arm_lms_norm_init_q15.c
101 lines
| 3.0 KiB
| text/x-c
|
CLexer
jeandet@pc-de-jeandet3.lab-lpp.local
|
r16 | /*----------------------------------------------------------------------------- | ||
| * Copyright (C) 2010 ARM Limited. All rights reserved. | ||||
| * | ||||
| * $Date: 29. November 2010 | ||||
| * $Revision: V1.0.3 | ||||
| * | ||||
| * Project: CMSIS DSP Library | ||||
| * Title: arm_lms_norm_init_q15.c | ||||
| * | ||||
| * Description: Q15 NLMS initialization function. | ||||
| * | ||||
| * Target Processor: Cortex-M4/Cortex-M3 | ||||
| * | ||||
| * Version 1.0.3 2010/11/29 | ||||
| * Re-organized the CMSIS folders and updated documentation. | ||||
| * | ||||
| * Version 1.0.2 2010/11/11 | ||||
| * Documentation updated. | ||||
| * | ||||
| * Version 1.0.1 2010/10/05 | ||||
| * Production release and review comments incorporated. | ||||
| * | ||||
| * Version 1.0.0 2010/09/20 | ||||
| * Production release and review comments incorporated | ||||
| * | ||||
| * Version 0.0.7 2010/06/10 | ||||
| * Misra-C changes done | ||||
| * ---------------------------------------------------------------------------*/ | ||||
| #include "arm_math.h" | ||||
| #include "arm_common_tables.h" | ||||
| /** | ||||
| * @addtogroup LMS_NORM | ||||
| * @{ | ||||
| */ | ||||
| /** | ||||
| * @brief Initialization function for Q15 normalized LMS filter. | ||||
| * @param[in] *S points to an instance of the Q15 normalized LMS filter structure. | ||||
| * @param[in] numTaps number of filter coefficients. | ||||
| * @param[in] *pCoeffs points to coefficient buffer. | ||||
| * @param[in] *pState points to state buffer. | ||||
| * @param[in] mu step size that controls filter coefficient updates. | ||||
| * @param[in] blockSize number of samples to process. | ||||
| * @param[in] postShift bit shift applied to coefficients. | ||||
| * @return none. | ||||
| * | ||||
| * <b>Description:</b> | ||||
| * \par | ||||
| * <code>pCoeffs</code> points to the array of filter coefficients stored in time reversed order: | ||||
| * <pre> | ||||
| * {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]} | ||||
| * </pre> | ||||
| * The initial filter coefficients serve as a starting point for the adaptive filter. | ||||
| * <code>pState</code> points to the array of state variables and size of array is | ||||
| * <code>numTaps+blockSize-1</code> samples, where <code>blockSize</code> is the number of input samples processed | ||||
| * by each call to <code>arm_lms_norm_q15()</code>. | ||||
| */ | ||||
| void arm_lms_norm_init_q15( | ||||
| arm_lms_norm_instance_q15 * S, | ||||
| uint16_t numTaps, | ||||
| q15_t * pCoeffs, | ||||
| q15_t * pState, | ||||
| q15_t mu, | ||||
| uint32_t blockSize, | ||||
| uint8_t postShift) | ||||
| { | ||||
| /* Assign filter taps */ | ||||
| S->numTaps = numTaps; | ||||
| /* Assign coefficient pointer */ | ||||
| S->pCoeffs = pCoeffs; | ||||
| /* Clear state buffer and size is always blockSize + numTaps - 1 */ | ||||
| memset(pState, 0, (numTaps + (blockSize - 1u)) * sizeof(q15_t)); | ||||
| /* Assign post Shift value applied to coefficients */ | ||||
| S->postShift = postShift; | ||||
| /* Assign state pointer */ | ||||
| S->pState = pState; | ||||
| /* Assign Step size value */ | ||||
| S->mu = mu; | ||||
| /* Initialize reciprocal pointer table */ | ||||
| S->recipTable = armRecipTableQ15; | ||||
| /* Initialise Energy to zero */ | ||||
| S->energy = 0; | ||||
| /* Initialise x0 to zero */ | ||||
| S->x0 = 0; | ||||
| } | ||||
| /** | ||||
| * @} end of LMS_NORM group | ||||
| */ | ||||