Automatic gain control
Keywords
electrical, unidirectional
Ports
| Name | Type |
|---|---|
| input | Electrical Signal |
| output | Electrical Signal |
Properties
General Properties
| Name | Default value | Default unit | Range |
|---|---|---|---|
|
name Defines the name of the element. |
Automatic Gain Control | - | - |
|
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). |
Automatic Gain Control | - | - |
|
description A brief description of the elements functionality. |
Automatic gain control | - | - |
|
prefix Defines the element name prefix. |
AGC | - | - |
|
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 |
|---|---|---|---|
|
output target The target output parameter (power or amplitude range). |
range | - | [power, range |
|
output power The average output power. |
1 | W | [0, +∞) |
|
maximum gain The maximum gain applied to the input signal. |
6 | dB | [0, +∞) |
|
minimum amplitude The target output minimum amplitude. |
0 | a.u. | (-∞, +∞) |
|
maximum amplitude The target output maximum amplitude. |
1 | a.u. | (-∞, +∞) |
|
start time Time instant to start the signal analysis. |
0 | s | [0, +∞) |
|
stop time Time instant to stop the signal analysis. |
256/%sample rate% | s | [0, +∞) |
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Implementation Details
The Automatic Gain Control (AGC) element provides a stable output signal level (amplitude or power), despite of the input signal amplitude/power level. It can dynamically adjust the input-to-output gain so that the output signal is always in the specified range. For this element, user have two options for the "output target": "range" and "power". User need to provide the "maximum amplitude" and "minimum amplitude" for the "range" option and "output power" and "maximum gain" for the "power" option. Start and stop operation time for the AGC is always required.
Following is the circuit in the example file automatic_gain_control.icp:
The above circuit uses the "range" option for the AGC element. The specified range for the AGC is [-2, 1] and the signal waveform before and after the AGC is shown below (for time period 0 - 2 ns). User can see that the output signal level is as defined in the range [-2 ,1].
The second circuit uses the "power" option for the AGC element. For this option, user need to provide both maximum allowed "output power" level and the "maximum gain", and the output signal will follow whichever reaches first. In the example file, the "output power" is set to 100 W and the "maximum gain" is set to 60 dB. In this case, the "output power" limit is the first one to reach and the signal before and after the AGC is shown below (for time period 0 - 2 ns):