An emitter/receiver device is attached to a zone entity (see creating zones). 

The emitter sends its signal in the direction of, and with the same "shape" as its parent zone. For example, infra-red emission typically uses a cone-type zone (emission bounded by a cone), and RF (radio frequency) emission is usually a sphere-shaped zone (omni-directional). 

A receiver can accept messages that arrive in its zone. In this case, only the zone's shape matters, not the size of the zone. 

Reception is only possible if the emission range, in the direction of the receiver, is greater than or equal to the distance between the emitter and the receiver (with respect to the center of the parent zone). 

If this is the case, zones still need to be compatible in order to exchange messages, that is the segment S which passes through the center of both zones: 

Emitter zone /Receiver zone	Compatibility
Sphere / Sphere	Emission in all directions and reception in all directions: S simply has to reach the center of the receiver zone for transmission to succeed.
Sphere / Cone	Reception possible if S passes through the receiver cone without touching its edges.
Sphere / Box	Same operation as Sphere / Sphere
Cone / Sphere	Reception possible if S passes through the emitter's cone without touching its edges.
Cone / Cone	Reception possible if S passes through the interior of both cones without touching the edges.
Cone / Box	Same operation as Cone / Sphere
Box / Sphere	(under development)
Box / Cone	(under development)
Box / Box	Same operation as Box / Sphere

Filters and standards (communication media) are applied to devices. This includes wireless support (802.11, serial, etc.) and support for light waves (i.e. infrared) and sound waves. The various media and standards depend on device configuration.

Step	Description
Create the zone(s) that will contain the emitter/receiver: In the screen shot on the right, we have attached these zones to physical boxes in order to be able to move them around while simulation is running (you may not select zones during simulation). These are 3-D objects that can be attached to any physical object. You will find zones on the Add > 3D tab
Configuring the zone's shape  Select the zone and display its properties. Choose the zone style and fill in the various parameters. Visual Size has no effect on simulation.
Attaching an emitter/receiver device: Make sure that the zone to modify is still selected. Select the "External Plugins Devices" panel and click on "Choose Device". A dialog box will show the devices that can be attached to the zone. Choose an emitter/receiver. Return to the "Modify" panel, select the device and assign it a name in the "Mount as" field. Double-click on the device to edit its local properties.
In MODA programming, emitters/receivers are accessible via the DeviceEmitterReceiver class. The device's full path in this example, starting at PHX "/" is zone3/myemitter.

As zone is considered as a rendered entity, it is therefore possible to attach it to a physical entity so that it follows the movement of the entity (see Attaching to a physical entity).

A given zone may contain several emitters/receivers.

Emitters/receivers