Complex Conjugate

Functions
void	arm_cmplx_conj_f16 (const float16_t *pSrc, float16_t *pDst, uint32_t numSamples)
	Floating-point complex conjugate.
void	arm_cmplx_conj_f32 (const float32_t *pSrc, float32_t *pDst, uint32_t numSamples)
	Floating-point complex conjugate.
void	arm_cmplx_conj_q15 (const q15_t *pSrc, q15_t *pDst, uint32_t numSamples)
	Q15 complex conjugate.
void	arm_cmplx_conj_q31 (const q31_t *pSrc, q31_t *pDst, uint32_t numSamples)
	Q31 complex conjugate.

Description

Conjugates the elements of a complex data vector.

The pSrc points to the source data and pDst points to the destination data where the result should be written. numSamples specifies the number of complex samples and the data in each array is stored in an interleaved fashion (real, imag, real, imag, ...). Each array has a total of 2*numSamples values.

The underlying algorithm is used:

for (n = 0; n < numSamples; n++) {
    pDst[(2*n)  ] =  pSrc[(2*n)  ];    // real part
    pDst[(2*n)+1] = -pSrc[(2*n)+1];    // imag part
}

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

Function Documentation

arm_cmplx_conj_f16()

void arm_cmplx_conj_f16	(	const float16_t *	pSrc,
		float16_t *	pDst,
		uint32_t	numSamples
	)

Floating-point complex conjugate.

Parameters

[in]	pSrc	points to the input vector
[out]	pDst	points to the output vector
[in]	numSamples	number of samples in each vector

arm_cmplx_conj_f32()

void arm_cmplx_conj_f32	(	const float32_t *	pSrc,
		float32_t *	pDst,
		uint32_t	numSamples
	)

Floating-point complex conjugate.

Parameters

[in]	pSrc	points to the input vector
[out]	pDst	points to the output vector
[in]	numSamples	number of samples in each vector

arm_cmplx_conj_q15()

void arm_cmplx_conj_q15	(	const q15_t *	pSrc,
		q15_t *	pDst,
		uint32_t	numSamples
	)

Q15 complex conjugate.

Parameters

[in]	pSrc	points to the input vector
[out]	pDst	points to the output vector
[in]	numSamples	number of samples in each vector

Scaling and Overflow Behavior

The function uses saturating arithmetic. The Q15 value -1 (0x8000) is saturated to the maximum allowable positive value 0x7FFF.

arm_cmplx_conj_q31()

void arm_cmplx_conj_q31	(	const q31_t *	pSrc,
		q31_t *	pDst,
		uint32_t	numSamples
	)

Q31 complex conjugate.

Parameters

[in]	pSrc	points to the input vector
[out]	pDst	points to the output vector
[in]	numSamples	number of samples in each vector

Scaling and Overflow Behavior

The function uses saturating arithmetic. The Q31 value -1 (0x80000000) is saturated to the maximum allowable positive value 0x7FFFFFFF.