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diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_mean_q15.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_mean_q15.c
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+/* ----------------------------------------------------------------------
+ * Project: CMSIS DSP Library
+ * Title: arm_mean_q15.c
+ * Description: Mean value of a Q15 vector
+ *
+ * $Date: 18. March 2019
+ * $Revision: V1.6.0
+ *
+ * Target Processor: Cortex-M cores
+ * -------------------------------------------------------------------- */
+/*
+ * Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the License); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an AS IS BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "arm_math.h"
+
+/**
+ @ingroup groupStats
+ */
+
+/**
+ @addtogroup mean
+ @{
+ */
+
+/**
+ @brief Mean value of a Q15 vector.
+ @param[in] pSrc points to the input vector
+ @param[in] blockSize number of samples in input vector
+ @param[out] pResult mean value returned here
+ @return none
+
+ @par Scaling and Overflow Behavior
+ The function is implemented using a 32-bit internal accumulator.
+ The input is represented in 1.15 format and is accumulated in a 32-bit
+ accumulator in 17.15 format.
+ There is no risk of internal overflow with this approach, and the
+ full precision of intermediate result is preserved.
+ Finally, the accumulator is truncated to yield a result of 1.15 format.
+ */
+
+void arm_mean_q15(
+ const q15_t * pSrc,
+ uint32_t blockSize,
+ q15_t * pResult)
+{
+ uint32_t blkCnt; /* Loop counter */
+ q31_t sum = 0; /* Temporary result storage */
+
+#if defined (ARM_MATH_LOOPUNROLL)
+ q31_t in;
+#endif
+
+#if defined (ARM_MATH_LOOPUNROLL)
+
+ /* Loop unrolling: Compute 4 outputs at a time */
+ blkCnt = blockSize >> 2U;
+
+ while (blkCnt > 0U)
+ {
+ /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+ in = read_q15x2_ia ((q15_t **) &pSrc);
+ sum += ((in << 16U) >> 16U);
+ sum += (in >> 16U);
+
+ in = read_q15x2_ia ((q15_t **) &pSrc);
+ sum += ((in << 16U) >> 16U);
+ sum += (in >> 16U);
+
+ /* Decrement the loop counter */
+ blkCnt--;
+ }
+
+ /* Loop unrolling: Compute remaining outputs */
+ blkCnt = blockSize % 0x4U;
+
+#else
+
+ /* Initialize blkCnt with number of samples */
+ blkCnt = blockSize;
+
+#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
+
+ while (blkCnt > 0U)
+ {
+ /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
+ sum += *pSrc++;
+
+ /* Decrement loop counter */
+ blkCnt--;
+ }
+
+ /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */
+ /* Store result to destination */
+ *pResult = (q15_t) (sum / (int32_t) blockSize);
+}
+
+/**
+ @} end of mean group
+ */