A cross-layer design for ad hoc wireless networks with smart antennas and QOS support

There are numerous mechanisms to guarantee the quality of service (QoS) of a wireless transmission. In many cases the application layer sends hard-QoS requirements to the lower layers without negotiation. This requirements, which are defined by specific numeric values, are usually not fulfilled because of the mobility or delay between the signalling and data send procedures. Therefore in wireless ad hoe networks it is necessary to define a new conceptual model that changes the traditional vision of QoS integration. The contribution carried out by this work is a new architecture based on the integration between the cross-layer concept and priority queueing. In this architecture, one node is aware of the state of other components of the network. The information shared between nodes includes, the medium access control (MAC) layer metrics (MLM) and the network layer metrics (NLM). The NLMs contain the network topology, path gains and transmission power while the MLMs contain the MAC layer buffer state. The case to be examined is a mobile wireless ad hoc network utilising smart antennas and Spatial Reuse TDMA. With this methodology the scheduling is improved and different QoS services are offered by using the information obtained by the cross-layer structure. In this paper the new architecture is proposed, simulation results are presented for an STDMA network, with and without the new structure, and its feasibility is analysed.