Browsing by Author "Chan, Yu-Wei"

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35 An Effective Routing Protocol with Guaranteed Route Preference for Mobile Ad Hoc Networks
(2014)
Chien, Feng-Tsun
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Wu, Kuo-Guan
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Chan, Yu-Wei
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Chang, Min-Kuan
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Su, Yi-Sheng
Battery power and queue conservation are critical issues in mobile ad hoc network (MANET). These two factors not only affect the delivery ratio but also the lifetime of the network. In this work, we will propose a simple and effective routing protocol to extend the lifetime and to evenly distribute the traffic loads of the networks as possible. Furthermore, a concept of serving capacity is introduced to reflect the level of congestion around a node. In this way, the proposed routing protocols can avoid network congestion and achieve higher packet delivery ratios. The extensive computer simulation is conducted to compare the proposed protocol against many existing routing protocols. The results show that the proposed routing protocol can have better performance in terms of queueing length, lifetime, and packet delivery ratio and have comparable end-to-end delays.
A Coalitional Graph Game Approach for Minimum Transmission Broadcast in IoT Networks
(2020-01-01)
Chan, Yu-Wei
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Chien, Feng-Tsun
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Chang, Min-Kuan
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Ho, Wei-Chun
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Hung, Jason C.
In this work, we consider the broadcast mechanisms for both reliable links and unreliable links in the Internet of Things (IoT) networks. Focusing on the minimum transmission broadcast (MTB) problem, we propose an efficient algorithm, termed as the Connected Dominating Set Algorithm based on Coalitional Graph Game (CDSA-CGG), to find the minimum connected dominating set (MCDS). Distinct from related work in the literature which adopts a non-cooperative game approach and assumes the interaction among nodes is limited to neighboring nodes, we formulate the interaction and cooperation among nodes over reliable links and over unreliable links as a connected forwarding graph based on coalitional graph game. We prove that the forwarding graph constructed by CDSA-CGG is a Nash network. In addition, we also prove that the final resulting graph is pairwise stable. The simulation results show that the proposed coalition graph game-based algorithm performs well in terms of the number of transmissions, convergence rate, and lifetime of nodes.
Coalitional Game Formulation for Multi-Channel Cooperative Cognitive Radio Networks
(2011)
Chan, Yu-Wei
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Chang, Ronald Y.
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Chien, Feng-Tsun
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Chang, Min-Kuan
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Chung, Yeh-Ching
In this paper, we study a coalitional game approach to resource allocation in a multi-channel cooperative cognitive radio network with multiple primary users (PUs) and secondary users (SUs). We propose to form the grand coalition by grouping all PUs and SUs in a set, where each PU can lease its spectrum to all SUs in a time-division manner while the SUs in return help the data transmission of PUs by relaying. The grand coalition is shown to be stable in the considered scenario by justifying that the solution concept of the coalitional game (the core) is nonempty. Also, optimal relay strategies of SUs, to relay or to transmit its own data, are obtained so that the sum rate of all PUs and SUs is maximized. Finally, we demonstrate in simulation the benefits of the grand coalition comparing to the case of direct transmission only and other forms of coalitions as well.
Coalitional Power Control and Time Allocation for Multiuser Cognitive Networks
(2013-09-01)
Chan, Yu-Wei
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Chien, Feng-Tsun
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Park, James J.
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Hung, Jason C.
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Yen, Neil Y.
This paper considers the problem of resource allocation for a cooperative cognitive radio network with multiple primary users (PUs) and multiple secondary users (SUs), in which secondary users (SUs) relay traffics for primary users, in exchange for dedicated transmission time for their own transmission needs. However, since the PUs and SUs are rational, they aim at maximizing their own utility. Therefore, the problem of conflicting interests between them exists. We formulate the problem as a coalitional game to analyze the cooperation behavior between PUs and SUs. We propose to form the grand coalition by grouping all PUs and SUs in a set, and to use the core and the Shapley value solution concepts, respectively to analyze the stability and fairness of cooperative resource allocation. The optimal fraction of time allocation and power allocation for PUs and SUs are derived by an iterative updating algorithm, respectively. Simulation results show the benefits of our proposed approach as compared with other approaches.
Interference-Aware Mode Selection for New Arriving Devices in D2D Communications
(2018-01-01)
Hu, Chia-Wei
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Chien, Feng-Tsun
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Yang, Chao-Tung
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Chan, Yu-Wei
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Min, Geyong
In this work, we consider mode selection mechanisms for device-to-device (D2D) communications underlaying a cellular network with multiple existing active D2D pairs. Focusing on the mode selection of the new arrival D2D pair with existing D2D pairs and cellular users, we study the mode selection rules based on the signal-to-interference plus noise ratio (SINR) of the new arrival user and the overall system capacity. For each selection rule, we utilize and discuss pros/cons of two different sets of precoders. In the first set of precoder choice, the block diagonalization (BD) is implemented among cooperating cellular users while zero forcing (ZF) is adopted for the D2D users. In the second set, the maximum signal-to-leakage-and-noise ratio (SLNR) precoder is employed for both cellular users and D2D pairs. The simulation results show that the underlay mode is the best option for the new arrival D2D pair.
Mode Selection and Spectrum Allocation in Coexisting D2D and Cellular Networks with Cooperative Precoding
(2019-12-02)
Chan, Yu-Wei
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Chien, Feng-Tsun
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Yang, Chao-Tung
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
In this paper, we investigate the mode selection strategies for a new device-to-device (D2D) pair becoming active in a network with a number of existing D2D sensors or users coexisting with cellular users in a D2D-enabled heterogeneous network. Specifically, we propose two selection rules, the signal-to-interference-plus-noise-ratio (SINR)-based and the capacity-based, combined with two sets of different precoding schemes and discuss their impacts on the system under a variety of scenarios. While the cooperative block diagonalization (BD) among the cellular users combined with the zero-forcing (ZF) precoding among D2D users can eliminate interference observed at the new D2D receiving sensor, the maximum signal-to-leakage-and-noise-ratio (SLNR) precoding is often a preferred option due to low-complexity implementations and comparable performance. We note that the two selection rules, the SINR-based and the capacity-based, considered in this paper impact on the system differently, with interesting tradeoff from different perspectives. Finally, we provide insights by simulations into the best selection among the three modes depending on a variety of use cases in the network.
Spectrum sharing in multi-channel cooperative cognitive radio networks: a coalitional game approach
(2013-10-01)
Chan, Yu-Wei
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Chien, Feng-Tsun
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Chang, Ronald Y.
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Chang, Min-Kuan
;
Chung, Yeh-Ching
In this paper, we study a coalitional game approach to resource allocation in a multi-channel cooperative cognitive radio network with multiple primary users (PUs) and secondary users (SUs). We propose to form the grand coalition by grouping all PUs and SUs in a set, where each PU can lease its spectrum to all SUs in a time-division manner while the SUs in return assist PUs' data transmission as relays. We use the solution concept of the core to analyze the stability of the grand coalition, and the solution concept of the Shapley value to fairly divide the payoffs among the users. Due to the convexity of the proposed game, the Shapley value is shown to be in the core. We derive the optimal strategy for the SU, i.e., transmitting its own data or serving as a relay, that maximizes the sum rate of all PUs and SUs. The payoff allocations according to the core and the Shapley value are illustrated by an example, which demonstrates the benefits of forming the grand coalition as compared with non-coalition and other coalition schemes.
Spectrum Trading in Cognitive Radio Networks Using Multistage Bayesian Game
(2015)
Chien, Feng-Tsun
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Chang, Ronald Y.
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Chan, Yu-Wei
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
In this paper, we study spectrum trading in cognitive radio (CR) networks with multiple primary services (PSs) and multiple secondary services (SSs) from a game-theoretic perspective. We propose a multistage Bayesian game-based trading model which accounts for unknown private information of players (for example, the number of user connections in PSs may be unknown to the SSs) as in practical network scenarios. The perfect Bayesian equilibrium (PBE) is derived by solving an involved sequential optimization problem. We formulate the joint Karush-Kuhn-Tucker (KKT) conditions and use the KKT translation technique to obtain the PBE at each stage. Simulation demonstrates the convergence of the sequence of strategies in the multistage Bayesian game.