CMSIS-DSP  Version 1.4.7
CMSIS DSP Software Library
 All Data Structures Files Functions Variables Typedefs Enumerations Enumerator Macros Groups Pages
Complex-by-Real Multiplication

Functions

void arm_cmplx_mult_real_f32 (float32_t *pSrcCmplx, float32_t *pSrcReal, float32_t *pCmplxDst, uint32_t numSamples)
 Floating-point complex-by-real multiplication.
 
void arm_cmplx_mult_real_q15 (q15_t *pSrcCmplx, q15_t *pSrcReal, q15_t *pCmplxDst, uint32_t numSamples)
 Q15 complex-by-real multiplication.
 
void arm_cmplx_mult_real_q31 (q31_t *pSrcCmplx, q31_t *pSrcReal, q31_t *pCmplxDst, uint32_t numSamples)
 Q31 complex-by-real multiplication.
 

Description

Multiplies a complex vector by a real 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 while the real array has a total of numSamples real values.

The underlying algorithm is used:

        
for(n=0; n<numSamples; n++) {        
    pCmplxDst[(2*n)+0] = pSrcCmplx[(2*n)+0] * pSrcReal[n];        
    pCmplxDst[(2*n)+1] = pSrcCmplx[(2*n)+1] * pSrcReal[n];        
}        

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

Function Documentation

void arm_cmplx_mult_real_f32 ( float32_t pSrcCmplx,
float32_t pSrcReal,
float32_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]*pSrcCmplxpoints to the complex input vector
[in]*pSrcRealpoints to the real input vector
[out]*pCmplxDstpoints to the complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none.
void arm_cmplx_mult_real_q15 ( q15_t pSrcCmplx,
q15_t pSrcReal,
q15_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]*pSrcCmplxpoints to the complex input vector
[in]*pSrcRealpoints to the real input vector
[out]*pCmplxDstpoints to the complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none.

Scaling and Overflow Behavior:

The function uses saturating arithmetic. Results outside of the allowable Q15 range [0x8000 0x7FFF] will be saturated.

References __SIMD32.

void arm_cmplx_mult_real_q31 ( q31_t pSrcCmplx,
q31_t pSrcReal,
q31_t pCmplxDst,
uint32_t  numSamples 
)
Parameters
[in]*pSrcCmplxpoints to the complex input vector
[in]*pSrcRealpoints to the real input vector
[out]*pCmplxDstpoints to the complex output vector
[in]numSamplesnumber of samples in each vector
Returns
none.

Scaling and Overflow Behavior:

The function uses saturating arithmetic. Results outside of the allowable Q31 range[0x80000000 0x7FFFFFFF] will be saturated.

References clip_q63_to_q31().