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Wireless Ad Hoc and Sensor Networks

Wireless Ad Hoc and Sensor Networks

Wireless Ad Hoc and Sensor Networks

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412 <strong>Wireless</strong> <strong>Ad</strong> <strong>Hoc</strong> <strong>and</strong> <strong>Sensor</strong> <strong>Networks</strong>3530Channel fadingOEDSR% of packets dropped25201510510 12 14 16 18 20 22 24 26 28Noise level (dB)30FIGURE 8.45Packets dropped with channel fading.Node mobility is generated in a r<strong>and</strong>om manner for each node but waskept the same when testing protocols.Figure 8.46 shows the comparison of energy consumed by the OEDSR<strong>and</strong> the OEDR for a mobile network. As expected <strong>and</strong> observed in previousscenarios, the energy consumed using the OEDSR increases significantlyas the number of nodes increases in the network, because the nodes inthe network move in a r<strong>and</strong>om fashion. Due to this, the different routeshaving varying number of RNs are selected at different times. However,the energy consumed in the OEDSR is far less compared to the OEDRdue to the reasons mentioned in the static node case.The average E2E delay is still lower for the OEDSR when compared tothe OEDR as observed in Figure 8.47. Even with node mobility, fewernodes are selected as RNs in the OEDSR protocol, whereas the numbersof RNs are significantly more with the OEDR, which in turn, increase theE2E delay. The E2E delay includes the wake-up time for a node, apartfrom the transmission time. Therefore, with more RNs, waking, processing,<strong>and</strong> queuing times go up increasing the E2E delay.It can be observed from Figure 8.48 that the number of collisions in thenetwork is fewer for the OEDSR when compared with the OEDR. TheOEDR uses more RNs to transmit data from the CHs to the BS. Moreover,when selecting the MPR nodes, the nodes send information to their onehop<strong>and</strong> two-hop neighbors, <strong>and</strong> this increases the number of signals

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