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In this paper, we present a low-complexity algorithm for the broadcast of three-step bidirectional relaying that decides which resources should be used for a network coding transmission, and which resources should be used for a conventional transmission. The algorithm requires a simple comparison operation for every transmission resource, and is independent from one resource to another thus enabling...
In this paper, we investigate the range of the achievable diversity order of opportunistic relay selection with M amplify-and-forward (AF) relays and N users. We show that the opportunistic selection of the relay-user pair with the best end-to-end signal-to-noise ratio (SNR) achieves a diversity order between M+N and MN+N. Our analysis reveals that the achievable diversity order depends on the SNR...
High power and spectral efficiencies are crucial on modern wireless communications. M-QAM (Quadrature Amplitude Modulation) modulations have been adopted on HSDPA (High Speed Downlink Packet Access) and satellite links, due his higher spectral efficiency. However, due to large envelope fluctuations levels, nonlinear operations such as an high power amplification are undesirable since can they lead...
Compared to simulcast, the utilization of inter-view prediction at key pictures can dramatically improve the compression efficiency of multiview video coding (MVC). The reconstructed key picture in previous adjacent view is used as the inter-view reference picture of the key picture in the current coding view. The efficiency of inter-view prediction may deteriorate due to the existence of mismatch...
Multi-view Video Coding (MVC) employs both motion and disparity estimation within the encoding process. These provide a significant increase in coding efficiency at the expense of a substantial increase in computational requirements. This paper presents a fast motion and disparity estimation technique that utilizes the multi-view geometry together with the depth information and the corresponding encoded...
In this paper, we introduce Dual-hop Spatial Modulation (Dh-SM). We look at the effect that Dh-SM has on the required signal to noise ratio (SNR) at the destination and how it can help alleviate the multi-hop burden. Initial bit-error-ratio (BER) results comparing the performance of Dh-SM with orthogonal decode-and-forward (DF) are presented where Dh-SM is shown to have up to a 10 dB SNR advantage.
Filter bank optimization for specific input statistics has been of great interest in both theory and practice in many signal processing applications. In this paper we consider biorthogonal GTD (generalized triangular decomposition) filter banks for optimizing the coding gain. We develop some theoretical results for the optimal biorthogonal GTD subband coder. We also show in both theory and numerical...
In this paper, the problem of adaptive bit and power allocation for coded OFDM systems is considered. With emphasis on low feedback overhead and low complexity, we present a simple adaptive allocation technique, where data are transmitted only using the strongest subcarriers with uniform power and uniform constellation size. Due to the reduced number of used subcarriers, a fraction of coded bits are...
This work evaluates the bit error rate (BER) performance of various two-dimensional turbo product codes (TPCs). The turbo decoder is implemented using hard-input hard-output data, which is impaired by additive white Gaussian noise (AWGN) and multipath fading. The effectiveness of the iterative TPC BER is evaluated using sequential and non-sequential decoding. Numerical simulation for different TPCs...
An efficient error protection scheme is proposed for video delivery over lossy channels. Flexible Macroblock Ordering is used to generate spatial descriptions that are sent over disjoint paths. Additionally, descriptions are partitioned to allow unequal error protection against burst errors. Experimental results show that a significant quality gain can be achieved (up to 3 dB) in the presence of burst...
In this paper, a modified SAOC (Spatial Audio Object Coding) scheme with harmonic elimination structure is proposed. The proposed structure improves the quality of vocal-removed sound and well removes a vocal object using the harmonic information of the vocal object. Subjective and objective evaluation results show the proposed scheme is superior to the conventional ones.
Walsh-Hadamard transform (WHT) based multiplierless integer discrete cosine transform (IntDCT) has structural regularity even in short word length lifting coefficients. It, however, cannot apply to image coding without the quantization part because WHT was implemented by only ±1 adder operations without the normalization scaling factors. Although we have already presented a normalized integer WHT...
FIR Unimodular Filter Banks (UFBs) offer the minimum possible delay among all the filter banks with the same downsampling rate. Although Order-one UFBs can be factorized into degree-one unimodular matrices, this factorization is not possible for higher order UFBs. This is unfavorable because in most applications, banks with longer length filters result in better performance. In this paper, we investigate...
In this paper we propose a novel method of improving the video coding efficiency. Our method combines the shot cut detection and adaptive GOP structure. We have analyzed different approaches for shot cut detection with aim to choose the most appropriate one. The next step is to situate I frames to the positions of detected cuts during the process of video encoding. Finally the efficiency of the proposed...
Cooperative Communication enables a system to achieve a significant gain in coverage and capacity. In coded cooperation, channel coding is embedded in the cooperation strategy, and the optimal level of the cooperation between the nodes needs to be determined according to the channel conditions. Using RCPC codes, we propose an adaptive approach that relies on efficient reallocation of system resources...
The video quality of the conventional single description (streaming) coding (SDC) is vulnerable to transmission errors. Once a video frame is lost, it is likely to cause error propagation to the subsequent received frames, and this increases the difficulty of whole-frame error concealment by its preceding and/or succeeding reference frames. The temporal Multiple Description Coding (T-MDC) is more...
Soft-decision forward error correction provides high coding gain, but typically with high complexity. We present a soft-decision turbo product code with >;11 dB NECG and reasonable complexity in a 40-nm ASIC for 100-Gbps applications.
The first experimental demonstration of nonbinary-LDPC-coded optical transmission is presented. Using DQPSK, we can achieve >;8dB and ~10dB net coding gains at the BER of 10-6 in the absence and presence of I/Q imbalance, respectively.
We propose nonbinary-LDPC-coded modulation schemes employing subcarrier-multiplexing and three-dimensional constellations. We improve coding gains of conventional PDM-M-QAM by 2.17dB and 2.92dB, for M = 8 and M = 16, respectively, at the BER of 10-7.
The paper presents a coding technique to improve signal to noise ratio (SNR) in an Optical Time Domain Reflectometer (OTDR). The notion lies in combining Complementary Correlation Codes and Simplex codes to achieve higher gains than conventionalcoding techniques. Simulative results show significant SNR enhancement and are in excellent agreement with theoretical equations.
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