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										 |  |  | ///////////////////////////////////////////////////////////////////////////////////
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							|  |  |  | // Copyright (C) 2018 F4EXB                                                      //
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							|  |  |  | // written by Edouard Griffiths                                                  //
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							|  |  |  | //                                                                               //
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							|  |  |  | // FFT based cross correlation                                                   //
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							|  |  |  | //                                                                               //
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							|  |  |  | // See: http://liquidsdr.org/blog/pll-howto/                                     //
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							|  |  |  | // Fixed filter registers saturation                                             //
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							|  |  |  | // Added order for PSK locking. This brilliant idea actually comes from this     //
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							|  |  |  | // post: https://www.dsprelated.com/showthread/comp.dsp/36356-1.php              //
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							|  |  |  | //                                                                               //
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							|  |  |  | // This program is free software; you can redistribute it and/or modify          //
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							|  |  |  | // it under the terms of the GNU General Public License as published by          //
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							|  |  |  | // the Free Software Foundation as version 3 of the License, or                  //
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											2019-04-11 14:32:15 +02:00
										 |  |  | // (at your option) any later version.                                           //
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										 |  |  | //                                                                               //
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							|  |  |  | // This program is distributed in the hope that it will be useful,               //
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							|  |  |  | // but WITHOUT ANY WARRANTY; without even the implied warranty of                //
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							|  |  |  | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                  //
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							|  |  |  | // GNU General Public License V3 for more details.                               //
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							|  |  |  | //                                                                               //
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							|  |  |  | // You should have received a copy of the GNU General Public License             //
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							|  |  |  | // along with this program. If not, see <http://www.gnu.org/licenses/>.          //
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							|  |  |  | ///////////////////////////////////////////////////////////////////////////////////
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							|  |  |  | #ifndef SDRBASE_DSP_FFTCORR_H_
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							|  |  |  | #define SDRBASE_DSP_FFTCORR_H_
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							|  |  |  | #include <complex>
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							|  |  |  | #include "gfft.h"
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							|  |  |  | #include "export.h"
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							|  |  |  | class SDRBASE_API fftcorr { | 
					
						
							|  |  |  | public: | 
					
						
							|  |  |  |     typedef std::complex<float> cmplx; | 
					
						
							|  |  |  |     fftcorr(int len); | 
					
						
							|  |  |  |     ~fftcorr(); | 
					
						
							|  |  |  | 
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							|  |  |  |     int run(const cmplx& inA, const cmplx* inB, cmplx **out); //!< if inB = 0 then run auto-correlation
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										 |  |  |     const cmplx& run(const cmplx& inA, const cmplx* inB); | 
					
						
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							|  |  |  | private: | 
					
						
							|  |  |  |     void init_fft(); | 
					
						
							|  |  |  |     int flen;  //!< FFT length
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										 |  |  |     int flen2; //!< half FFT length
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										 |  |  |     g_fft<float> *fftA; | 
					
						
							|  |  |  |     g_fft<float> *fftB; | 
					
						
							|  |  |  |     cmplx *dataA;  // from A input
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							|  |  |  |     cmplx *dataB;  // from B input
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							|  |  |  |     cmplx *dataBj; // conjugate of B
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							|  |  |  |     cmplx *dataP;  // product of A with conjugate of B
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							|  |  |  |     int inptrA; | 
					
						
							|  |  |  |     int inptrB; | 
					
						
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										 |  |  |     int outptr; | 
					
						
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										 |  |  | }; | 
					
						
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							|  |  |  | #endif /* SDRBASE_DSP_FFTCORR_H_ */
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