A high power 53 MHz Mesosphere-Stratosphere-Troposphere (MST) Radar was established in 1992 as a national facility for atmospheric research at National Atmospheric Research Laboratory (NARL), Department of Space Govt. of India Gadanki. The MST Radar is a state-of-the-art instrument capable of providing estimates of atmospheric parameters with very high resolution on a continuous basis.

As part of the silver jubilee of the establishment of the high power MST Radar, NARL organised the third Regional Conference on Radio Science 2017 (URSI-RCRS 2017) during March 1-4, 2017 at Tirupati, jointly with the Indian Committee for URSI (INCURSI) under the Indian National Science Academy (INSA).

International Union of Radio Science (URSI) promotes all aspects of radio science under ten Commissions - Electromagnetic Metrology, Fields and Waves, Radio Communication Systems and Signal Processing, Electronics and Photonics, Electromagnetic Environment and Interference, Wave Propagation and Remote Sensing, Ionospheric Radio and Propagation, Waves in Plasmas, Radio Astronomy, Electromagnetics in Biology and Medicine.

INCURSI started this series of conferences covering Africa and South Asian region to encourage and promote radio science research as well as interdisciplinary interaction among researchers from the sub-fields of radio science, at a periodicity of about eighteen months. The first conference was organised in January 2014 at Symbiosis University, Pune and the second conference in November 2015 at Jawaharlal Nehru University, New Delhi. The number of delegates have been increasing and the present conference has more than 280 registered participants. A total of 200 papers were presented in ten Commissions during URSI-RCRS 2017, out of which 26 were invited talks, 79 contributed talks and 95 posters presentations.

A special session to mark the beginning of the silver jubilee year of Indian MST Radar was organised at the conference, which talks about the origin, design, development, installation and utilisation of the radar were presented by the engineers and scientists associated with it. A detailed exposition of the initiation of the idea of ground based remote sensing of Earth atmosphere under Indian Middle Atmosphere Programme was provided during the conference. Intricacies and challenges of low radio noise site selection, project design, implementation and operational phases over past 25 years, were described by the associated senior and young scientists and engineers.

Young Scientist (YSA) and Student Paper Competition (SPC) awards are a special feature of URSI-RCRS, wherein young scientists under the age of 35 years and students registered for Ph.D or M.Tech Students with some research experience are encouraged to participate in the conference by submitting good quality papers and prizes are given. There were 21 YSA entries out of which eight were shortlisted for final presentation. Five YSA prizes were awarded (1st , 2nd, 3rd and two honorable mention). For SPC, there were 25 entries out of which 10 were shortlisted for final presentations. Five SPC prizes were awarded (1st , 2nd, 3rd and two honorable mention).

The conference sessions during first three days are conducted at Fortune Select Grand Ridge Hotel, Tirupati. The final day's sessions were organised at NARL Gadanki, to give the participants an exposure of experimental facilities of NARL. In the valedictory session, it was mentioned by the general chairs that the third URSI-RCRS had given a tremendous boost to radio science and that it would now serve as an excellent impetus to the forthcoming URSI Asia Pacific Radio Science Conference (AP-RASC 2019) to be held in New Delhi during March 9-15, 2019. The Commission chairs appreciated the participation of many new young scientists apart from distinguished scientists from India and abroad and the excellent organisation of the conference.

The third URSI-RCRS was inaugurated by Sri A.S. Kiran Kumar, Chairman ISRO on March 01, 2017 at Tirupati. He elaborated on the emerging opportunities in semiconductors, remote sensing, frontline propulsion systems, nano and micro satellites. He gave a call to the serious researchers, young scientists and students to take up the challenging problems in these emerging areas and reiterated the strong support and commitment of ISRO to the advancement of radio science in the country.

Chairman, ISRO, also released a video documentary on NARL and unveiled the announcements of the two forthcoming conferences planned during the silver jubilee year of Indian MST Radar, namely, "Understanding, Predicting and Projecting Climate Change over Indian Region (UPCAR)" during June 26-28, 2017, in collaboration with SV University Tirupati and "India Radar Meteorology (IRad) Conference" during January 08-11, 2018 in collaboration with Ministry of Earth Sciences (MoES), Govt of India.

Inauguration of URSI-RCRS 2017 by Chairman ISRO