1 /*-----------------------------------------------------------------------------
2 * Copyright (C) 2010-2013 ARM Limited. All rights reserved.
4 * $Date: 17. January 2013
7 * Project: CMSIS DSP Library
8 * Title: arm_lms_norm_init_f32.c
10 * Description: Floating-point NLMS filter initialization function.
12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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44 * @ingroup groupFilters
48 * @addtogroup LMS_NORM
53 * @brief Initialization function for floating-point normalized LMS filter.
54 * @param[in] *S points to an instance of the floating-point LMS filter structure.
55 * @param[in] numTaps number of filter coefficients.
56 * @param[in] *pCoeffs points to coefficient buffer.
57 * @param[in] *pState points to state buffer.
58 * @param[in] mu step size that controls filter coefficient updates.
59 * @param[in] blockSize number of samples to process.
63 * <code>pCoeffs</code> points to the array of filter coefficients stored in time reversed order:
65 * {b[numTaps-1], b[numTaps-2], b[N-2], ..., b[1], b[0]}
67 * The initial filter coefficients serve as a starting point for the adaptive filter.
68 * <code>pState</code> points to an array of length <code>numTaps+blockSize-1</code> samples,
69 * where <code>blockSize</code> is the number of input samples processed by each call to <code>arm_lms_norm_f32()</code>.
72 void arm_lms_norm_init_f32(
73 arm_lms_norm_instance_f32
* S
,
80 /* Assign filter taps */
83 /* Assign coefficient pointer */
86 /* Clear state buffer and size is always blockSize + numTaps - 1 */
87 memset(pState
, 0, (numTaps
+ (blockSize
- 1u)) * sizeof(float32_t
));
89 /* Assign state pointer */
92 /* Assign Step size value */
95 /* Initialise Energy to zero */
98 /* Initialise x0 to zero */
104 * @} end of LMS_NORM group