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22 #ifndef _GRI_MMSE_FIR_INTERPOLATOR_CC_H_
23 #define _GRI_MMSE_FIR_INTERPOLATOR_CC_H_
25 #include <gr_complex.h>
31 * \brief Compute intermediate samples between signal samples x(k*Ts)
32 * \ingroup filter_primitive
34 * This implements a Mininum Mean Squared Error interpolator with 8 taps.
35 * It is suitable for signals where the bandwidth of interest B = 1/(4*Ts)
36 * Where Ts is the time between samples.
38 * Although mu, the fractional delay, is specified as a float, it is actually
39 * quantized. 0.0 <= mu <= 1.0. That is, mu is quantized in the interpolate
40 * method to 32nd's of a sample.
43 class gri_mmse_fir_interpolator_cc {
45 gri_mmse_fir_interpolator_cc ();
46 ~gri_mmse_fir_interpolator_cc ();
48 unsigned ntaps () const;
49 unsigned nsteps () const;
52 * \brief compute a single interpolated output value.
54 * \p input must have ntaps() valid entries and be 8-byte aligned.
55 * input[0] .. input[ntaps() - 1] are referenced to compute the output value.
56 * \throws std::invalid_argument if input is not 8-byte aligned.
58 * \p mu must be in the range [0, 1] and specifies the fractional delay.
60 * \returns the interpolated input value.
62 gr_complex interpolate (const gr_complex input[], float mu);
65 std::vector<gr_fir_ccf *> filters;
69 #endif /* _GRI_MMSE_FIR_INTERPOLATOR_CC_H_ */