Space division multiple access (SDMA) for robust ad hoc vehicle communication networks

Proposes a robust, self-organizing architecture for mobile ad hoc networks. The network architecture, space division multiple access (SDMA), relies on user location information and provides users access to the communication channel based on their location. SDMA divides the geographical space, where users are located, into smaller spaces. The key element of the design is a one-to-one map between the space division and the bandwidth division of time slots, frequency division, etc. Therefore, SDMA is compatible with any multiple access scheme such as TDMA, FDMA, and CDMA. The system requirement is the user information of its location and a priori knowledge of the one-to-one map of location to the bandwidth division. The scheme is self-starting and self-maintaining. It provides collision-free access to the communication medium for the users and facilitates communication address resolution amongst the users. In addition, SDMA guarantees delay-bounded communication. The paper presents the SDMA architecture and discusses its advantages and disadvantages. Moreover, enhanced SDMA is suggested to increase bandwidth efficiency.