This will trigger the nodes close to the border nodes to do neighbor
discovery more aggressively (say every 30 seconds, depending on the speed of
the mobile node). Consequently, a mobile node will quickly follow the schedule
of the new cluster.
4.8 Two Radio Protocols
The concept of having two radios, one for signaling and the other for data, was
first introduced in PAMAS protocol [10]. PAMAS used this idea to overcome
the problem of overhearing among neighboring nodes, thus reducing the energy
consumption. On the other hand, PAMAS did not consider idle listening
as a source of energy waste and, furthermore, it assumed that idle listening
consumes zero power.
tries to solve the idle listening problem. It uses a low power (with very low
duty cycle) wakeup radio and a primary radio for data transmission. Both the
tra?±c. If the tra?±c is high, both sender and receiver will wake up more often.
Otherwise, they will spend a longer time sleeping. To adapt their wake up
times to the network tra?±c, nodes must use a fixed size packet queue and
should have pre-knowledge of the number of neighbor nodes. Although this
wake-ups between nodes on di?®erent hops. In addition, so far there is no real
implementation for the two-radio architecture in sensor networks.
4.9 A Transmission Control Scheme for Media Access in Sensor
Networks
The goal of this protocol introduced in [15] is to achieve node fairness while
(RTS/CTC/DATA/ACK).
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