Dr. Radhakrishnan is recipient of numerous accolades including “Distinguished Alumnus Award” of IIT Kharagpur (2010) and IIM Bangalore (2010); Vikram Sarabhai Memorial Award of Indian Science Congress.(2010); Athivishishta Rajakeeya Puraskaram – "Sastra Ratna" by the Pazhassiraja Charitable Trust (2010); Social Sciences Award (2009) of the International Academy of Astronautics; Dr. Y. Nayudamma Memorial Award of Andhra Pradesh Academy of Sciences (2009); BHASKARA Award of Indian Society of Remote Sensing (2008); Silver Jubilee Honour by Ministry of Earth Sciences (2006); VASVIK Industrial Research Award in the field of Electrical and Electronics Sciences & Technology (2005); and K.R. Ramanathan Memorial Gold Medal of Indian Geophysical Union (2003).

Dr. Radhakrishnan has been conferred Honorary Doctorates by Sri Venkateswara University, Tirupati; Rajasthan Technical University, Kota; GITAM University, Visakhapatnam, Tumkur University and SRM University, Chennai in 2010. KIIT University, Bhubaneswar have invited him to confer with Honorary Doctorate in December 2010.

He is a Fellow of Indian National Academy of Engineering (FNAE); Honorary Life Fellow of The Institution of Engineers, India; Honorary Fellow of The Institution of Electrical and Telecommunication Engineers, India; Member of International Academy of Astronautics, Fellow of Andhra Pradesh Academy of Sciences, Fellow of Indian Society of Remote Sensing; Fellow of Indian Geophysical Union.

He was President of Indian Society of Remote Sensing during 2007-09 and Vice President of Indian Geophysical Union during 2007-09. He is the current President of Astronautical Society of India.