Sparse signal representation, sampling, and recovery in compressive sensing frameworks

Compressive sensing allows the reconstruction of original signals from a much smaller number of samples as compared to the Nyquist sampling rate. The effectiveness of compressive sensing motivated the researchers for its deployment in a variety of application areas. The use of an efficient sampling matrix for high-performance recovery algorithms improves the performance of the compressive sensing framework significantly. This paper presents the underlying concepts of compressive sensing as well as previous work done in targeted domains in accordance with the various application areas. To develop prospects within the available functional blocks of compressive sensing frameworks, a diverse range of application areas are investigated. The three fundamental elements of a compressive sensing framework (signal sparsity, subsampling, and reconstruction) are thoroughly reviewed in this work by becoming acquainted with the key research gaps previously identified by the research community. Similarly, the basic mathematical formulation is used to outline some primary performance evaluation metrics for 1D and 2D compressive sensing.Web of Science10850188500

Performance analysis of sphere packed aided differential space-time spreading with iterative source-channel detection

The introduction of 5G with excessively high speeds and ever-advancing cellular device capabilities has increased the demand for high data rate wireless multimedia communication. Data compression, transmission robustness and error resilience are introduced to meet the increased demands of high data rates of today. An innovative approach is to come up with a unique setup of source bit codes (SBCs) that ensure the convergence and joint source-channel coding (JSCC) correspondingly results in lower bit error ratio (BER). The soft-bit assisted source and channel codes are optimized jointly for optimum convergence. Source bit codes assisted by iterative detection are used with a rate-1 precoder for performance evaluation of the above mentioned scheme of transmitting sata-partitioned (DP) H.264/AVC frames from source through a narrowband correlated Rayleigh fading channel. A novel approach of using sphere packing (SP) modulation aided differential space time spreading (DSTS) in combination with SBC is designed for the video transmission to cope with channel fading. Furthermore, the effects of SBC with different hamming distances d(H,min) but similar coding rates is explored on objective video quality such as peak signal to noise ratio (PSNR) and also the overall bit error ratio (BER). EXtrinsic Information Transfer Charts (EXIT) are used for analysis of the convergence behavior of SBC and its iterative scheme. Specifically, the experiments exhibit that the proposed scheme of error protection of SBC d(H,min) = 6 outperforms the SBCs having same code rate, but with d(H,min) = 3 by 3 dB with PSNR degradation of 1 dB. Furthermore, simulation results show that a gain of 27 dB Eb/N0 is achieved with SBC having code rate 1/3 compared to the benchmark Rate-1 SBC codes.Web of Science2116art. no. 546

Robust mobile video transmission using DSTS-SP via three-stage iterative joint source-channel decoding

The last decade has witnessed a great growth in the number of cellular users, and consequently there is a prominent inclination towards wireless and mobile communication by the researchers. This research work considers the optimization of joint source and channel coding for the H.264/AVC (advanced video coding) stream. The source encoded video is serially transmitted using concatenated source bit coding (SBC) assisted by Rate-1 Precoder through a non-coherent differential space-time spreading (DSTS) scheme with multidimensional sphere packing (SP) modulation. More specifically, the Precoder is invoked as an intermediate encoder having an infmite impulse response which assists in the distribution of information across the decoders. Furthermore, the Precoder enhances the iterative decoding performance by splitting the overall system's iteration into inner and outer iterations. The H.264/AVC stream is highly compressed and yields residual redundancy which limits the iterative decoding performance. Therefore, for enhancing the performance of iteratively decoded systems, artificial redundancy is incorporated along the video bit stream using the SBC. Specifically, the iterative decoding provides better bit error ratio and also enhances the perceptual peak signal-to-noise ratio (PSNR) metric. Extrinsic information transfer (EXIT) chart analysis is done to measure the convergence behavior of our proposed system. The effect of minimum Hamming distance (d(H,min)) on the attainable performance of the joint source-channel coded video sequence is investigated. Quantitatively, our proposed DSTS - SP - Precoder - SBC[5 15] scheme having d(H,min) = 6 exhibits a noticeable improvement of about 22 dB gain at the PSNR degradation of 2 dB, against the DSTS - SP - Precoder - SBC[2 6]* benchmarker having d(H,min) = 1 for the correlated Rayleigh fading channel.Web of Science11art. no. 4

On the Performance of Wireless Video Communication Using Iterative Joint Source Channel Decoding and Transmitter Diversity Gain Technique

In this research work, we have presented an iterative joint source channel decoding- (IJSCD-) based wireless video communication system. The anticipated transmission system is using the sphere packing (SP) modulation assisted differential space-time spreading (DSTS) multiple input-multiple output (MIMO) scheme. SP modulation-aided DSTS transmission mechanism results in achieving high diversity gain by keeping the maximum possible Euclidean distance between the modulated symbols. Furthermore, the proposed DSTS scheme results in a low-complexity MIMO scheme, due to nonemployment of any channel estimation mechanism. Various combinations of source bit coding- (SBC-) aided IJSCD error protection scheme has been used, while considering their identical overall bit rate budget. Artificial redundancy is incorporated in the source-coded stream for the proposed SBC scheme. The motive of adding artificial redundancy is to increase the iterative decoding performance. The performance of diverse SBC schemes is investigated for identical overall code rate. SBC schemes are employed with different combinations of inner recursive systematic convolutional (RSC) codes and outer SBC codes. Furthermore, the convergence behaviour of the employed error protection schemes is investigated using extrinsic information transfer (EXIT) charts. The results of experiments show that our proposed Rate−2/3 SBC-assisted error protection scheme with high redundancy incorporation and convergence capability gives better performance. The proposed Rate−2/3 SBC gives about 1.5 dB Eb/N0 gain at the PSNR degradation point of 1 dB as compared to Rate−6/7 SBC-assisted error protection scheme, while sustaining the overall bit rate budget. Furthermore, it is also concluded that the proposed Rate−2/3 SBC-assisted scheme results in Eb/N0 gain of 24 dB at the PSNR degradation point of 1 dB with reference to Rate−1 SBC benchmarker scheme