Demodulates a double sideband (DSB) amplitudemodulated signal.
The modulated complex baseband timedomain data for demodulation.
The trigger (start) time of the Y array.
Default: 0.0
Time interval between data points in the Y array.
Default: 1.0
The complexvalued timedomain data array. The real and imaginary parts of this complex data array correspond to the inphase (I) and quadraturephase (Q) data, respectively.
The expected modulation index of the AM demodulated waveform parameter. This value is used to scale the AM demodulated waveform parameter.
Default: 1.0
Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.
Default: no error
A Boolean that determines whether the carrier has been suppressed in the incoming AMDSBmodulated waveform.
Demodulation proceeds according to one of the following methods, depending on whether suppressed carrier? is set to TRUE or FALSE.
TRUE  The incoming baseband AMDSBSC modulated signal $r\left(t\right)$ can be expressed as the following equations: $r\left(t\right)={s}_{DSBSC}\left(t\right){e}^{j\phi \left(t\right)}$ where ${s}_{DSBSC}\left(t\right)$ is an AMDSBSC modulated waveform, and $\phi \left(t\right)$ is any timevarying phase ambiguity. The node squares the signal $r\left(t\right)$ when computing the phase estimate of $\phi \left(t\right)$. This squaring operation removes the 180 degrees phase ambiguity relative to the sign of $m\left(t\right)$. The computed phase estimate is used to generate a complex tone that is added back to the input signal $r\left(t\right)$ to generate the equivalent DSB signal with carrier and unity modulation index. Thereon, envelope detection is performed for computing the AM demodulated waveform output $\stackrel{^}{m}\left(t\right)$. The recovered message signal $\stackrel{^}{m}\left(t\right)$ can be obtained from the following relationships:
$r\left(t\right)={S}_{DSBSC}\left(t\right){e}^{j\varphi \left(t\right)}$
$\stackrel{^}{\varphi}\left(t\right)=0.5*\mathrm{arg}\left({r}^{2}\right(t\left)\right)$
${r}_{DSB}\left(t\right)=r\left(t\right)+{e}^{j*\stackrel{^}{\varphi}\left(t\right)}={s}_{DSBSC}\left(t\right){e}^{j\varphi \left(t\right)}+{e}^{j*\stackrel{^}{\varphi}\text{\hspace{0.17em}}t}$
$\stackrel{^}{m}\left(t\right)=\frac{\left{r}_{DSB}\right(t\left)\right}{\langle \left{r}_{DSB}\right(t\left)\right\rangle}1$

FALSE  The incoming baseband AMDSB modulated signal $r\left(t\right)$ can be expressed by the following equations: $r\left(t\right)={s}_{DSB}\left(t\right){e}^{j\phi \left(t\right)}$ where ${s}_{DSB}\left(t\right)$ is a DSB modulated waveform and $\phi \left(t\right)$ is any timevarying phase ambiguity. AMDSB demodulation involves performing envelope detection. The AM demodulated waveform (t) is given by the following equation:
$\stackrel{^}{m}\left(t\right)=\frac{1}{k}*[\frac{\leftr\right(t\left)\right}{\langle \leftr\right(t\left)\right\rangle}1]$
where $k$ represents the modulation index. 
Default: FALSE
The recovered message signal.
Wire the AM demodulated waveform parameter to any LabVIEW waveform measurement node for further analysis. If the information signal is a single tone (normalized) and modulation index is set to 1.0 with suppressed carrier? set to FALSE, the peak amplitude value of the AMdemodulated waveform represents the true modulation index of the incoming AMmodulated waveform.
The mean zerotopeak amplitude, in volts, of the IF carrier wave.
Error information. The node produces this output according to standard error behavior.
Demodulation using this node depends on whether suppressed carrier? is set to TRUE or FALSE.
Installed By: LabVIEW Communications System Design Suite (introduced in 1.0)
Where This Node Can Run:
Desktop OS: Windows
FPGA: Not supported
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