| Summary: | 碩士 === 臺灣大學 === 電信工程學研究所 === 98 === To support high-volume transmission such as wireless high definition (HD) video streaming,
multi-gigabit per second transmission is needed. The unlicensed 60 GHz band with 7-GHz bandwidth
has become the most feasible solution to support such high data rate wireless communication.
Directional antennas are used to compensate high attenuation in 60 GHz band so as to extend
the transmission range. The use of directional antennas raises new issues such as directional
hidden node problem and spatial reuse. Directional hidden node problem is the major problem for
wireless devices to discover each other.
The ECMA-387 standard is a total solution for the 60 GHz communication, from PHY layer,
MAC layer to the HDMI protocol adaptation layer (PAL). The ECMA-387 standard proposes a
protocol to enable automatic neighbor discovery. The discovery mechanism is based on self
advertisement with random switching of antenna sectors. With random switching, wireless
devices may point their antennas to each other (so called match in direction) and thus,
discover each other. However, such a neighbor discovery mechanism does not guarantee the
time of match in direction.
In this thesis, we proposed a differential-rate switching protocol to guarantee the time of
match in direction. We implemented the protocol in Opnet Modeler and showed the performance
guarantee. We also conducted simulations to study the impacts of side lobes of an imperfect
directional antenna on the performance. Coexistence protocols of the ECMA-387 standard was
also implemented and simulated. With the simulation results, we can find the best settings
according to different network environments.
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