High-precision parallel implementation method of digital NCO based on GPU

Abstract

The invention discloses a high-precision parallel realization method of a digital NCO based on a GPU, belongs to the field of communication technology, and can design and realize a high-efficiency and high-precision numerical control oscillator NCO. The method specifically includes: constructing a sine lookup table LUT, and storing the sine lookup table LUT by using a texture cache of a graphics processor GPU. The graphics processing unit GPU receives input data and processes it in segments. In each segment, after determining the initial phase of the current segment, calculate the phase value of each data point for each data point in the segment according to the phase difference value of the sampling point; and cancel the phase value of the last data point in the segment After the whole cycle of operation, the phase difference value of the sampling point is added as the initial phase of the next segment; thus, the accumulated phase value of each data point of the input data is obtained. The index value index (iL) of the lookup table is constructed by using the accumulated phase value of the data points, and the sine and cosine quadrature digitally controlled oscillator NCO signals are obtained by searching from the sine lookup table LUT in the texture cache.

Description

technical field [0001] The invention relates to the field of communication technology, in particular to a GPU-based high-precision parallel implementation method of a digital NCO. Background technique [0002] Digital Down Converter (DDC) system is an important subsystem of modern aerospace measurement and control system. In a typical DDC system, the digital local oscillator is the most complex core device. [0003] In a traditional DDC system, the digital local oscillator is mainly realized by a numerical control oscillator (Numerical Control Oscillator, NCO). A typical NCO consists of an N-bit phase accumulator, a phase register, and an M-bit sine look-up table. Increasing the number of N and M bits can effectively improve the frequency and phase resolution, but the phase resolution accuracy of the lookup table is limited by the storage space on the FPGA chip and cannot be effectively improved. In recent years, with the increase of on-chip storage space, the look-up tab...

AI Technical Summary

Problems solved by technology

[0005] Although the GPU-based NCO implementation method has the advantages of flexibility and high efficiency, the GPU-based floating-point number calculation method will accumulate errors due to the rounding error of the floating-point number operation in the phase accumulation process.

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