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Ad HoC Mobile Wireless netWorks
On the other hand, if the channel quality is estimated as worse, a
higher transmission power is assigned or the transmission process
might be stopped temporarily until the communication channel is
good again.
7.4.2 MAC Techniques
Power-saving techniques existing at the MAC layer consist primarily
of sleep-scheduling protocols. e basic principle behind all sleep-
scheduling protocols is that lots of power is wasted listening on the
radio channel while there is nothing there to receive. Sleep schedul-
ers are used to duty cycle a radio between its on and off power states
in order to reduce the effects of this idle listening. ey are used to
wake up a radio whenever it expects to transmit or receive packets and ...