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WirelessHART, The Leading Technology for Industrial Wireless Networked Control Systems
Published in Tran Duc Chung, Rosdiazli Ibrahim, Vijanth Sagayan Asirvadam, Nordin Saad, Sabo Miya Hassan, TM, 2017
Tran Duc Chung, Rosdiazli Ibrahim, Vijanth Sagayan Asirvadam, Nordin Saad, Sabo Miya Hassan
WirelessHART supports time division multiple access (TDMA), frequency hopping spread spectrum (FHSS) and direct sequence spread spectrum (DSSS) to provide fully-redundant mesh routing and offers very high reliability for data transmission (up to 99.999%). The TDMA mechanism (see Figure 2.2) is described as follows [10]. Given a time slot, both wireless source and destination must be active during this transmission time slot. First, the transmission starts, and the message is sent from the source to the destination. When the destination receives the message, if required, it needs to send back to the source an acknowledgment message stating whether the message has been received successfully or not. This is to ensure reliable communication in the network. The offset time before the transmission starts is to make sure the destination has sufficient time to start up its initialization operation (e.g., wake up from sleep) and actively listen to the message sent from the source. Similarly, before the acknowledgment message is sent, there is a buffer time for the source to change its state to listening mode (being a destination). To guarantee successful communication, both source and destination need to know when the time slot for communication between them starts. Thus, a network-wide time synchronization mechanism is applied to all nodes in the network on a periodic basis. A superframe is a set of several continuous time slots for communication between one pair of the network devices. Often, it is used to improve communication reliability in the network.
Quality of Service MAC for Wireless Sensor Networks
Published in Shafiullah Khan, Al-Sakib Khan Pathan, Nabil Ali Alrajeh, Wireless Sensor Networks, 2016
Bilal Muhammad Khan, Rabia Bilal
The major drawback of this protocol is the length of superframe. If the superframe is too short, then all the neighbor nodes will not be visible to the node. Another drawback will be in terms of network load and number of nodes. If the network load is low but the number of nodes in the neighborhood is high, the node will be awake on every set schedule just to find no data transfer. The protocol incurs high overheads and can consume energy.
IEEE 802.16m Radio Access Technology
Published in Jerry D. Gibson, Mobile Communications Handbook, 2017
In IEEE 802.16m, a superframe is defined as a collection of consecutive equally sized radio frames whose beginning is marked with a superframe header. The superframe header carries short-term and long-term system configuration information.
Mitigating the Coexistence Technique in Wireless Body Area Networks By Using Superframe Interleaving
Published in IETE Journal of Research, 2022
Samira Kanwal, Junaid Rashid, Jungeun Kim, Sapna Juneja, Gaurav Dhiman, Amir Hussain
Figure 11 shows the packet delivery ratio of extended IEEE 802.15.6 and dynamic IEEE 802.15.6. PDR is above 50% in both schemes, but in dynamic extended, it is quite higher than the extended IEEE 802.15.6. The PDR is higher in dynamic IEEE 802.15.6 because it is traffic-aware and adjusts the BANs Superframe according to traffic. The cluster head calculates the traffic requirement on its HUB and assigns new Superframe sizes to other BANs in the communication channel. Therefore, results in terms of PDR are better as compared to extended IEEE 802.15.6.