Efficient unequal error protection for online fountain codes

In this paper,an efficient unequal error protection(UEP)scheme for online fountain codes is proposed.In the buildup phase,the traversing-selection strategy is proposed to select the most important symbols(MIS).Then,in the completion phase,the weighted-selection strategy is applied to provide low overhead.The performance of the proposed scheme is analyzed and compared with the existing UEP online fountain scheme.Simulation results show that in terms of MIS and the least important symbols(LIS),when the bit error ratio is 10-4,the proposed scheme can achieve 85%and 31.58%overhead reduction,respectively.

Joint resource allocation for MIMO-OFDM video transmission systems with unequal error protection

To improve the performance of MIMO-OFDM video transmission systems on the limitation of wireless bandwidth and transmitting power,we propose an adaptive joint resource allocation algorithm with unequal error protection(UEP) based on joint source-channel coding(JSCC) according to H.264 video compression standard and RCPT channel coding.According to different thresholds of the average SNR of subchannels,the algorithm dynamically allocates the source coding parameters of original video data and the channel coding parameters of RCPT,which realizes UEP for the compressed video data of different importance.Through the bit and power allocation based on MQAM modulation and the subspace allocation based on beamforming technology for different subcarriers,an adaptive joint resource allocation making full use of space-frequency domain resources have been realized.The simulation results indicate that the algorithm improves the adaptability of video transmission systems in different wireless environments and the quality of video retrieval.

Feedback-based unequal error protection fountain code over device-to-device broadcast

To enhance encoding efficiency, an unequal error protection （UEP） broadcast scheme based on one additional feedback is proposed. Different from the equal probability selection for source packets in traditional fountain encoding, the proposed scheme calculates the packet loss ratio （PLR） according to the feedback results in systematic broadcast phase （SBP） and then optimizes the selection probability for source packets to guarantee higher level error protection for those source packets with larger PLRs. Thus the amount of unnecessarily redundant encoded packets during encoding broadcast phase （EBP） is decreased significantly. Numerical results show that the proposed scheme can recover 60% more packets than the traditional non-feedback broadcast scheme at the ex- pense of tolerably only one feedback procedure.

Study on Unequal Error Protection for Distributed Speech Recognition System

The unequal error protection （UEP） is applied in distributed speech recognition （DSR） system and three schemes are proposed. All of these three schemes are evaluated on the GSM simulating platform for recognizing mandarin digit strings and compared with the equal error protection （EEP） scheme. Experiments show that UEP can protect the data transmitted in DSR system more effectively, which results in a higher word accurate rate of DSR system.

Unequal error protection scheme for layered sources transmission over MIMO systems using spatial diversity and multiplexing technology

This paper proposes a hybrid scheme of the Alamouti coding and vertical bell labs layered space-time （V-BLAST） with the zero-forcing （ZF） receiver, which can achieve the unequal error protection （UEP） transmission in terms of the differences of importance in the layered sources. We analyze the tradeoff between spatial diversity and multiplexing in a mathematical manner, and prove the monotonic behavior of the crosspoint. Based on this scheme, we adopt V-BLAST to provide high data rates for the enhancement layer （EL） bitstreams, and adopt Alamouti coding to guarantee high reliability for the base layer （BL） bitstreams. Meanwhile, to improve the transmission reliability for the layered sources under the multiple-input multiple-output （MIMO） system with the limited-bandwidth and the total limited power, and to raise the frequency bandwidth efficiency, we take the power allocation considered in this proposed scheme. The simulation results show that the hybrid scheme has the average 1.9 dB and 1.3 dB gain in video peak signal-to-noise ratio （PSNR）, compared with the pure spatial diversity and pure spatial multiplexing scheme, respectively.

Unequal Error Protection Based on Expanding Window Fountain for Object-Based 3D Audio

This paper proposes an unequal error protection（UEP）coding method to improve the transmission performance of three-dimensional（3D）audio based on expanding window fountain（EWF）.Different from other transmissions with equal error protection（EEP）when transmitting the 3D audio objects.An approach of extracting the important audio object is presented,and more protection is given to more important audio object and comparatively less protection is given to the normal audio objects.Objective and subjective experiments have shown that the proposed UEP method achieves better performance than equal error protection method,while the bits error rates（BER）of the important audio object can decrease from 10^（–3） to 10^（–4）,and the subjective quality of UEP is better than that of EEP by 14%.

Genetic-optimization framework for SVC transmission based on partial cooperative communication

A genetic-optimization framework based on the partial cooperation communication protocol is proposed for scalable video coding (SVC) stream transmission under multi-relay amplify and forward cooperative networks. Unlike traditional cooperative transmission schemes, the transmission mode for each coded unit in this new protocol can be switched flexibly between direct transmission and cooperative transmission. Obviously, under this protocol, the bandwidth efficiency and transmission robustness can be balanced adaptively according to the priority level of coded units and wireless channel fading characteristics. Based on this, a well-known genetic optimization algorithm-differential evolution is exploited here to find the jointly optimal transmission modes, power allocation and unequal error protection (UEP) channel coding strategies to minimize the end to end reconstructed video distortion. Extensive simulation results show that, compared with classical optimal cooperative UEP transmission schemes, the proposed optimized transmission framework based on the partial cooperative protocol can bring significant peak-signal-to-noise-ratio (PSNR) gains for the reconstructed video in a variety of channel bandwidth, power budget and test sequences.

Channel Coding Techniques for VHF-Mobile Radio System and Its DSP Implementation

Two variable channel-coding schemes with unequal error protection （UEP） are proposed in terms of speech transmission over VHF-mobile radio system. These channel coding are separately based on rate-compatible punctured convolution （RCPC） code scheme and rate-compatible punctured turbo （RCPT） code scheme. With optimum puncturing designation and suitable scheme of rate matching, these two UEP schemes can achieve intra-class unequal error protection, which makes the protection for source bits with different importance more accurate. Its real time implementation based on a TMS320C6416 digital signal processor is also presented. The experimental results suggest that this method have reasonable system complexity and short processing delay.

An Enhanced LDPC Coded Partial Incremental Redundancy HARQ Scheme

An enhanced scheme is proposed for high code rate low density parity check （LDPC） coded partial incremental redundancy （PIR） hybrid automatic repeat request （HARQ）. It employs the unequal error protection （UEP） technique for incremental redundancy bits and uses the constellation rearrangement （CoRe） technique for information bits in retransmissions so as to reduce the reliability variances of all encoded bits after soft combining. Simulation results show that the proposed scheme applies to both regular LDPC and irregular LDPC cases and can efficiently improve frame error rate （FER） performance and throughput performance.