WIRELESS SENSOR NETWORK WITH ENERGY EFFICIENT PROTOCOLS

• US 20130128786A1
• Filed: 11/23/2011
• Published: 05/23/2013
• Est. Priority Date: 11/23/2011
• Status: Active Grant

• Current Assignee: King Abdul AZIZ City For Science and Technology, King Fahd University Of Petroleum And Minerals
• Original Assignee: King Fahd University Of Petroleum And Minerals
• Inventors: ZUMMO, SALAM A., SULTAN, FAROOQ, AL-ABSI, MUNIR A. KULAIB, SHAFI, AHMAR
• Granted Patent: US 8,547,982 B2
• Time in Patent Office: Days
• US Class Current: 370/311
• CPC Class Codes: H04W 52/0238 where the received signal is an unwanted signal, e.g. interference or idle signal
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

The wireless sensor network with energy efficient protocols includes a network of external sensors in communication with a data sink. The network utilizes an algorithm integrating a modified S-MAC (an algorithm for medium access control) protocol for decreasing energy usage in operating the node and associated sensors. A routing protocol is further integrated into the algorithm, the routing protocol being based upon cluster head rotation.

Claims

1. A wireless sensor network with energy efficient protocols, comprising:

a plurality of wireless nodes;

means for forming at least one fixed cluster from the plurality of wireless nodes, the at least one fixed cluster having a cluster head and at least one member node in operable communication with the cluster head;

a sink node; and

means for establishing wireless communication between the sink node and the at least one fixed cluster;

wherein the sink node communicates with the cluster head to obtain sensor data reported by the at least one member node.

2. The wireless sensor network according to claim 1, further comprising:

a single master clock in operable communication with said sink node; and

means for unitarily scheduling all said nodes of the wireless sensor network based on the single master clock.

3. The wireless sensor network according to claim 2, further comprising means for periodically swapping roles between said cluster head and said at least one member node in a non-random manner, wherein said at least one member node becomes said cluster head and said cluster head becomes said at least one member node.

4. The wireless sensor network according to claim 3, further comprising means for forming a logical network tree, said at least one fixed cluster having a tree depth based on a signal strength of a beacon sent from said sink node to said at least one fixed cluster.

5. The wireless sensor network according to claim 4, wherein said means for establishing wireless communication between said sink node and said at least one fixed cluster further comprises means for assuring said cluster head transmits a flow of data directed unidirectionally up said logical network tree in a direction towards and ultimately destined for said sink node.

6. The wireless sensor network according to claim 5, wherein said cluster head has a communications routing table, the network further comprising means for updating the communications routing table.

7. The wireless sensor network according to claim 6, further comprising means for node sleep schedule synchronization based on the beacon sent from said sink node to said at least one fixed cluster.

8. The wireless sensor network according to claim 7, further comprising means for programming transmission power to a lowest setting for communications between said at least one member node and said cluster head.

9. The wireless sensor network according to claim 8, further comprising means for programming transmission power to a higher setting for inter-cluster head communications.

10. A routing protocol method in a wireless sensor network having a plurality of clusters, each of the clusters having a cluster head, the network further having a sink node, the method comprising the steps of

waking up a first node of the wireless sensor network, thereby energizing the first node'"'"'s systems;

having the first node listen for a first keep alive data packet on an assigned communications channel for a predetermined time period;

constituting the first node as a first cluster head if the predetermined time period has timed out without the first node receiving the first keep alive data packet;

to after constituting the first node as a first cluster head, having the first cluster head transmit a second keep alive data packet;

having the first node measure a received signal strength indication (RSSI) if the first node received the first keep alive data packet;

having the first node compare the RSSI to a threshold value;

constituting the first node as a first cluster head if the RSSI is below the threshold value;

constituting the first node as a first member node if the RSSI is above the threshold value; and

having the first node follow scheduling from a single master clock of the wireless sensor network.

11. The routing protocol method according to claim 10, further comprising having said first cluster head perform the steps of;

receiving data packets from a second member node;

serially forwarding the data packets between the cluster heads in the network for retransmission to said sink node if and only if receiving cluster heads are topologically closer to said sink node than the forwarding cluster heads in a multi-hop transmission scheme until said sink node receives said data packets.

12. The routing protocol method according to claim 11, further comprising the step of having said first cluster head periodically switch roles with said second member node in a non-random manner, whereby said second member node becomes said first cluster head and said first cluster head becomes said second member node.

13. The routing protocol method according to claim 11, wherein when a ready-to-transmit UGN (Unsynchronized Group of Nodes) node receives a keep alive transmission from one of the cluster heads, having the ready-to-transmit UGN node perform the step of transmitting its UGN node data to the cluster head that transmitted the keep alive transmission.

14. The routing protocol method according to claim 13, further comprising the step of having the cluster head receiving said UGN node data forward said UGN node data to said sink node according to said multi-hop transmission scheme.

15. A wireless sensor network MAC protocol method in a wireless sensor network having a plurality of clusters, each of the clusters having a cluster head, the network further having a sink node, the method comprising the steps of:

having a ready-to-transmit sensor data node of the wireless sensor network wait a first time until an assigned communications channel used in the wireless sensor network is free;

having the ready-to-transmit sensor data node transmit a Request-To-Send (RTS) packet on the assigned communications channel to a receiving cluster head;

having the ready-to-transmit sensor data node wait until the ready-to-transmit sensor data node has received a Clear-To-Send (CTS) from the receiving cluster head;

having the ready-to-transmit sensor data node of the wireless sensor network wait a second time until the assigned communications channel used in the wireless sensor network is free;

having the ready-to-transmit sensor data node of the wireless sensor network transmit the sensor data to the receiving cluster head; and

having the read-to-transmit sensor data node sleep after transmitting the sensor data.

16. The wireless sensor network MAC protocol method according to claim 15, wherein said ready-to-transmit sensor data node is a member node.

17. The wireless sensor network MAC protocol method according to claim 15, wherein said ready-to-transmit sensor data node is a cluster head node.

18. The wireless sensor network MAC protocol method according to claim 15, wherein said RTS and CTS packets are Unicast packets.

19. The wireless sensor network MAC protocol method according to claim 15, further comprising the step of having said receiving cluster head send an acknowledgement (ACK) packet to said ready-to-transmit sensor data node to indicate that said sensor data was successfully received.

20. The wireless sensor network MAC protocol method according to claim 15, further comprising the step of having said receiving cluster head send said CTS only if there is sufficient time available in a wake period to complete transmission and acknowledgment of said sensor data.