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diff --git a/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c b/apps/mathlib/CMSIS/DSP_Lib/Source/TransformFunctions/arm_cfft_radix2_q31.c
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+/* ----------------------------------------------------------------------
+* Copyright (C) 2010 ARM Limited. All rights reserved.
+*
+* $Date: 15. February 2012
+* $Revision: V1.1.0
+*
+* Project: CMSIS DSP Library
+* Title: arm_cfft_radix2_q31.c
+*
+* Description: Radix-2 Decimation in Frequency CFFT & CIFFT Fixed point processing function
+*
+*
+* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
+*
+* Version 1.1.0 2012/02/15
+* Updated with more optimizations, bug fixes and minor API changes.
+*
+* Version 0.0.3 2010/03/10
+* Initial version
+* -------------------------------------------------------------------- */
+
+#include "arm_math.h"
+
+/**
+ * @ingroup groupTransforms
+ */
+
+/**
+ * @defgroup Radix2_CFFT_CIFFT Radix-2 Complex FFT Functions
+ *
+ * \par
+ * Complex Fast Fourier Transform(CFFT) and Complex Inverse Fast Fourier Transform(CIFFT) is an efficient algorithm to compute Discrete Fourier Transform(DFT) and Inverse Discrete Fourier Transform(IDFT).
+ * Computational complexity of CFFT reduces drastically when compared to DFT.
+ */
+
+
+/**
+ * @addtogroup Radix2_CFFT_CIFFT
+ * @{
+ */
+
+/**
+ * @details
+ * @brief Processing function for the fixed-point CFFT/CIFFT.
+ * @param[in] *S points to an instance of the fixed-point CFFT/CIFFT structure.
+ * @param[in, out] *pSrc points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place.
+ * @return none.
+ */
+
+void arm_cfft_radix2_q31(
+ const arm_cfft_radix2_instance_q31 * S,
+ q31_t * pSrc)
+{
+
+ if(S->ifftFlag == 1u)
+ {
+ arm_radix2_butterfly_inverse_q31(pSrc, S->fftLen,
+ S->pTwiddle, S->twidCoefModifier);
+ }
+ else
+ {
+ arm_radix2_butterfly_q31(pSrc, S->fftLen,
+ S->pTwiddle, S->twidCoefModifier);
+ }
+
+ arm_bitreversal_q31(pSrc, S->fftLen, S->bitRevFactor, S->pBitRevTable);
+}
+
+/**
+ * @} end of Radix2_CFFT_CIFFT group
+ */
+
+void arm_radix2_butterfly_q31(
+ q31_t * pSrc,
+ uint32_t fftLen,
+ q31_t * pCoef,
+ uint16_t twidCoefModifier)
+{
+
+ int i, j, k, l;
+ int n1, n2, ia;
+ q31_t xt, yt, cosVal, sinVal;
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
+
+ pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) +
+ ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+
+ pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) -
+ ((int32_t) (((q63_t) xt * sinVal) >> 32)));
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
+
+ pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) +
+ ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+
+ pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) -
+ ((int32_t) (((q63_t) xt * sinVal) >> 32)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = 0; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ i += n1;
+ l = i + n2;
+
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ } // butterfly loop end
+
+}
+
+
+void arm_radix2_butterfly_inverse_q31(
+ q31_t * pSrc,
+ uint32_t fftLen,
+ q31_t * pCoef,
+ uint16_t twidCoefModifier)
+{
+
+ int i, j, k, l;
+ int n1, n2, ia;
+ q31_t xt, yt, cosVal, sinVal;
+
+ //N = fftLen;
+ n2 = fftLen;
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (i = 0; i < n2; i++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ l = i + n2;
+ xt = (pSrc[2 * i] >> 2u) - (pSrc[2 * l] >> 2u);
+ pSrc[2 * i] = ((pSrc[2 * i] >> 2u) + (pSrc[2 * l] >> 2u)) >> 1u;
+
+ yt = (pSrc[2 * i + 1] >> 2u) - (pSrc[2 * l + 1] >> 2u);
+ pSrc[2 * i + 1] =
+ ((pSrc[2 * l + 1] >> 2u) + (pSrc[2 * i + 1] >> 2u)) >> 1u;
+
+ pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) -
+ ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+
+ pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) +
+ ((int32_t) (((q63_t) xt * sinVal) >> 32)));
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+
+ // loop for stage
+ for (k = fftLen / 2; k > 2; k = k >> 1)
+ {
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ // loop for groups
+ for (j = 0; j < n2; j++)
+ {
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = j; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]) >> 1u;
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]) >> 1u;
+
+ pSrc[2u * l] = (((int32_t) (((q63_t) xt * cosVal) >> 32)) -
+ ((int32_t) (((q63_t) yt * sinVal) >> 32)));
+
+ pSrc[2u * l + 1u] = (((int32_t) (((q63_t) yt * cosVal) >> 32)) +
+ ((int32_t) (((q63_t) xt * sinVal) >> 32)));
+
+ } // butterfly loop end
+
+ } // groups loop end
+
+ twidCoefModifier = twidCoefModifier << 1u;
+ } // stages loop end
+
+ n1 = n2;
+ n2 = n2 >> 1;
+ ia = 0;
+
+ cosVal = pCoef[ia * 2];
+ sinVal = pCoef[(ia * 2) + 1];
+ ia = ia + twidCoefModifier;
+
+ // loop for butterfly
+ for (i = 0; i < fftLen; i += n1)
+ {
+ l = i + n2;
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ i += n1;
+ l = i + n2;
+
+ xt = pSrc[2 * i] - pSrc[2 * l];
+ pSrc[2 * i] = (pSrc[2 * i] + pSrc[2 * l]);
+
+ yt = pSrc[2 * i + 1] - pSrc[2 * l + 1];
+ pSrc[2 * i + 1] = (pSrc[2 * l + 1] + pSrc[2 * i + 1]);
+
+ pSrc[2u * l] = xt;
+
+ pSrc[2u * l + 1u] = yt;
+
+ } // butterfly loop end
+
+}
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