Wireless Network Coding for Cooperative Indoor Positioning in Cognitive Radio Networks
หัวหน้าโครงการ
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กำพล วรดิษฐ์
ทีมวิจัย
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กำพล วรดิษฐ์
หัวหน้าโครงการ
ภูมิพัฒ แสงอุดมเลิศ
นักวิจัยที่ปรึกษา
วันที่เริ่มโครงการ
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3 มิ.ย. 2556
วัตถุประสงค์
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1. Building optimization framework: To achieve the minimum delay (number of iterations), the network coding is applied to the network layer by letting nodes in the route do bit operations, i.e. XOR, instead of routing alone, so that the conventional flooding of positioning information changes to the proposed network-coded multicasting of positioning information. Also, to simultaneously achieve the maximum bandwidth efficiency, the cognitive radio is applied to the physical layer by letting agent nodes be the secondary users, which sense interference in the network and do the transmit power control, so that the communications of primary users are not interrupted. These two objectives have interaction in the manner that the transmit power control determine the set of possible routes. Hence, the optimization is formulated separately into two stages: optimizing the transmit power control of agent nodes, and optimizing the multicasting flows and agent nodes state, which is either active or inactive. The constraints include interference to the primary users, maximum transmit power, and acceptable positioning error. The optimization results serve as the performance bound for the next step.
2. Developing realistic protocol and algorithm: The interference in the network is random. In practice, hence, the optimal transmit power control cannot be planned. The agent nodes have to update the knowledge of interference in the network, and re-optimize the transmit power control. In the previous step, we assume the agent nodes to have the global knowledge of interference in the network. In this step, we will heuristically develop the realistic protocol for agent nodes to update the knowledge of interference in the network, and develop the transmit power control algorithm that takes such protocol as the input. Then, we will compare the obtained performance with the performance bound from the previous step.
3. Writing Simulator: The performance of the designed realistic protocol and algorithm has to be tested by real-world experiments or simulations. Since building a testbed for real-world experiments is specific to the chosen radio transceiver technology, we will write a simulator for testing the performance of a designed cooperative positioning, transparently to the underlying radio transceiver technology.
