Functions

Complex-by-Complex Multiplication
[Complex Math Functions]

Functions

void arm_cmplx_mult_cmplx_f32 (float32_t *pSrcA, float32_t *pSrcB, float32_t *pDst, uint32_t numSamples)
void arm_cmplx_mult_cmplx_q31 (q31_t *pSrcA, q31_t *pSrcB, q31_t *pDst, uint32_t numSamples)
void arm_cmplx_mult_cmplx_q15 (q15_t *pSrcA, q15_t *pSrcB, q15_t *pDst, uint32_t numSamples)

Detailed Description

Multiplies a complex vector by another complex vector and generates a complex result. The data in the complex arrays is stored in an interleaved fashion (real, imag, real, imag, ...). The parameter numSamples represents the number of complex samples processed. The complex arrays have a total of 2*numSamples real values.

The underlying algorithm is used:

   
 for(n=0; n<numSamples; n++) {   
     pDst[(2*n)+0] = pSrcA[(2*n)+0] * pSrcB[(2*n)+0] - pSrcA[(2*n)+1] * pSrcB[(2*n)+1];   
     pDst[(2*n)+1] = pSrcA[(2*n)+0] * pSrcB[(2*n)+1] + pSrcA[(2*n)+1] * pSrcB[(2*n)+0];   
 }   
 

There are separate functions for floating-point, Q15, and Q31 data types.


Function Documentation

void arm_cmplx_mult_cmplx_f32 ( float32_t pSrcA,
float32_t pSrcB,
float32_t pDst,
uint32_t  numSamples 
)

Floating-point complex-by-complex multiplication.

Parameters:
[in]*pSrcApoints to the first input vector
[in]*pSrcBpoints to the second input vector
[out]*pDstpoints to the output vector
[in]numSamplesnumber of complex samples in each vector
Returns:
none.
Examples:
arm_convolution_example_f32.c.

Definition at line 73 of file arm_cmplx_mult_cmplx_f32.c.

void arm_cmplx_mult_cmplx_q31 ( q31_t pSrcA,
q31_t pSrcB,
q31_t pDst,
uint32_t  numSamples 
)

Q31 complex-by-complex multiplication.

Parameters:
[in]*pSrcApoints to the first input vector
[in]*pSrcBpoints to the second input vector
[out]*pDstpoints to the output vector
[in]numSamplesnumber of complex samples in each vector
Returns:
none.

Scaling and Overflow Behavior:

The function implements 1.31 by 1.31 multiplications and finally output is converted into 3.29 format. Input down scaling is not required.

Definition at line 56 of file arm_cmplx_mult_cmplx_q31.c.

void arm_cmplx_mult_cmplx_q15 ( q15_t pSrcA,
q15_t pSrcB,
q15_t pDst,
uint32_t  numSamples 
)

Q15 complex-by-complex multiplication.

Parameters:
[in]*pSrcApoints to the first input vector
[in]*pSrcBpoints to the second input vector
[out]*pDstpoints to the output vector
[in]numSamplesnumber of complex samples in each vector
Returns:
none.

Scaling and Overflow Behavior:

The function implements 1.15 by 1.15 multiplications and finally output is converted into 3.13 format.

Definition at line 54 of file arm_cmplx_mult_cmplx_q15.c.

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