International Journal of Innovative Technology and Exploring Engineering (IJITEE) ISSN: 2278-3075, Volume-2, Issue-5, April 2013 34 Abstract: A technique is allocated going to discuss the application of cordic algorithm in avionics. Actually here the process is dealing with avionics so, the smart application of cordic algorithm is in ARM processor. In GNSS (global navigation satellite system) receiver make use of ARM processor floating point instruction (FPI) are there to calculate the FPI. It contains floating point unit (FPU). So, to make easy calculation in FPU have implemented cordic algorithm here cordic calculation means calculating trigonometric values. In this way FPU has implemented. Here trigonometric values means sin, cosine, tangent after getting tangent values have to see timing response of the binary output. So, in navigation system. Now, accurate signals have been sensed. Without any critical path delay then automatically speed will increase delay will reduce this is more advantage in avionics system. For floating point addition, exponent matching and shifting of 24 bit mantissa and sign logic are coded in behavioral style. Prototypes are implemented on Xilinx vertex-4 and 5. By designing pipelining in cordic and wave pipelining in cordic is implemented in cordic algorithm to reduce the timing response in the navigation system. Index terms – fpu, cordic algorithm, pipelining and wave pipelining in cordic, avionics. I. INTRODUCTION Cordic (co-ordinate rotation digital computer) algorithm is a hardware efficient algorithm. It is an iterative in nature and is implemented in terms of rotation matrix. It can perform a rotation with the help of a series of incremental rotation angles each of which is performed by a shift and add/sub operation. Evaluation of trigonometric values sine, cosine, and tangent is generally a complex operations which requires a lot of memory has complex algorithm and requires a large number of clock cycles with expensive hardware organization. But the algorithm that is use here is absolutely simple with very low memory requirements faster calculation and commendable precision which use only bit shifting operation and add/sub operation to compute any function. CORDIC (Coordinate Rotation Digital Computer) is a simple and hardware-efficient algorithm for the implementation of various elementary, especially trigonometric, functions. Instead of using Calculus based methods such as polynomial or rational functional approximation, it uses simple shift, add, subtract and table look-up operations to achieve this objective. Manuscript received on April, 2013. Chowdi Ravitej, , Chowdi Ravitej, Electronics and Communication Engineering, Sathyabama University,/Chennai/India. Elphesj Churchill, Elphej Churchill, Electronics and Communication Engineering, Sathyabama University,/Chennai/India. Kishore Sonti, vjk. kishore sonti, Electronics and communication Engineering, sathyabama University,/Chennai/India. The implementation of cordic algorithm is as follows:  Three registers for the values of xi,yi,zi.  Shifter for implementation of 2 -i .  Adder/subtraction blocks for arithmetic operations are there as per di (direction) value these values are got from alpha i=tan(2 -i ). Fig: 1.1: Block diagram of cordic algorithm The arc tan values are calculated by arc tan(1/2 n ) for calculating number of iterations in cordic algorithm for one iteration cordic requires approximately two shifts and the three add/sub operations all required the functions of the cordic algorithm is carried out in the cordic core block to calculate each and every iteration the value of angle accumulator arc tan will be compared with given angle then the remaining angle of rotation will be calculated after comparison and the result is feedback to the input arc tan. The above is repeated to all specified iterations for outputs dx, dy is the feedback input to xi, yi after the n iterations the values. Cordic algorithms is only shift and add/sub computing algorithm it can perform various functions cordic based VLSI architectures provides a better alternative to the architectures based on multiply and add/sub hardware mainly cordic algorithm is used for reducing the complexity of the circuit it is main application in aircraft navigation process. By implementing the cordic algorithm complexity of the circuit will be reduced because of one bit shifting and add/sub operations and timing response will be reduced area will be decreased this all advantage by using cordic algorithm. The application of cordic algorithm in floating point unit reduced area and improved the speed and reduced delay. And it provides a better design architecture for further designs. Hence by reducing these major factors like area and delay. Is more advantage in real time process. Design and Simulation of Cordic Co-Processor and Its Application in Avionics Chowdi Ravitej, Elphesj Churchill, Kishore Sonti