Scicos Block
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I/Q modulator block

Contents

• I/Q modulator block
  • Palette
  • Description
  • Basic blocks equivalent model
  • Dialog box
  • Default properties
  • Interfacing function
  • Computational function
  • See also
  • Authors

Palette

• Communication - Communication palette

Description

This block realizes a complex local oscillator. This block computes :

$$\begin{eqnarray} y_{1}(t) = u_{1}(t)\cos\left(\omega_{o}t\right)-u_{2}(t)\sin\left(\omega_{o}t\right) \end{eqnarray}$$

$$\begin{eqnarray} y_{2}(t) = u_{1}(t)\sin\left(\omega_{o}t\right)+u_{2}(t)\cos\left(\omega_{o}t\right) \end{eqnarray}$$

where u1,u2 are the two regular inputs and y1,y2 the regular outputs. w0 is set with the dialogue parameter 'Vector of carrier frequency'. Typically, it is used to transpose base band symbol components at a given carrier frequency as shown in the following figure :

The activation dates of this block gives the sampling step of the outputs.

Basic blocks equivalent model

Dialog box

• Vector of carrier frequency
  The vector of the free-running frequencies of local oscillators.
  Type 'vec' de taille 1.

Default properties

• always active: no
• direct-feedthrough: yes
• zero-crossing: no
• mode: no
• regular inputs:
  - port 1 : size [1,1] / type 1
  - port 2 : size [1,1] / type 1
  
• regular outputs:
  - port 1 : size [1,1] / type 1
  - port 2 : size [1,1] / type 1
  
• number/sizes of activation inputs: 1
• number/sizes of activation outputs: 0
• continuous-time state: no
• discrete-time state: no
• object discrete-time state: no
• name of computational function: modiq

Interfacing function

• MODNUMCOS/macros/scicos_blocks/Communication/MODIQ_f.sci [view code]

Computational function

• MODNUMCOS/routines/communication/modiq.c (Type 2) [view code]

See also

• DEMODIQ_f - I/Q demodulator block (Scicos Block)

Authors

IRCOM Group Alan Layec