Topology control not only achieves the objective of power saving but also increases the system throughput by increasing the spatial reuse of communication channels. However, there exists a hidden terminal problem due to asymmetric transmission radii among nodes after topology control. In this paper, we propose a distributed protocol that deals with topology control at network layer and hidden terminal problem at MAC layer. Each node in the networks determines its power for data transmission and control packets transmission according to the received beacon messages from its neighbors. The proposed protocol works without location information and uses little control packet overhead to prevent the potential collisions due to the hidden terminals. Simulations show that our protocol significantly decreases total power consumption in the networks and has a better network throughput compared to previous work.

Bluetooth is a low cost, low power, short-range radio technology used for wireless personal area networks (PANS). Bluetooth scatternet is a set of piconets interconnected via bridge devices. Good interpiconet schedulings are necessary for bridge devices to switch among piconets they participate in. This paper proposes an interpiconet scheduling algorithm named "Traffic-Aware Scatternet Scheduling" (TASS), for bridges in Bluetooth scatternets. According to masters' traffic information, TASS can adaptively switch the bridge to high traffic load masters, and increase the usage of the bridge. In addition, TASS can reduce the number of failed "unsniffs" and the overhead of "bridge switch wastes" to further increase overall system performance. Simulation results show that TASS outperforms existing interpiconet scheduling in both network throughput and adaptability for various traffic loads.

The paper proposes an efficient distributed protocol to find a subset of connected sensor nodes to cover the queried region. Each node determines whether to be a sensing node to sense the queried region according to its priority, which is represented by the remaining power or sensing area within the queried region. The proposed protocol can efficiently construct a subset of connected sensing nodes and respond the query request to the sink node. Simulation results show that the proposed protocol is more efficient and has a lower communication overhead than the existing protocol.

Mobile ad hoc networks (MANET) comprise mobile hosts in a network bereft of base stations and characterized by a highly dynamic network topology. The MANET environment contains unpredictable obstacles, such as mountains, lakes, buildings, or regions without any hosts, impeding or blocking message relay. This study proposes geocasting protocol for sending short message from a source host to a geocasting region in ad hoc networks. The proposed protocol keeps messages away from unpredictable obstacles and creates a small flooding region. Experimental results show that a source host can send a short message to all hosts located in geographical area with a high success rate and low flooding overhead.