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In this paper, we propose a novel method for correcting multiple errors in data packets, using the Cyclic Redundancy Check (CRC) syndrome present in low layers of protocol stacks. The proposed method generates the whole list of error patterns, leading to a received syndrome containing up to a given maximum number of errors. Our approach is table-free, is computationally efficient, and can instantly correct erroneous packets when the output list contains a single element. A performance study is conducted, and shows that the proposed approach outperforms existing ones in Bluetooth Low Energy (BLE) as it can correct all single-and double-error patterns as well as most triple-error cases when considering small payloads used in Internet of Things (IoT) applications.

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In this paper, we propose a methodology for estimating the statistics of the intercell interference power in the downlink of a multicellular network. We first establish an analytical expression for the probability law of the interference power when only Rayleigh multipath fading is considered. Next, focusing on a propagation environment where small-scale Rayleigh fading as well as large-scale effects, including attenuation with distance and lognormal shadowing, are taken into consideration, we elaborate a semi-analytical method to build up the histogram of the interference power distribution. From the results obtained for this combined small-and largescale fading context, we then develop a statistical model for the interference power distribution. The interest of this model lies in the fact that it can be applied to a large range of values of the shadowing parameter. The proposed methods can also be easily extended to other types of networks.

SoftCast-based linear video coding and transmission (LVCT) schemes have been proposed as a promising alternative to traditional video coding and transmission schemes in wireless environments. Currently, the performance of LVCT schemes is evaluated by means of traditional objective scores such as PSNR or SSIM. Nevertheless, since the compression is performed in a very different way from traditional coding schemes such as HEVC, visual artifacts are also quite different and deserve to be subjectively assessed. In this paper, we propose a subjective quality assessment of SoftCast, pioneer and standard of the LVCT schemes. This study aims to better understand the tradeoffs between the LVCT parameters that can be tuned to improve the quality. These parameters, including different GoP-sizes, Compression Ratios (CR) and Channel Signal-to-Noise Ratio (CSNR), are used to generate a dataset of 85 videos. A Double Stimulus Impairment Scale (DSIS) test is performed on the received videos to assess the perceived quality. Results show that the key characteristic of SoftCast, the linear relation between CSNR and PSNR, is also observed with the Mean-Opinion Scores (MOS), except at high CSNR where the quality saturates. In addition, Bjøntegaard model is used to quantify the trade-offs between CR, GoP-size and CSNR, depending on the intended application. Finally, the performance of objective metrics compared to the obtained MOS is evaluated. Results show that Multi-Scale SSIM (MS-SSIM), SSIM and Video Multimethod Assessment Fusion (VMAF) metrics offer the best correlation with the MOS values.

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In this paper, the concept of non-desynchronizing bits (NDBs) is defined in the context of H.264 video as a bit whose inversion does not cause desynchronization at the bitstream level or change the number of decoded macroblocks. We established that, on the whole, NDBs make up about a third (about 30%) of a bitstream, and that their flipping effect on visual quality is mostly insignificant. In most cases (90%), the PSNR value obtained when modifying an NDB is very close to the intact value. The performance of the proposed non-desync-based decoding framework, which retains a corrupted packet, under the condition of not causing desynchronization, has been compared to the JM-FC and a state-of-the-art concealment approach using the STBMA approach, and on average, respectively, provides 3.5 dB and 1.42 dB gain over them. Index Terms-video transmission, H.264, syntax elements, nondesynchronizing bit, concealment This work was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant.