Reconfigurable floating-point operation device based on CORDIC algorithm

Abstract

A reconfigurable floating-point arithmetic device based on CORDIC algorithm comprises a preprocessing module for completing input data from IEEE-754 standard, and maps it into the convergence region;a series-parallel hybrid reconfigurable CORDIC iterative unit module. The iterative operation part of CORDIC algorithm is composed of two parts: rotation modules A and B, wherein, the rotation moduleA is used to realize serial pipeline structure to maximize module reuse, the rotation module B is based on parallel prediction method of rotation direction and adopts tree adder structure to realize parallel structure in rotation mode; in the post-processing module, the corresponding result output is selected according to the encoded signal of the pre-processing module, and the mantissa normalization processing is completed to output the single-precision floating-point data format calculation result. The invention has the characteristics of simple principle, low delay, high precision and low hardware cost.

Description

technical field [0001] The invention belongs to the technical field of a floating-point arithmetic unit in radar real-time imaging processing, and in particular relates to a reconfigurable floating-point arithmetic device based on a CORDIC algorithm. Background technique [0002] In the real-time imaging processing of on-board synthetic aperture radar (SAR), in order to achieve higher resolution, a large amount of data needs to be stored and downloaded, and the imaging processing algorithm has a huge amount of computation, which not only poses a challenge to real-time processing , but also brought great difficulties to the hardware implementation. In particular, the calculation of the phase compensation factor in the Chirp Scaling (CS) algorithm includes multiple nonlinear operations such as single-precision floating-point trigonometric functions and square root. These operations are generally implemented on hardware by methods such as lookup table, polynomial fitting, and ...

AI Technical Summary

Problems solved by technology

However, the traditional CORDIC algorithm has problems such as limited convergence range and long algorithm delay. Repeating certain iterations can expand the convergence domain, but it will cause the scaling factor to be non-constant, requiring additional hardware logic to operate. Scaling-Free CORDIC The algorithm adopts the method of Taylor series approximation, which can avoid the calculation of the scaling factor and reduce the number of iterations. However, most of this method is applied to the fixed-point CORDIC operation, which cannot meet the calculation accuracy of the Chirp Scaling algorithm.

[0004] Since the CORDIC algorithm needs to be in different coordinate systems and different modes when implementing different operations, most of the existing calculators based on the CORDIC algorithm can only work in a single coordinate system and rotation mode to achieve a certain type of operation. When implementing multiple operations for some specific applications, multiple processors are often required

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