vlcsim.scene.VLed

class vlcsim.scene.VLed(x: float, y: float, z: float, nLedsX: int, nLedsY: int, ledPower: float, theta: float)[source]

Bases: AccessPoint

Visible Light LED (VLed) access point for VLC communication.

VLed represents a LED-based access point that transmits data using visible light. It extends AccessPoint with optical transmission parameters including LED array configuration, optical power, and beam characteristics.

The class automatically calculates derived parameters such as total power and Lambertian emission order based on the LED configuration.

Class Attributes:

numberOfVLeds (int): Counter tracking total number of VLed instances created

Properties:

Inherited from AccessPoint:: x, y, z, position, state, ID, B, sliceTime, slicesInFrame
VLed-specific:: nLedsX (int): Number of LEDs in X direction (rows) nLedsY (int): Number of LEDs in Y direction (columns) ledPower (float): Power per LED in milliwatts theta (float): Semi-angle at half illumination in degrees numberOfLeds (int): Total LEDs in array (read-only) totalPower (float): Total optical power in milliwatts ml (float): Lambertian emission order (read-only)

Example

Creating a VLed access point:

# Create 2x2 LED array at ceiling center
# Position: (5m, 5m, 3m)
# Each LED: 20mW power
# Beam angle: 60 degrees semi-angle
vled = VLed(x=5.0, y=5.0, z=3.0,
           nLedsX=2, nLedsY=2,
           ledPower=20, theta=60)

# Configure TDM parameters
vled.sliceTime = 0.1  # 100ms per slice
vled.slicesInFrame = 10  # 10 slices per frame
vled.B = 5e5  # 500 kHz bandwidth

# Total power is automatically calculated
print(f"Total power: {vled.totalPower}mW")  # 80mW (4 LEDs * 20mW)
print(f"Lambertian order: {vled.ml}")

Note

ID is automatically assigned incrementally starting from 0
Lambertian emission order ml is calculated as -log10(2)/log10(cos(theta))
totalPower equals nLedsX * nLedsY * ledPower
Typical theta values range from 30-70 degrees for indoor VLC

__init__(x: float, y: float, z: float, nLedsX: int, nLedsY: int, ledPower: float, theta: float) → None[source]

Initialize a VLed access point with optical parameters.

Creates a VLed with specified position and LED array configuration. Automatically calculates total power and Lambertian emission order.

Parameters:

x – X-coordinate position in meters
y – Y-coordinate position in meters
z – Z-coordinate position in meters (typically ceiling height)
nLedsX – Number of LEDs in X direction (rows in the array)
nLedsY – Number of LEDs in Y direction (columns in the array)
ledPower – Optical power per LED in milliwatts (mW)
theta – Semi-angle at half illumination in degrees

Example:

# Create 4x4 LED panel at room center ceiling
vled = VLed(x=5.0, y=5.0, z=3.0,
           nLedsX=4, nLedsY=4,
           ledPower=50, theta=60)

Note

Total LEDs = nLedsX * nLedsY
Total power = numberOfLeds * ledPower
Lambertian order ml = -log10(2)/log10(cos(theta))
VLed ID is auto-assigned from numberOfVLeds class counter

Methods

`__init__`(x, y, z, nLedsX, nLedsY, ledPower, ...)	Initialize a VLed access point with optical parameters.
`setBUSY`()	Set this access point to BUSY state.
`setIDLE`()	Set this access point to IDLE state.

Attributes

`B`	Get the bandwidth of this access point.
`ID`	Get the unique identifier of this access point.
`ledPower`	Get the optical power per individual LED.
`ml`	Get the Lambertian emission order.
`nLedsX`	Get the number of LEDs in X direction (rows).
`nLedsY`	Get the number of LEDs in Y direction (columns).
`numberOfLeds`	Get the total number of LEDs in this VLed array.
`numberOfVLeds`
`position`	Get the 3D position vector of this access point.
`sliceTime`	Get the time duration of each TDM slice.
`slicesInFrame`	Get the number of time slices in each TDM frame.
`state`	Get the current operational state of this access point.
`theta`	Get the semi-angle at half illumination.
`totalPower`	Get the total optical power of this VLed array.
`x`	Get the X-coordinate of this access point.
`y`	Get the Y-coordinate of this access point.
`z`	Get the Z-coordinate of this access point.

property B: float

Get the bandwidth of this access point.

Returns:: Bandwidth in Hz (default: 1 MHz)
Return type:: float

property ID: int | None

Get the unique identifier of this access point.

Returns:: Access point ID, None if not yet assigned
Return type:: int or None

property ledPower: float

Get the optical power per individual LED.

Returns:: Power per LED in milliwatts (mW)
Return type:: float

property ml: float

Get the Lambertian emission order.

The Lambertian order characterizes the directionality of the LED emission pattern. Higher values indicate more directional (focused) emission.

The formula is:

\[ml = -\frac{\log_{10} 2}{\log_{10} (\cos(\theta))}\]

Returns:: Lambertian emission order (dimensionless)
Return type:: float

Note

theta=60° → ml ≈ 1 (wide beam)
theta=30° → ml ≈ 3.3 (narrow beam)
Higher ml means more concentrated light at center

property nLedsX: int

Get the number of LEDs in X direction (rows).

Returns:: Number of LED rows in the array
Return type:: int

property nLedsY: int

Get the number of LEDs in Y direction (columns).

Returns:: Number of LED columns in the array
Return type:: int

property numberOfLeds: int

Get the total number of LEDs in this VLed array.

Calculated as nLedsX * nLedsY.

Returns:: Total number of LEDs in the array
Return type:: int

property position: ndarray[Any, dtype[float64]]

Get the 3D position vector of this access point.

Returns:: Position vector [x, y, z] in meters
Return type:: ndarray

setBUSY() → None

Set this access point to BUSY state.

Transitions the access point to BUSY, indicating it is actively serving connections.

setIDLE() → None

Set this access point to IDLE state.

Transitions the access point to IDLE, indicating it is ready to accept new connections.

property sliceTime: float

Get the time duration of each TDM slice.

The slice time determines how long each connection can use the access point in a single time slice.

Returns:: Slice time duration in seconds (default: 0.1s)
Return type:: float

property slicesInFrame: int

Get the number of time slices in each TDM frame.

This determines the frame structure for time-division multiplexing. Total frame duration equals sliceTime * slicesInFrame.

Returns:: Number of slices per frame (default: 10)
Return type:: int

property state: state

Get the current operational state of this access point.

Returns:: Current state, either IDLE or BUSY
Return type:: stateap

stateap(value): alias of state

property theta: float

Get the semi-angle at half illumination.

Theta defines the beam width of the LED. It is the angle from the optical axis at which the luminous intensity drops to half of its maximum value.

Returns:: Semi-angle in degrees
Return type:: float

Note

Typical values for indoor VLC range from 30-70 degrees. Smaller angles create more focused beams with higher intensity at center.

property totalPower: float

Get the total optical power of this VLed array.

Calculated as numberOfLeds * ledPower.

Returns:: Total optical power in milliwatts (mW)
Return type:: float

Example:

vled = VLed(5, 5, 3, nLedsX=4, nLedsY=4, ledPower=50, theta=60)
# totalPower = 4 * 4 * 50 = 800 mW

property x: float

Get the X-coordinate of this access point.

Returns:: X-coordinate in meters
Return type:: float

property y: float

Get the Y-coordinate of this access point.

Returns:: Y-coordinate in meters
Return type:: float

property z: float

Get the Z-coordinate of this access point.

Returns:: Z-coordinate in meters (typically height)
Return type:: float