| Summary: | unicationtechnologies, the millimeter wave (mmWave) bands are consideredas a promising candidate to extremely high data rate access in futurewireless networks. MmWave communications exhibit high attenuations,vulnerability to obstacles, and sparse-scattering environments. The smallwavelengths of mmWave signals make it possible to incorporate many antennaelements both at the transmitters and at the receivers, which lead tohigh antenna gains. This demands a reconsideration of almost all designaspects in mmWave networks compared to the traditional networks, especiallyat the medium access control (MAC) layer. Blockage affects heavilythe performance of mmWave networks. How to model blockage and itsimpacts on the key performance indicators are largely open problems.In this thesis, a new blockage model is introduced, which allows evaluatingthe impact of penetration loss due to obstacles on the fundamental performanceindicators including achievable throughput and delay. Using thisblockage model, the achievable throughput and delay of two solution approachesto overcome blockage, namely fallback and relay, is investigated.The analysis highlights an interesting correlation between blockage periodand the importance of using one technique or the other one. Afterwards, adelay analysis is proposed to focus on more realistic scenarios. Such an analysisis then used to characterize the throughput-delay tradeoff. The lattersection allows to explore the impact of the main network parameters suchas beamwidth, obstacle occurrence, blockage period, transmission time andalignment overhead. A general framework is proposed, in which it is shownunder which condition which option is preferable, from throughput-delayperspective, at the transmitter to mitigate the blockage problem. Moreover,it shows the situations under which these two techniques are notfeasible in order to fulfil some throughput-delay requirements. Simulationsare presented in order to validate the equations used at the performanceanalysis.
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