implement vgosDb format and will be used routinely to convert correlator output to the new data storage format. On this poster we present the vgosDb capable ... More
Presented by Dr. John GIPSON on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
In 2007 the Geospatial Information Authority of Japan (GSI) and the Onsala Space Observatory (OSO) started a collaboration project aiming at determining the earth rotation angle, usually expressed as UT1-UTC, in near real-time. In the beginning of this project dedicated one hour long one-baseline experiments were observed periodically using the VLBI stations Onsala (Sweden) and Tsukuba (Japan). Th ... More
Presented by Rüdiger HAAS on 17 Mar 2016 at 14:30
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
MIT Haystack Observatory, as part of the NASA Space Geodesy Program, is delivering the first VGOS-compliant Signal Chain to the Kokee Park Geophysical Observatory (KPGO), Hawaii, and will soon be integrating and commissioning the KPGO 12-m station. We will describe the Signal Chain subsystems and highlight the design and performance of the cryogenically cooled frontend. This incorporates a broa ... More
Presented by Mr. Ganesan RAJAGOPALAN on 14 Mar 2016 at 12:15
Type: Poster Presentation Session: Poster1-3
Track: 3: Stations, Correlators, and Operations Centers
An update of the deployment and activities at the Spanish/Portuguese RAEGE project (“Atlantic Network of Geodynamical and Space Stations”) is presented. Regular observations with Yebes radio telescope are ongoing. Commissioning of the radio telescope at Santa Maria is advanced, and site works for a new station in Tenerife (Canary Islands) have started. Technological developments on receivers f ... More
Presented by Dr. Pablo DE VICENTE on 14 Mar 2016 at 15:45
Type: Oral Presentation Session: Oral3: Stations, Correlators and Operations Centres
Track: 3: Stations, Correlators, and Operations Centers
According to increasing the number of observations by 1-Gbps recording, geodetic VLBI solutions of VERA improve the accuracy. This is for guaranteeing the accuracy of VERA astrometry. However, much more increase in the number of observations is already difficult by the limit of the driving performance of the VERA antenna. OCTAVE series is a candidate of a next-generation data processing system in ... More
Presented by Dr. Takaaki JIKE on 15 Mar 2016 at 12:10
Type: Oral Presentation Session: Oral2: VGOS Strategies and Expected Results
Track: 2: VGOS Strategies and Expected Results
Source structure has long been recognized as a significant risk factor for the broadband method. The issue of greatest concern is that structure related phases and delays will lead to cycle slips during broadband phase connection. These errors will be difficult to handle since they are both subtle to detect and almost certainly impossible to correct after the fact. As the advent of VGOS operati ... More
Presented by Dr. Bill PETRACHENKO on 15 Mar 2016 at 09:15
on 18 Mar 2016 at 14:00
Type: Oral Presentation Session: Oral1: Advances in VGOS Stations and Technology
Track: 1: Advances in VGOS Stations and Technology
The GGAO 12m and Westford 18m antennas are instrumented with the broadband signal chain to provide VGOS capability. These antennas have been making VGOS geodetic observations for more than a year. Approximately seventeen one- to twenty-four-hour VGOS sessions were conducted in 2015 to develop and test many of the procedures needed for an operational program, including scheduling, unattended obse ... More
Presented by Dr. Arthur NIELL on 14 Mar 2016 at 11:45
Type: Poster Presentation Session: Poster4-6
Track: 6: VLBI Observations of Space Vehicles
VLBI technique was used in China’s Lunar Exploration Project Since the Chang’E-1 launched in the year of 2007, after then VLBI was played an important role in the series of Chang’E missions, CE-2, CE-3 and CE-5T1, and will be continued in the future space mission. The observation network consists of Shanghai 25m&65m, Beijing 50m, Kunming 40m and Urumqi 25m radio telescopes. Up to now it stil ... More
Presented by Dr. Guangli WANG on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral6: VLBI observations of Space Vehicles
Track: 6: VLBI Observations of Space Vehicles
The observation of GNSS satellites with the geodetic VLBI system is an interesting approach which offers a variety of new possibilities. Promising applications can be found, among others, in the field of inter technique ties. Such observations provide possibilities to directly connect the dynamic GNSS and the kinematic VLBI reference frame, which may result in improved future ITRF realizations. In ... More
Presented by Mr. Andreas HELLERSCHMIED on 17 Mar 2016 at 16:15
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
ESOC’s Navigation Support Office is providing the geodetic reference for ESA missions and as leader of the Galileo Geodetic Service Provider (GGSP) consortium, also for Galileo. The Navigation Support Office has demonstrated its expertise in the processing of various space-geodetic techniques, such as GNSS, SLR and DORIS and their combination on the observation level. Nevertheless, the last and ... More
Presented by Ms. Claudia FLOHRER on 16 Mar 2016 at 14:30
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
Until now, the main criteria for selecting geodetic sources were based on astrometric stability and structure at 8 GHz [Fey et al., 2015]. Other physical characteristics, especially at other wave-lengths, including the optical, should also enter the selection procedure. To this aim, we propose to summarize all known physical caracteristics, thanks to the use of three different catalogs : the Large ... More
Presented by Mr. César GATTANO on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster4-6
Track: 6: VLBI Observations of Space Vehicles
The ESA Venus and Mars Express spacecrafts were observed at X-band with the Wettzell radio telescopes Wn and Wz in a framework of the assessment study of the possible contribution of the European VLBI network to the upcoming ESA deep space missions and further projects. These observations were extended to regular weekly sessions to routinely run the processing and analysis pipeline. Recorded data ... More
Presented by Dr. Alexander NEIDHARDT on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
The Vienna VLBI Software (VieVS) is a VLBI analysis software developed and maintained at Technische Universität Wien (TU Wien) since 2008 with contributions from groups all over the world. It is used for both academic purposes in university courses as well as for providing VLBI analysis results to the geodetic community. Written in a modular structure in Matlab, VieVS offers easy access to the so ... More
Presented by Johannes BöHM on 14 Mar 2016 at 17:00
Type: Poster Presentation Session: Poster4-6
Track: 5: Geodetic and Astrometric VLBI Results
The next realisation of the International Terrestrial Reference System, the ITRF2014, is currently in preparation or under evaluation, respectively. The VLBI input to ITRF2014 is provided by the International VLBI Service for Geodesy and Astrometry (IVS) and consists of a combination of all analysis center contributions. One of these single solutions is contributed by the Vienna special analysis c ... More
Presented by Johannes BOEHM on 14 Mar 2016 at 17:00
Type: Oral Presentation Session: Oral5: Geodetic and Astrometric Results
Track: 5: Geodetic and Astrometric VLBI Results
The current realisation of the celestial reference frame, the ICRF2, was published 2009. Since then the VLBI technique evolved. New stations were implemented and the amount of data from the Southern Hemisphere increased dramatically. The demands on accuracy of the celestial reference frame are higher than ever, with the GAIA mission providing a catalogue in the visible spectrum with comparable acc ... More
Presented by Mr. David MAYER on 17 Mar 2016 at 09:00
on 14 Mar 2016 at 18:30
on 18 Mar 2016 at 16:00
Type: Poster Presentation Session: Poster4-6
Track: 4: Data Structures and Analysis Strategies in the VGOS Era
Although several fully developed VLBI software packages exist already, the VLBI group of the Institute of Geodesy and Geoinformations of Bonn University (ivg) started implementing a new analysis toolbox. The main reason is the need for a flexible environment, which allows for straightforward implementations of new scientific and software-related ideas for VLBI data analysis. Furthermore, we wanted ... More
Presented by Dr. Thomas ARTZ on 14 Mar 2016 at 17:00