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As a scientific field, the history of pre-islamic times is an innovation of the colonial period, in Morocco as well as in the rest of the Maghreb. The colonial ideological matrix having influenced the historical narratives of the prehistoric, protohistoric, and especially ancient periods, the nationalist historians applied themselves to “decolonizing” those times. This process of reappropriation had been ongoing for several decades, leading to a morocconization of archaeological research institutions and institutions in charge of historiographical activity, first and foremost universities. After its golden age during independence, Moroccan archaeology underwent a period of decline after 1963 before its renewal from the 1980s onwards. The revival of archaeology as observed from this point onwards has been achieved through international cooperation. Since independence, progress made possible by archaeological research has been able to offer historians and prehistorians further sources, renewing historiographical trends and research subjects., En tant que champ scientifique, l’histoire des périodes préislamiques est une innovation de la période coloniale, au Maroc comme dans le reste du Maghreb. La matrice idéologique coloniale ayant fortement déteint sur les récits historiques concernant les périodes préhistorique, protohistorique et surtout antique, les historiens nationalistes ont dû s’atteler à les « décoloniser ». Ce processus de réappropriation a duré plusieurs décennies, donnant lieu à une marocanisation des institutions de la recherche archéologique et des institutions en charge de l’activité historiographique, en premier lieu les universités. En plein âge d’or lorsqu’intervient l’indépendance, l’archéologie marocaine a connu une phase de déclin après 1963, puis une période de renouveau à partir des années 1980. Le renouveau de l’archéologie observé depuis cette date s’effectue sous le signe de la coopération internationale. Depuis l’indépendance, les progrès permis par la recherche archéologique ont permis d’offrir aux historiens et aux préhistoriens de nouvelles sources, renouvelant les tendances historiographiques et les sujets d’étude.

OpenAirInterface is an experimental open-source real-time hardware and software platform for experimentation in wireless communications and signal processing. With the help of OpenAirInterface, researchers can demonstrate novel ideas quickly and verify them in a realistic environment. Its current implementation provides a full open-source software modem comprising physical and link layer functionalities for cellular and mesh network topologies. The physical (PHY) layer of the platform targets fourth generation wireless networks and thus uses orthogonal frequency division multiple access (OFDMA) together with multiple-input multiple-output (MIMO) techniques. The current hardware supports 5 MHz bandwidth and two transmit/receive antennas. The media access (MAC) layer of the platform supports an abundant two-way signaling for enabling collaboration, scheduling protocols, as well as traffic and channel measurements. In this paper, we focus on the mesh topology and show how to implement a single-frequency mesh network with OpenAirInterface. The key ingredients to enable such a network are a dual-stream MIMO receiver structure and a distributed network synchronization algorithm. We show how to implement these two algorithms in real-time on the OpenAirInterface platform. Further more, we provide results from field trials and compare them to the simulation results.

In this work, we study fundamental limitation to the performance of time-delay estimation schemes of IR-UWB signals. We are specially interested in deriving lower bound on the mean square error (MSE). As UWB systems are expected to operate at low signal-to-noise ratio (SNR) (80211.15.4 low-power low rate standard), the improved Ziv-Zakai lower bound (IZZLB) [1] is then more suited to characterize the lower bound on the MSE, than the Cramer-Rao lower bound (CRLB). We express then the lower bound on MSE of maximum likelihood estimator based on perfect knowledge of the 2nd order statistics of the received signal by mean of the IZZLB.

A novel medium access control protocol for multiple channels ad hoc networks is presented. SEBROMA (self-balanced receiver-oriented MAC) is fully distributed, code assignment free and does not need global network synchronization. The proposed scheme is analyzed through Markov chain modeling in multihop configuration and in saturation condition.