1. EE194: Wireless Networks Group #2: Joseph Cerra and Stuart Peloquin Dynamic Transmission Power Control in Wireless Ad-Hoc Networks

2. Issue from previous presentation Received signal strength does not necessarily indicate distance What is power in reference to? –dBm Can each node run different applications –Yes Do they? –Nope How do nodes keep track of power levels? –To be discussed

3. Design Built in Classes used/modified: –RouteAodv, Field, FieldInterface, MacDumb, MacAddress, NetIp, RadioNoise, RadioNoiseAdditive, RadioInfo. Designed Classes used: –Heartbeat, AppHeartbeat, MyNode. GUI Classes: –MyCanvas, MyMenu, MyButton.

4. OSI Model Radio MAC Network Application mobility AppHeartbeat.java NetIp.java Field.java, FieldInterface.java RadioInfo.java, RadioNoiseAdditive Field Mobility.java MacDumb.java Route RouteAodv.java

5. Implementation Main Function: Heartbeat.java –Setup GUI –Setup simulation createSim(nodes, length) –Placement, mobility, spacing, fading, pathloss, field, radioInfo, mapper, packetLoss –CreateNode(node#, field, placement, radioInfoShared, protMap, pl_in, pl_out) createNode –Add: radio noise, mac, network (set protocols and routing), routing, application –Hookup entities: radio, mobility, field, mac, net –Run application

6. Implementation Application Layer: AppHeartbeat.java –Neighbour entries, beats (TTL) –Message passing –Send / receive packets (ACK) –Stagger initial sleep and wake of nodes –Send random msg to random nodes –Sleep and schedule next random wakeup

7. Implementation Mac Layer: MacDumb –Neighbour entry table Mac address, RSSI, neededPower, power, beats –Process RSSI information Store RSSI information for each neighbour Interpret signal strength change from: –RSSI –Message passing history –Compute transmission time at current bandwidth –Maintain neighbour entry table –Update transmit power

8. Message Passing DataDH DataDHNH DataDHNHTSMH DataDHNHTSMHRH App Layer Network Layer Mac Layer Radio Layer DataDHNHTSMH rssi Radio Layer DataDHNH Mac Layer DataDH Network Layer Data App Layer

9. Implementation MAC layer node hash table –Neighbors(MACADDRESS) »Where MACADDRESS is a particular node Power – power sent from node RSSI – power received from node neededPower – computed power needed for reliable communications Beats – time to live

10. Implementation Computing necessary power Powerdivided = RSSI / THRESHOLD + 3 if (Powerdivided < 1) Neededpower = powerSent + powerDivided*2 Elseif (Powerdivided > 1) Neededpower = powerSent – powerDivided*2 Else // Powerdivided == 1 Neededpower = powerSent + Powerdivided Maintaining Hash If TTL == 0 Neededpower = Neededpower + 2 If Neededpower == 15 Remove entry

11. Simulation Examples In the following slides: –Simulation with node: Numerical and Graphical Power statistics Source IP address Destination IP address –Destination IP of -1 is a broadcast –Examples of: Initialization of nodes Broadcasts Power conservation Clustering

12. Sim. Example 1 – Initialization / Broadcast

13. Sim. Example 2 – Power conservation

14. Sim. Example 3 – Clustering

15. Simulation Sequence In the following slides, two complete simulations are run. Simulation timeline: Initialization ~10 beats later ~ 20 beats later ~ 30 beats later Outcome #1 Outcome #2 ~ 150 beats later

16. Initialization

17. ~ 10 beats later

18. ~ 20 beats later

19. ~ 30 beats later

20. Outcomes The outcomes of the simulation differ because of the lifetime of routes in the RouteEntryTable. When the entries in the RouteEntryTable are not refreshed often enough, the mobility rate of the nodes may destroy the integrity of the simulation power metrics. The following two simulation are examples of high and low lifetime of entries in the RouteEntryTable.

21. Outcome #1 – High route entry lifetime

22. Outcome #2 – Low route entry lifetime

23. Conclusions – JiST SWANS Pros –Java based, easy to program –Useful programming tool for simulating WSN –Easy to understand implementation –Easily to implement customized applications and data structures –Graphical user interface customizable Cons –Lacks WSN design capabilities. –No manuals or tutorials –Bytecode rewriter complicates debugging