www.tjprc.org editor@tjprc.org A SURVEY OF THE APPLICATIONS OF MULTILATERATION IN CIVIL AVIATION D. ESWARA CHAITANYA 1 , S. SUDHA RANI 2 , G. SASIBHUSHANA RAO 3 & RAJKUMAR GOSWAMI 4 1 Department of E.C.E, ANITS, Sangivalasa, Visakhapatnam, Andhra Pradesh, India 2 DLRL, Hyderabad, Andhra Pradesh, India 3,4 Department of E.C.E, Andhra University College of Engineering, Visakhapatnam, Andhra Pradesh, India ABSTRACT Determination of unambiguous real time position information is one of the primary concerns of civilian applications such as air traffic control as well as defence requirements involving modern Electronic Warfare systems. Civilian air traffic control is facing the problem of huge infrastructure costs due to the requirement of additional avionics equipment onboard the aircraft necessitated by the use of traditional radar systems. Also the update rate of radar derived targets on the controller screen is low resulting in ambiguous resolution of targets. All these and many more issues can be addressed by the wise use of the concept of multilateration. The distinguishing feature of hyperbolic multilateration systems is that the position is estimated from differential arrival times of a pulse transmitted over several distinct paths. Thus no absolute time reference is required. In this paper, the applications of multilateration systems are discussed in detail with emphasis on the civil aviation sector. KEYWORDS: Hyperbolic, Multilateration, TDOA, Aviation Received: Jan 17, 2017; Accepted: Feb 07, 2017; Published: Feb 15, 2017; Paper Id.: TJPRC:IJSPSJUN20172 INTRODUCTION The position location techniques used for location of moving targets employ the hyperbolic position location technique, which is also known as the time difference of arrival (TDOA) position determination method. This technique is also known as hyperbolic multilateration that is used in general for 3-D position determination of an unknown target. A TDOA based positioning method involves two main steps. It was chosen because of its relatively high accuracy despite the fact that it does not require information about the transmitted signal. In the first step, the time differences of arrivals of the signal of interest to the different sensors are measured [1]. This can be done by cross correlation and peak detection of the sensors’ signals. In the second step, the measured TDOAs are used to solve the hyperbolic system. The intersection of hyperbolas from multiple TDOAs yields the transmitter position. Due to measurement errors, the hyperbolas shift and yield multiple intersection points. The position estimation aims at minimizing the square error. Traditional radars and GPS based systems are unable to withstand the enormous demand brought upon by advances in technology and this is where the multilateration technique comes into picture. This paper is divided into 4 sections. The second section introduces the method of hyperbolic multilateration. The third section discusses the various applications of TDOA positioning with an emphasis on the civil aviation sector. In section 4, the conclusions pertaining to the discussion that follows are presented. Original Article TJPRC: International Journal of Signal Processing Systems (TJPRC: IJSPS) Vol. 1, Issue 1, Jun 2017, 13-18 © TJPRC Pvt. Ltd.