(8.D.2.3) ComplexModulate
Overview
This module accepts a real or complex input and generates a complex
Discussion
This module multiplies the input by the complex exponential exp(-j*2*pi*modBin*n/K) where modBin is an inspector parameter, K is the size of the input buffer (the FFT size) and n = 0:1:(K-1) is the sample number in the block. The only tunable parameter is modBin and K is taken from the wire size.
This module is usually used as part of frequency domain processing. The module effectively shifts the frequency spectrum right by 2*pi*modBin/K radians/sample. Alternatively, you can think of the modules as shifting by modBin FFT bins.
modBin is a floating-point value and can take on any real value including non-integer values. By default modBin = 0.25. The module supports real and complex inputs and always generates a complex output.
Type Definition
typedef struct _ModuleComplexModulate
{
ModuleInstanceDescriptor instance; // Common Audio Weaver module instance structure
FLOAT32 modBin; // Omega of modulation coefficient equation.
FLOAT32* modCoeffs; // Modulation coefficient array
} ModuleComplexModulateClass;
Variables
Properties
Name | Type | Usage | isHidden | Default value | Range | Units |
modBin | float | parameter | 0 | 0.25 | Unrestricted | Â |
modCoeffs | float* | state | 1 | [32 x 1] | Unrestricted | Â |
Pins
Input Pins
Name: in
Description: Real or complex input
Data type: float
Channel range: 1
Block size range: Unrestricted
Sample rate range: Unrestricted
Complex support: Real and Complex
Output Pins
Name: cmplx
Description: Complex result
Data type: float
MATLAB Usage
File Name: complex_modulate_module.m
M=complex_modulate_module(NAME)
This module accepts a real or complex input and generates a complex
output by multiplying input with exp(j*2*pi*modBin*n/N)
Arguments:
NAME - name of the module.
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