modulates an optical signal depending on electrical signal
Keywords
electrical, optical, unidirectional
Ports
| Name | Type |
|---|---|
| input | Optical Signal |
| modulation | Electrical Signal |
| output | Optical Signal |
Properties
General Properties
| Name | Default value | Default unit | Range |
|---|---|---|---|
|
name Defines the name of the element. |
Optical Amplitude Modulator | - | - |
|
annotate Defines whether or not to display annotations on the schematic editor. |
true | - | [true, false] |
|
enabled Defines whether or not the element is enabled. |
true | - | [true, false] |
|
type Defines the element unique type (read only). |
Optical Amplitude Modulator | - | - |
|
description A brief description of the elements functionality. |
modulates an optical signal depending on electrical signal | - | - |
|
prefix Defines the element name prefix. |
AM | - | - |
|
model Defines the element model name. |
- | - | - |
|
library Defines the element location or source in the library (custom or design kit). |
- | - | - |
|
local path Defines the local path or working folder $LOCAL for the element. |
- | - | - |
|
url An optional URL address pointing to the element online help. |
- | - | - |
Standard Properties
| Name | Default value | Default unit | Range |
|---|---|---|---|
|
modulation index Defines the modulation index of the modulator. |
1 | - | [0, 1] |
Waveguide Properties
| Name | Default value | Default unit | Range |
|---|---|---|---|
|
modes List of optical mode labels supported by the element. |
TE,TM | - | - |
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Implementation Details
The amplitude modulator (AM) modulates the amplitude of the carrier (optical signal) in proportion to the strength of the electrical signal. Please see the example file AM.icp for more information. The system in the example file demonstrates the working principle of the AM. The second figure is the parameter setting window of the AM.
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The key character of AM is the modulation index. The modulation index is defined by how much the modulated variable varies around its un-modulated level, \( h = \frac{M}{P} \), where M is the modulation power and P is the carrier power. The figure below shows modulated signals when the modulation index is 1 and 0.5.
The modulation index is calculated by the equation
$$ h = \frac{M}{P_{carrier}} = \frac{M_{max} - M_{min}}{P_{carrier}} $$