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Recent advances in rateless codes facilitate the utilization of dense constellation. By exploiting more constellation points with controlled symbol distance, they ensure higher transmission date rate and better diversity gain against fading. In this paper, we observe that there exists certain redundancy in the existing dense constellation diagram. With proper design, such redundancy can be can be...
This paper proposes and investigates an effective error control scheme using channel state information (CSI) for Body Area Network (BAN). In February 2012, an international standard of WBAN, IEEE802.15.6, was published and it supports error control schemes. This standard also defines seven different QoS modes. However, how to utilize them is not clearly specified. In this paper, an effective method...
Communication over a fading channel in a wireless storage system makes repair transmissions prone to physical layer errors. The repair transmission can be modeled as a multiple access channel (MAC), where multiple helpers are simultaneously communicating to the newcomer node. The existing optimal MAC space-time (ST) codes are, however, practically useless due to exponentially high decoding complexity...
The space-time coding can provide a diversity gain for the multiple-antenna system while spatial multiplexing provides higher data rates. In this paper we are combining space-time block code (STBC) with spatial multiplexing technique over space to take advantages of both schemes. The transmit antennas are divided into groups, with one of the groups transmitting STBC code given by Alamouti and other...
The modified Distributed Space Time Block Code (DSTBC) was proposed to consider possible information exchange errors. In this paper, we add one more transmitting antenna and propose the modified Hybrid MIMO Transceiver Schemes (HMTs) to maintain diversity even if all information exchange are in errors. The data rate of the proposed modified HMTs is doubled as compared to the previous modified DSTBC...
Cooperative communication has been recently proposed as a way to improve the performance of wireless communication. However, due to the half duplex constraint, most of the relay networks face a fundamental challenge in terms of multiplexing loss. In this paper, we present an adaptive cooperation via relay selection (ACRS) protocol that improves spectral efficiency. This protocol lets the source transmit...
In wireless decode-and-forward (DF) relaying networks, the hybrid ARQ (HARQ) process suffers severe latency, especially when centralized scheduling is employed. We propose a new distributed HARQ based cooperative relaying (DHCR) protocol to reduce the latency. Based on the reception quality of the 1st hop, each relay station (RS) independently processes and forwards the data stream in such a manner...
Notice of Violation of IEEE Publication Principles"Precoder Division Multiplexing Access for Cognitive Radio"by Lei Wang, Baoyu Zheng, Jingwu Cui, Xiaorong Xuin the Proceedings of the International Conference on Wireless Communications&Signal Processing, 2009. WCSP 2009 , November 2009After careful and considered review of the content and authorship of this paper by a duly constituted...
In this paper, the optimal decoding strategy for cooperative spatial multiplexing (CSM) aided systems is derived. In CSM systems, the multiple relay stations (RSs), which compose a virtual antenna array (VAA), independently decode the packets received from the mobile stations (MS) and forward them to the base station (BS). When the BS decodes the signal forwarded from the RSs, the potential decoding...
We consider the problem of broadcasting independent sources in a dense wireless network. We propose a fully decentralized scheme with minimal overhead that uses physical layer cooperative transmission with decode and forward relaying. We characterize the propagation of the source flows across the network and show that in the limit of an infinitely dense network, the relaying proceeds in levels. We...
This paper derives bounds on the diversity- multiplexing tradeoff of wireless relay networks with arbitrary link connectivity between cooperating terminals. The derived bounds are applicable when there are single and multiple antennas per terminal. Two classes of relaying method are analyzed, those requiring all cooperating terminals to correctly decode the transmitted signal in order for the destination...
In this paper, we propose an unequal error protection (UEP) scheme for multimedia transmission over wireless decode-and-forward (DF) relay networks. We prove that relay selection combining (R-SC) mode yields a better error rate performance than all-participate relays, i.e., distributed space-time codes (DSTC) and orthogonal transmission with maximum ratio combining (OT-MRC) at the destination. Hence,...
Multiple antenna wireless technology and orthogonal frequency division multiplexing (OFDM) have the potential to enable high data rate wireless applications. While the multiple-input multiple-output (MIMO) wireless techniques exploit spatial domain for improving the quantity and reliability of the data transmitted, OFDM converts the frequency-selective broadband channel into a bank of narrow band...
In many DSP applications (image and voice processing, baseband symbol decoding in high quality communication channels) several dBs of SNR loss can be tolerated without noticeable impact on system level performance. For power optimization in such applications, voltage overscaling can be used to operate the arithmetic circuitry slower than the critical circuit path delay while incurring tolerable SNR...
In this paper, an adaptive detection technique for MIMO-OFDM system is proposed. To execute the adaptive detection, existing SMLD technique is considered. The proposed technique selects proper values of V of the SMLD scheme to each subcarrier according to its estimated received power. To estimate the received power, two estimation modes are presented (noise value estimation mode with a preamble and...
Some communication applications, like multimedia, deliver data of different importance classes allowing unequal error protection (UEP) levels. In this paper, a multiple-input multiple-output (MIMO) system using orthogonal frequency division multiplexing (OFDM) is considered with a new UEP bit-loading algorithm based on the non-UEP algorithm by Chow, Cioffi, and Bingham. In the proposed bit-loading...
A new construction of a full-diversity full-rate space-time block code (FDFR-STBC) is presented in this paper. The design is for 2 transmit antennas and 2 time slots. The code outperforms the previous FDFR-STBC codes in [3], [4], [5], [6] for 1 receive antenna. We reduce the decoding complexity by exploiting the algebraic structure of the code and using the hybrid maximum-likelihood interference cancellation...
Correlative minimum shift keying (MSK), a second order polynomial modulation scheme known as tamed frequency modulation (TFM), is a constant envelope type of modulation with a perfect peak to average power ratio (PAPR), besides the property of low out of band power. We apply the linearized TFM to the single carrier transmission with frequency domain equalization (SC/FDE) concept. We then obtain a...
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