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HCRBT: a dual-busy-tone-assisted MAC protocol with channel reservation for Ad Hoc networks. Yi CHEN and Bo LI IEEE WiCOM 2011 Speak: Huei -Rung, Tsai. Outline. Introduction Goal HCRBT protocol Results and discussions Conclusions. Introduction.
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HCRBT: a dual-busy-tone-assisted MAC protocol with channel reservation for Ad Hoc networks Yi CHEN and Bo LI IEEE WiCOM 2011 Speak: Huei-Rung, Tsai
Outline • Introduction • Goal • HCRBT protocol • Results and discussions • Conclusions
Introduction • Channel reservation MAC protocols are proposed to guarantee higher level of QoS for real-time traffic requires in wireless Ad Hoc networks • In some protocols, real-time node reserves channel by a piggyback broadcast of Channel Reservation Information (CRI)
Introduction • However, the CRI reception is not guaranteed because the packet transmission may be affected due to hidden/exposed terminal problem • DBTMA protocol with dual busy tone can solve the hidden/exposed terminal problem
Introduction • How to Solve the Hidden/Exposed Terminal Problem • Use busy tones to replace the responding packets (CTS and ACK) Exposed terminal node can be Receiver B A C D E can be Sender Hidden terminal node
Introduction • How to Solve the Hidden/Exposed Terminal Problem TransmissionRange InterferingZone of A InterferingZone of B A B Carrier sensingRange • Node in transmission range can correctly receive and decode packets • Node in carrier sensing range sense the data transmission and the setup of busy tones
Goal • Propose a new MAC protocol, namely Hybrid of Channel Reservation and Busy Tone(HCRBT) • Solve hidden/exposed terminal problem • Supportreal-time traffic transmission • hybrid scheme of channel reservation and dual busy tone
HCRBT • How to Solve the Hidden/Exposed Terminal Problem • DBTMA • Three channels : BTt/ BTr / data 1.CTS 2.Alert neighbors RTS sensing BTt of S RTS DATA S RTS DATA sensing D DATA sensing BTr of D time
HCRBT • According to the traffic types, there are two kinds of busy tones • real-time busy tone (RBT) • non-real-time busy tone (DBT)