Wireless Multihop Transmission Route Research Articles

Gradual Route Modification in Mobile Wireless Multihop Network with Combination of Carrying and Forwarding

In a wireless multihop network, data messages are transmitted along a wireless multihop transmission route composed of a sequence of intermediate wireless nodes forwarding the data messages. However, it is difficult to detect a wireless multihop transmission route from a source wireless node to a destination one if a wireless nodes are not evenly distributed and there are some areas in which wireless nodes are sparsely distributed. Some methods have been proposed to solve this problem by combination of forwarding data messages between neighbor intermediate wireless nodes as in a usual wireless multihop network and carrying data messages to pass through such areas. In the conventional methods with the combination of forwarding and carrying data messages, some dedicated intermediate mobile wireless nodes serve the role of carrying. Hence, such nodes are required to consume more battery power which results in lower connectivity of the network. In addition, transmissions of data messages might be suspended for waiting the carrying intermediate wireless nodes which results in longer end-to-end transmission delay. In order to solve the problems, this paper proposes a novel carrying and forwarding method which gradually modifies a wireless multihop transmission route to evenly share the required mobility overhead among all the intermediate mobile wireless nodes and to reduce end-to-end transmission delay of data messages by making the route shorter. The proposed method ensures that no successive intermediate wireless nodes pass each other without neighboring.

Concurrent Data Message Transmissions for Interference of Illegal Overhearing in Wireless Sensor Networks

In wireless sensor networks, data messages containing sensor data achieved by a sensor module in a wireless sensor node is transmitted to a stationary wireless sink node along a wireless multihop transmission route in which wireless sensor nodes themselves forward the data messages. Each intermediate wireless sensor node broadcast data messages in its wireless transmission range to forward them to its next-hop intermediate wireless sensor node. Hence, eavesdropper wireless nodes within the wireless transmission range easily overhear the data messages. In order to interfere with the eavesdropper wireless nodes illegally overhearing the data messages in transmission, wireless sensor nodes whose wireless transmission ranges overlap and their next-hop intermediate wireless sensor nodes are out of the wireless transmission ranges each other forward data messages in transmission concurrently and cause collisions between these two data messages at any possible eavesdropper wireless nodes intentionally. To enhance regions where concurrently forwarded data messages intentionally collide to prevent their overhearing and to realize concurrent forwarding of data messages, this paper designes an algorithm for TDMA transmission slot assignments for more opportunities to interfere the eavesdropper wireless nodes.

Intra-Collision Avoidance with Transmission Power Control in Wireless Ad-Hoc Networks

In wireless multihop networks, collisions among wireless transmission signals from the intermediate wireless nodes cause reduction of the end-to-end data message throughput. Hence, avoidance and/or reduction of collisions between 2-hop neighbor intermediate nodes due to the hidden terminal problem is required. For the disk model wireless transmissions, RH2SWL is one of efficient the solutions. However, in a wide-area wireless multihop network where a wireless multihop trans- mission route tends to be longer, the route detection ratio tends to be lower since it becomes difficult for each intermediate wireless node to detect its next-hop node. In order to solve this problem, this paper proposes a novel routing method for a wide- area wireless multihop networks based on the SIR model. The proposed routing method configures a wireless multihop transmission route where each intermediate wireless node receives wireless signal from its previous-hop intermediate wireless node without collisions with that from its next-hop wireless node. The proposed routing method improves the route detection ratio.

Interference with Overhearing for Secure Ad-Hoc Networks

In ad-hoc networks, data messages are transmitted from a source wireless node to a destination one along a wireless multihop transmission route consisting of a sequence of intermediate wireless nodes. Each intermediate wireless node forwards data messages to its nexthop wireless node. Here, a wireless signal carrying the data message is broadcasted by using an omni antenna and it is not difficult for a eavesdropper wireless node to overhear the wireless signal to get the data message.