High-resolution image and video communication in home networks is highly expected to proliferate with the spread of Wi-Fi devices and the introduction of multiple-input multiple-output (MIMO) systems. This paper proposes a joint transmission and coding scheme for broadcasting high-resolution video streams over multiuser MIMO systems with an eigenbeam-space division multiplexing (E-SDM) technique. Scalable video coding makes it possible to produce the code stream comprised of multiple layers having unequal contribution to image quality. The proposed scheme jointly assigns the data of scalable code streams to subcarriers and spatial streams based on their signal-to-noise ratio (SNR) values in order to transmit visually important data with high reliability. Simulation results show that the proposed scheme surpasses the conventional unequal power allocation (UPA) approach in terms of both peak signal-to-noise ratio (PSNR) of received images and correct decoding probability. PSNR performance of the proposed scheme exceeds 35dB with the probability of over 95% when received SNR is higher than 6dB. The improvement in average PSNR by the proposed scheme compared to the conventional UPA comes up to approx. 20dB at received SNR of 6dB. Furthermore, correct decoding probability reaches 95% when received SNR is greater than 4dB.

In this paper, we propose a framework to allocate code rates of component codes in a Plotkin-type unequal error protection (UEP) code. We derive an equivalent noise variance for each component code using structure of the Plotkin construction and Gaussian assumption. Comparing the equivalent noise variance and Shannon limit, we can find a combination of the code rates for the component codes. We investigate three types of code rate combinations and analyse their UEP performance. We also estimate a performance crossing signal to noise ratio (SNR) of the Plotkin-type UEP code. It indicates that which code has better performance for a given SNR. We confirm that the proposed framework is appropriate to obtain a desired UEP capability.

In this paper, we design an Unequal Error Protection (UEP) rateless code with special coding graph and apply it to propose a novel HTTP adaptive streaming based on UEP rateless code (HASUR). Our designed UEP rateless code provides high diversity on decoding probability and priority for data in different important level with overhead smaller than 0.27. By adopting this UEP rateless channel coding and scalable video source coding, our HASUR ensures symbols with basic quality to be decoded first to guarantee fluent playback experience. Besides, it also provides multiple layers to ensure the most suitable quality for fluctuant bandwidth and packet loss rate (PLR) without estimating them in advance. We evaluate our HASUR against the alternative solutions. Simulation results show that HASUR provides higher video quality and more adapts to bandwidth and PLR than other two commercial schemes under End-to-End transmission.

Coupled with the discrete wavelet transform, SPIHT (set partitioning in hierarchical trees) is a highly efficient image compression technique that allows for progressive transmission. One problem, however, is that its decoding can be extremely sensitive to bit errors in the code sequence. In this paper, we address the issue of transmitting SPIHT-encoded images via noisy channels, wherein errors are inevitable. The communication scenario assumed in this paper is that the transmitter cannot get any acknowledgement from the receiver. In our scheme, the original SPIHT code sequence is first segmented into packets. Each packet is classified as either a CP (critical packet) or an RP (refinement packet). For error control, cyclic redundancy check (CRC) is incorporated into each packet. By checking the CRC check sum, the receiver is able to tell whether a packet is correctly received or not. In this way, the noisy channel can be effectively modeled as an erasure channel. For unequal error protection (UEP), each of those packets are repeatedly transmitted for a few times, as determined by a process called diversity allocation (DA). Two DA algorithms are proposed. The first algorithm produces a nearly optimal decoded image (as measured in the expected signal-to-noise ratio). However, its computation cost is extremely high. The second algorithm works in a progressive fashion and is naturally compatible with progressive transmission. Its computation complexity is extremely low. Nonetheless, its decoded image is nearly as good. Experimental results show that the proposed scheme significantly improves the decoded images. They also show that making distinction between CP and RP results in wiser diversity allocation to packets and thus produces higher quality in the decoded images.

This paper proposes Burst Error Resilient coding (BRC) technology in mobile broadcasting network. The proposed method utilizes Scalable Video Coding (SVC) and Forward Error Correction (FEC) to overcome service outage due to burst loss in mobile network. The performance evaluation is performed by comparing PSNR of SVC and the proposed method under MBSFN simulation channel. The simulation result shows PSNR of SVC equal error protection (EEP), unequal error protection (UEP) and proposed BRC using Raptor FEC code.

In our previous research, to achieve unequal error protection (UEP), we proposed a scheme which encodes the data by randomly switching between several codes which use different signal constellations and showed the effectiveness in AWGN channels. In this letter, we propose our UEP system using MMSE-FDE for fast and selective fading by using the fact that importance levels are changed every few symbols, i.e., every block, in the proposed system. We confirmed the improvement in BER performance and the effectiveness of adaptive equalization for the proposed system in fading channels. Moreover, in fading channels we confirmed the validity of the theoretical tradeoff shown in static conditions.

This letter proposes a practical algorithm for video transmission of the scalable extension of H.264/AVC (SVC) over limited bit-rate and varying channel signal-to-noise ratio (SNR). The proposal consists of SVC source-layer dropping and layered FEC using LDPC codes to maximize the video quality. The experimental results show that the proposed method realizes better video quality than the compared unequal error protection (UEP) without source-layer dropping. This implies that the dropping of a certain number of source-layers and using the resultant bit-budget for channel coding is more effective than the other UEP case which uses all possible source-layers.

Digital watermarking is a technique that aims at hiding a message signal in a multimedia signal for copyright claim, authentication, device control, or broadcast monitoring, etc. In this paper, we focus on embedding watermarks into still images, where the watermarks themselves can be binary sequences or grayscale images. We propose to scramble the watermark bits with pseudo-noise (PN) or orthogonal codes before they are embedded into an image. We also try to incorporate error correction coding (ECC) into the watermarking scheme, anticipating reduction of the watermark bit error rate (WBER). Due to the similarity between the PN/orthogonal-coded watermarking and the spread spectrum communication, it is natural that, following similar derivations regarding data BER in digital communications, we derive certain explicit quantitative relationships regarding the tradeoff between the WBER, the watermark capacity (i.e. the number of watermark bits) and the distortion suffered by the original image, which is measured in terms of the embedded image's signal-to-noise ratio (abbreviated as ISNR). These quantitative relationships are compactly summarized into a so-called tradeoff triangle, which constitutes the major contribution of this paper. For the embedding of grayscale watermarks, an unequal error protection (UEP) scheme is proposed to provide different degrees of robustness for watermark bits of different degrees of significance. In this UEP scheme, optimal strength factors for embedding different watermark bits are sought so that the mean squared error suffered by the extracted watermark, which is by itself a grayscale image, is minimized while a specified ISNR is maintained.

FEC (Forward Error Correction) is widely used to recover packet loss over the Internet since it does not involve additional network delay. However, FEC still needs much additional network bandwidth for redundancy, and does not consider the priority or the importance of video frames to generate redundant data. In this paper, we present Periodic FEC (PFEC) to make up for the shortcomings of FEC. PFEC divides frames into high-priority frames and low-priority frames, and gives redundancy only to high-priority frames. As specific examples, we describe two types of PFEC: Media-Independent PFEC and Media-Dependant PFEC. Moreover, based on the two-state continuous time Markov chain, we propose redundancy control algorithms of the PFEC schemes that can adjust the amount of redundancy to optimal levels depending on network loss conditions. For better performance, we also consider UEP (Unequal Error Protection) based on PFEC that gives redundancy to low-priority frames as well as high-priority frames. Experimental results show that compared with FEC, PFEC reduces the amount of redundancy considerably but degrades PSNR slightly, and UEP based on PFEC economizes redundancy without the degradation of the PSNR.

A prototype modem with unequal error protection (UEP) capability was developed using multiple block coded modulation (MBCM). Benefited from its unique structure, MBCM can be used to provide UEP straightforward. We propose a new method to increase the robustness of the carrier recovery process by taking advantage of the MBCM code structure. We also use a frame format to facilitate the synchronization operation. This modem was developed in preparation for the mobile satellite communication experiments using the Engineering Test Satellite of VIII-type (ETS-VIII). In addition of MBCM, some other types of modulation schemes have been implemented in the same modem to enable a range of communication experiments to be performed. The modem can operate at variable data rates. The results of laboratory measurements agreed well with computer simulation results. Typical link budgets based on the parameters of ETS-VIII are also presented.

Data compression is popularly applied to computer systems and communication systems. Especially, lossless compression is applied to text compression. Since compressed data are very sensitive to errors, several error control methods for data compression using probability model, such as for arithmetic coding, have been proposed. This paper proposes to apply an unequal error protection, or a UEP, scheme to LZ77 coding and LZW coding. This investigates a structure of the compressed data and clarifies a part which is more sensitive to errors than the other by using theoretical analysis and computer simulation. The UEP scheme protects the error-sensitive part from errors more strongly than the others. Computer simulation says that the proposed scheme can recover from errors in the compressed data more effectively than the conventional methods.

This paper proposes a channel monitor-based unequal error protection scheme using a dynamic OFDM subcarrier assignment technique for broadband video transmission systems in frequency selective fading environments. In the proposed system, to achieve stable regeneration of the received video, subcarriers with relatively high channel gain are assigned to the high priority data (HPD) in the MPEG data. To further guarantee a required transmission quality of the HPD, the proposed system also employs subcarrier transmission power control with delay profile information (DPI) feedback-type channel estimation technique. Computer simulation confirms that the proposed technique is effective in preventing quality degradation with about 20 dB lower transmission power than the conventional systems in frequency selective fading environments.

This letter presents a code which corrects single bit errors in any location of the word as well as l-bit burst errors occurred in an important part of the word. The proposed code is designed by product of the parity check matrix of the l-bit burst error correcting codes and the matrix which converts input unequal errors into equal errors. This letter also demonstrates the evaluation of the code, and presents the extended codes with two-level burst error correcting capabilities by interleaving.

In the wireless asynchronous transfer mode (ATM) networks, a custom data link control (DLC) layer protocol with stronger error correction ability is needed for mitigating the affect of radio channel errors. This paper applies punctured turbo code schemes to the protection of the header and various payloads in wireless ATM cell, which are realized by the combination of programmable interleaving and puncturing. Their performance is analyzed for Rayleigh fading channel, which shows more significant reduction in cell loss rate (CLR) than the previous systems. Our proposal also provides good balance designs for CLR and the payload bit error rate (BER), and offers potential for future evolutionary improvement of the wireless ATM coding scheme.

Channel coding for bandwidth limited channels based on multilevel bit-interleaved channels is discussed in this paper. This coding and decoding structure has the advantage of simplified design, and naturally incorporates flexible and powerful design of unequal error protection (UEP) capabilities, especially over time-varying channels to be often found in mobile radio communications. Multilevel coded modulation with multistage decoding, and bit-interleaved coded modulation are special cases of the proposed general framework. Simulation results verify the usefulness of the system considered.

A new UEP technique for image transmission using trellis code based on Hamming distance criterion has been proposed. The simulation results comparing the image quality and bit-rate for UEP and EEP have been provided. The results show that UEP performs better than EEP in terms of bit-rate without any significant depreciation in image quality.

Unequal error protection (UEP) is a very promising coding technique for satellite broadcasting, as it gradually reduces the transmission rate. From the viewpoint of bandwidth efficiency, UEP should be achieved in the context of multilevel coded modulation. However, the conventional mapping between encoded bits and modulation signals, usually realized for multilevel block modulation codes and multistage decoding, is not very compatible with UEP coding because of the large number of resulting nearest neighbor codewords. In this paper, new coded modulation schemes for UEP based on unconventional partitioning are proposed. A linear operation referred to as interlevel combination is introduced. This operation generalizes previous partitioning proposed for UEP applications and provides additional flexibility with respect to UEP capabilities. The error performance of the proposed codes are evaluated both by computer simulations and a theoretical analysis. The obtained results show that the proposed codes achieve good tradeoff between the proportion and the error performance of each error protection level.

In this paper, we study unequal error protection (UEP) capabilities of punctured convolutional codes. For constructing the good UEP convolutional codes, the conditional weight distributions of UEP convolutional codes are defined and evaluated. The conditional weight distributions are computed by using the transfer functions of time-varying trellis structures of punctured convolutional codes. The best UEP convolutional codes from the viewpoint of the weight distributions are listed.

This paper proposes and investigates a coding and decoding scheme to achieve adaptive unequal error protection (UEP) using several convolutional codes which have different error-correcting capabilities. An appropriate encoder is selected to unequally protect each frame of information sequence according to the importance of the frame. Since the supplemental information of selected encoder is not sent for the sake of reducing redundancy, we assume that the decoder does not know which encoder was used, and the decoder has to estimate the used encoder. In order to estimate which encoder was used, the method using biased metric in Viterbi decoding is proposed. In decoding, however, there is a problem of Decoder-Selection-Error (DSE), which is an error that the decoder selected in a receiver does not correspond to the encoder used in a transmitter. An upper bound of DSE rate in decoding is derived. The proposed decoding scheme using the biased metric in a trellis can improve DSE rate and BER performance, because transition probability of encoders is taken into account in calculating likelihood by means of making branch or path metric biased. Computer simulation is employed to evaluate the BER performance and DSE rate of the proposed scheme. The performance is compared with a conventional equal error protection scheme and a UEP with the supplemental information on the used encoder. It is found that the proposed scheme can achieve better performance than them in case N=2.

In this paper, the error performance of block coded 8-PSK modulation systems of length 32, designed for unequal error protection (UEP) of messages transmitted over a Rayleigh fading channel, is investigated. Computer simulation are reported showing that, with transmission over a Rayleigh fading channel, a good improvement in coding gain is obtained by the use of a binary linear UEP (LUEP) code as a constituent code in the multilevel construction, compared with conventional block coded modulation (BCM) of the same length.