RFIEEE 802.15.6 WBAN MAC Layer Basics
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This page describes the basics of the IEEE 802.15.6 MAC layer, focusing on MAC layer frames as they relate to different WBAN PHY layers. As per the IEEE 802.15.6 standard, nodes are organized into one or two-hop star WBANs.
A single coordinator, often referred to as a hub, controls the entire operation of each WBAN network. Essentially, a WBAN is composed of one hub and multiple nodes.
In a one-hop star BAN, frame exchanges happen directly between the nodes and the hub. Conversely, in a two-hop extended star BAN, the hub and a node exchange frames through a relay-capable node.
Figure: WBAN MAC Layer Frame
The figure above illustrates a MAC frame, which is composed of a fixed-length MAC header, a variable-size MAC frame body, and a fixed-size FCS (Frame Check Sequence).
The MAC header, as shown, includes the frame control field, recipient ID, sender ID, and BAN ID. The figure also highlights the various fields contained within the frame control part.
Similar to other standards, IEEE 802.15.6 WBAN defines type and subtype fields. The type field indicates the type of the current frame, while the subtype field specifies the subtype.
WBAN Frames are categorized into management, control, and data frames.
The IEEE 802.15.6 WBAN supports the following communication modes:
- Beacon Mode with Superframe Boundaries
- Nonbeacon Mode with Superframe Boundaries
- Nonbeacon Mode without Superframe Boundaries
WBAN also supports the following access mechanisms:
- Random Access Mechanism: This covers slotted ALOHA and CSMA/CD, depending on the PHY mode (NB, HBC, and UWB).
- Improvised and Unscheduled Access Mechanism
- Scheduled and Scheduled Polling Access Mechanisms
