H. Wicaksana

Nanyang Technological University, Singapore, Singapore

Are you H. Wicaksana?

Claim your profile

Publications (7)5.92 Total impact

  • H. Wicaksana, S.H. Ting, Y.L. Guan, X.-G. Xia
    [Show abstract] [Hide abstract]
    ABSTRACT: Two-path or successive relaying has recently emerged as a promising cooperative communication protocol to improve spectral efficiency in half-duplex relaying networks. In this paper, we consider decode-and-forward (DF) version of the two-path relaying protocol. We analyze the fundamental performance of this protocol in terms of the diversity-multiplexing tradeoff (DMT). We first derive the DMT for this protocol, where perfect decoding at the relays is assumed, and show that it approaches the 3 x 1 multiple-input single-output (MISO) DMT. We then remove the assumption of perfect decoding at the relays and derive the closed-form expression of the achievable DMT based on the relative distances between nodes. Specifically, we found that for sufficiently long transmission length, if the average source-relay SNR is at least 2.5 times (measured in dB) of other links, the 3 x 1 MISO DMT is achieved. Successive interference cancellation at the relays is also proposed to further improve the performance of the DMT.
    IEEE Transactions on Communications 08/2011; · 1.75 Impact Factor
  • H. Wicaksana, S.H. Ting, M. Motani, Y.L. Guan
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, an amplify-and-forward (AF) two-path half-duplex relaying scheme is considered in which one of the relays additionally performs inter-relay interference cancellation. We first generalize lower bounds for the diversity-multiplexing tradeoff (DMT) of an arbitrary block lower triangular channel matrix. We then characterize the diversity-multiplexing tradeoff for the AF two-path relaying scheme and show that the DMT achieves the multiple-input single-output (MISO) upper bound. The analysis also demonstrates that, with a careful choice of the coding strategy, the DMT of this scheme is achievable for finite codeword lengths. We then propose using an equivalent linear space time code at the source, which does not require any form of channel state information, as a simple and effective coding strategy to achieve the full DMT of the scheme. From the DMT perspective, the proposed AF two-path relaying with the equivalent linear space time coding outperforms existing schemes. Our analysis is then extended to the slotted-amplify-and-forward (SAF) scheme with multiple relays, where we provide a stronger result by deriving the DMT while taking into account inter-relay interference.
    IEEE Transactions on Communications 01/2011; · 1.75 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we consider a network consisting of one source, one destination and two relays, under a half duplex constraint. We analyze an amplify-and-forward (AF) two-path relaying scheme where one of the relays additionally performs inter-relay interference cancellation. With this inter-relay self interference cancellation, we show that degradation in performance can be significantly reduced when inter-relay channel gain increases. By treating the AF two-path relaying as an equivalent MIMO space time code, we derive an upper bound for the pairwise error probability (PEP) of this system. Previous works indicate that only a diversity order of two can be achieved even though physically there are three possibly independent spatial paths to the destination. From our analysis of the PEP, we analytically prove and identify the reason to the limited diversity order of two. We then propose a simple but novel precoding scheme which allows the system to achieve a full diversity order of three while maintaining the spectral efficiency gain of the two-path relaying protocol. A robust precoding design to achieve full diversity order with high coding gain is also proposed. Index Terms—Amplify-and-forward, half duplex relaying, two-path relaying, diversity order, precoding.
    IEEE Transactions on Wireless Communications 01/2009; 8:4720-4729. · 2.42 Impact Factor
  • Source
    H. Wicaksana, See Ho Ting, Yong Liang Guan
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we present a novel spectral efficient relaying scheme for a random linear fountain code with two half duplex relay nodes at which simple network coding, which consists of an XOR operation, is performed. Only the destination node will have a fountain decoder. At the relay nodes, the received packets will be CRC decoded<sup>1</sup> and randomly XOR with the earlier correctly CRC decoded packets which are stored in the relays' buffers. If the received packets cannot be correctly CRC decoded, the relays will just randomly XOR the packets in their respective buffers and forward the newly network coded packet to the destination. The theoretical upper bound for the outage probability of this proposed scheme is derived. Our simulation results show that the upper bound is tight and the proposed scheme outperforms existing schemes. It is also shown that with wireless network coding, 1-2 dB performance gains and faster fountain decoding especially for low SNR can be achieved.
    Communications Workshops, 2008. ICC Workshops '08. IEEE International Conference on; 06/2008
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we analyze a full rate cooperative communication system using amplify-and-forward (AF) two-path relaying scheme with inter-relay interference cancellation at the relay. By treating AF two-path relaying as an equivalent MIMO system, we derive the pairwise error probability (PEP) of this system. Given one source node, two half duplex relay nodes, and one destination node, all equipped with single antenna, our theoretical analysis and simulation results show that diversity order of 2 can be achieved by this system. Furthermore, with inter-relay interference cancellation, degradation in performance can also be significantly reduced when inter-relay channel gain increases. Our analysis also shows that diversity order of the system will not be affected by the magnitude of this inter-relay channel gain.
    Vehicular Technology Conference, 2008. VTC Spring 2008. IEEE; 06/2008
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this paper, we analyze a full rate cooperative communication system using amplify-and-forward (AF) two-path relaying scheme with inter-relay interference cancellation at the relay. By treating AF two-path relaying as an equivalent MIMO system, we derive the pairwise error probability (PEP) of this system. Given one source node, two half duplex relay nodes, and one destination node, all equipped with single antenna, our theoretical analysis and simulation results show that diversity order of 2 can be achieved by this system. Furthermore, with inter-relay interference cancellation, degradation in performance can also be significantly reduced when inter-relay channel gain increases. Our analysis also shows that diversity order of the system will not be affected by the magnitude of this inter-relay channel gain.
    Vehicular Technology Conference, 2008. VTC Spring 2008. IEEE; 01/2008
  • Source
    H. Wicaksana, S. Hartono, Foo Say Wei
    [Show abstract] [Hide abstract]
    ABSTRACT: In this paper an automated method to recognize the musical instruments playing the musical signals is presented. Various features of the musical instruments and musical signals are investigated. The features can broadly be grouped into three categories: temporal, spectral, and cepstral features. A composite neural network structure is proposed as the classifier. The performance of the composite neural network using a set of carefully chosen features is compared with that of the traditional neural network. Experimental results show that the accuracy achieved using composite structure (94%) is significantly higher than that using the traditional structure (88%) when more than four musical instruments are to be distinguished
    Circuits and Systems, 2006. APCCAS 2006. IEEE Asia Pacific Conference on; 01/2007