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Nowadays, TV broadcasting has found its application in mobile terminal, however, due to the prediction structure of video coding standards, compressed video bitstreams are vulnerable to wireless channel disturbances for real-time transmission. In this paper, we propose a novel temporal error concealment method for mobile TV sequences. The proposed ordering methods utilizes continuity feature among...
The Joint Photographic Experts Group (JPEG) standard is widely used for coding still images. The JPEG standard includes two basic compression methods. A DCT-based method is specified for `lossy' compression, and a predictive method for 'lossless' compression. JPEG features a simple lossy technique known as the Baseline method which has been by far the most widely implemented method for large number...
Error resilience stereoscopic 3D video can ensure robust 3D video communication especially in high error rate wireless channel. In this paper, an error resilience method is proposed for the depth data of the stereoscopic 3D video using data partitioning. Although data partitioning method is available for 2D video, its extension to depth information has not been investigated in the context of stereoscopic...
In this paper, we establish a rate duality between the forward and reverse links of MIMO interference channel, where the reverse links are obtained by exchanging the roles of transmitters and receivers in the forward links, and the corresponding channel matrices are conjugate transpose of the forward channel matrices. Since the capacity region for general interference channel is unknown, we show that...
We consider the Gaussian interference channel with an intermediate relay. The relay is assumed to have abundant power and is named potent for that reason. A main reason to consider this model is to find good outerbounds for the Gaussian interference relay channel (GIFRC) with finite relay power. By setting the power of the relay constraint to infinity, we show that the capacity region is asymptotically...
In this paper, we introduce the three-user cognitive radio channels with asymmetric transmitter cooperation, and derive achievable rate regions under several scenarios depending on the type of cooperation and decoding capability at the receivers. Two of the most natural cooperation mechanisms for the three-user channel are considered here: cumulative message sharing (CMS) and primary-only message...
Opportunistic relaying has been recently proposed to eliminate the need of symbol synchronization and challenging code design in distributed space-time coded (DSTC) cooperation yet achieving the same diversity multiplexing tradeoff. In opportunistic relaying, the relay terminal that possesses the best relay-destination channel quality is selected by the destination for cooperative forwarding. Combining...
This paper demonstrates that growth codes, based on Raptor channel coding, allow incremental protection of H.264 video codec data-partitioned network adaption layer units. When combined with increased protection of video reference frames, in an ADSL erasure channel up to 10 dB in video quality (PSNR) can be gained through this scheme compared to equal error protection with rateless codes. Equivalent...
In this paper, we present an unequal power allocation method that exploits the hierarchical structure of JPEG2000 coded bitstream, along with the channel state information, to assign different transmission powers to different parts of the bitstream at the coding pass level. Based on the information from the JPEG2000 bitstream, we first develop a distortion model to evaluate the distortion of the reconstructed...
It was shown by Cadambe and Jafar that the interference alignment (IA) algorithm achieves the theoretical bound on degrees of freedom (DOF) for interference channel systems. However, since this method addresses the precoder design problem from the DOF point of view, some optimization processes are additionally needed in order to improve the sum rate performance. In this paper, based on the IA method,...
In this paper, we propose a linear preceding and decoding scheme maximizing the sum rate of abuser interference channel systems where each node has multiple antennas. With an iterative approach, the preceding matrices are identified by deriving the gradient of the sum rate and applying the gradient descent method. Due to non-convexity of the formulated problem, the proposed precoder cannot guarantee...
Error correcting coding is used to protect against errors introduced by transmission media. Error correcting code enables the communication systems to have a reliable transmission over noisy channels. Cognitive radio is a creative technology proposed to increase spectrum usage by allowing cognitive users to use the unused spectrum in changing environments. During the spectrum allocation for primary...
In this paper a new kind of simple-encoding irregular systematic LDPC codes suitable for one-relay coded cooperation is designed, where the proposed joint iterative decoding is performed effectively in the destination regarding the two different irregular LDPC codes used by the source and relay in ideal and non-ideal coded cooperation. The theoretical analysis and simulations show that this new cooperation...
Recently, there has been a growing interest in physical-layer network-coding techniques that facilitate information transfer in wireless relay networks. Physical-layer network-coding techniques take advantage of the additive nature of wireless signals by allowing two terminals to transmit simultaneously to the relay node. This technique has several performance benefits, such as improving utilization...
For video transmission over wireless or highly congested networks, video transcoding is typically used to reduce the rate and change the format of the originally encoded video source to match network conditions and terminal capabilities. Error resilient video transcoding can insert error resilient tools in the compressed video to enhance error resilience of the video over wireless channels by increasing...
We consider a multiple path wireless network and address the problem of coding and routing a message in a manner that guarantees both robustness and security. Each path in the network is assumed to be a wiretap channel that includes both a main channel and a wiretap monitored by an eavesdropper. We then show that Raptor codes can be used to achieve both perfect secrecy and zero error probability....
This paper describes a 12-bit 200 MHz CMOS DAC for wireless communication. The proposed DAC consists of a unit current-cell matrix for 6 MSBs and a unit current-cell matrix for 4 NSBs and a binary-weighted array for 2 LSBs. In order to ensure the linearity of DAC, a double centro symmetric current matrix is designed by using the Q2 random walk strategy. A voltage limiter circuit that limits the switching...
Emerging applications in wireless communications and software defined radio require robust and generalized decoders with a very good efficiency. This paper aims at introducing a novel and powerful method of implementing a decoder using support vector machines (SVM) to exhibit good performance irrespective of the channel model. The method proposed also ensures a generalization in the design of decoder,...
The article describes main conception how to use error protection codes to transmit digital video over wireless channels. The article describes experiments which obtain parameters for these codes, decoder behavior and some results. The objective metrics are described too.
We describe new concepts in broadband software define radio architectures optimized for very high bandwidth wireless communication protocols. This is important since a trend in wireless communication transceivers is the adoption of increasingly sophisticated radio link algorithms which maximize utility functions consisting of network capacity, data rate reliability, and throughput. Many prior efforts...
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