Robust image transmission with OFDM over an AWGN channel

Arxiv preprint arXiv:1006.0840, 2010

This paper proposes new scheme for efficient rate allocation in conjunction with reducing peak-to-average power ratio (PAPR) in orthogonal frequency-division multiplexing (OFDM) systems. Modification of the set partitioning in hierarchical trees (SPIHT) image coder is proposed to generate four different groups of bit-stream relative to its significances. The significant bits, the sign bits, the set bits and the refinement bits are transmitted in four different groups. The proposed method for reducing the PAPR utilizes twice the unequal error protection (UEP), using the Read-Solomon codes (RS), in conjunction with bit-rate allocation and selective interleaving to provide minimum PAPR. The output bit-stream from the source code (SPIHT) will be started by the most significant types of bits (first group of bits). The optimal unequal error protection (UEP) of the four groups is proposed based on the channel destortion. The proposed structure provides significant improvement in bit error rate (BER) performance. Performed computer simulations have shown that the proposed scheme outperform the performance of most of the recent PAPR reduction techniques in most cases. Moreover, the simulation results indicate that the proposed scheme provides significantly better PSNR performance in comparison to well-known robust coding schemes.

— This paper proposes a system for transmission of image through OFDM system. To improve performance of system in terms of peak to average power ratio (PAPR) and Peak to signal noise ratio, Trigonometric Transforms such as DCT and DST are used.

This paper proposes new scheme for efficient rate allocation in conjunction with reducing peak-to-average power ratio (PAPR) in orthogonal frequency-division multiplexing (OFDM) system. Modification of the set partitioning in hierarchical trees (S PIHT) image coder is proposed to generate four different groups of bit-stream relative to its significances. The significant bits, the sign bits, the set bits and the refinement bits are transmitted in four different groups. The proposed method for reducing the PAPR utilizes twice the unequal error protection (UEP) using the ReadS olomon codes (RS) in conjunction with bit-rate allocation. The output bitstream from the source code (S PIHT) will be started by the most significant types of bits (first group of bits). The optimal unequal error protection (UEP) of the four groups is proposed. As a result, the proposed structure gives a significant improvement in bit error rate (BER) performance. Performed computer simulations have shown that the proposed scheme outperform the performance of most of the recent PAPR reduction techniques in most cases. Moreover, the simulation results indicate that the proposed scheme provides significantly better PS NR performance in comparison to well-known robust coding schemes.

Wireless Personal Communications, 2014

This paper presents a new technique for progressive image transmission over low-density parity-check coded orthogonal frequency division multiplexing (LDPC-OFDM) system. This technique adopts chaotic Baker map to improve the performance and reduce the peak-to-average power ratio (PAPR) of the OFDM signal. It helps improving the error resilient ability and also enhancing the efficiency of progressive image transmission over frequency selective fading channels. The proposed technique can effectively resist the fading impact of the frequency selective channels using simple frequency domain equalization. The proposed technique also utilizes the set partitioning in hierarchical trees as a source coding algorithm for the transmitted images. The distinctive feature of the proposed technique is that the transmitted data sequence has less data correlation, which leads to minimizing the PAPR. Simulation results show that the proposed technique improves the visual quality of the received images and reduces the PAPR of the OFDM signal as well.

Indonesian Journal of Electrical Engineering and Computer Science, 2022

Data transmission in orthogonal frequency division multiplexing (OFDM) system needs source and channel coding, the transmitted data suffers from the bad effect of large peak to average power ratio (PAPR). Source code and channel codes can be joined using different joined codes. Variable length error correcting code (VLEC) is one of these joined codes. VLEC is used in mat lab simulation for image transmission in OFDM system, different VLEC code length is used and compared to find that the PAPR decreased with increasing the code length. Several techniques are used and compared for PAPR reduction. The PAPR of OFDM signal is measured for image coding with VLEC and compared with image coded by Huffman source coding and Bose-Chaudhuri-Hochquenghem (BCH) channel coding, the VLEC code decreases the data transmitted size and keep the same level of PAPR reduction with respect to data coded by Huffman and BCH code when using PAPR reduction methods.

International Journal of Scientific & Technology Research, 2020

In the recent time, the speed in transmission of data over wireless communication channel is considered as the requirement in the communication world. This paper is focused on the transmission of images using Low-Density-Parity-Check (LDPC) coded Massive Multiple Input Multiple Output (MIMO) systems based on Orthogonal Frequency Division Multiplexing (OFDM) system over selective Rayleigh fading channel. The Quality objective measures and Bit Error Rate (BER) are used to examine the performance of the system. Simulation results prove that the proposed system enhances the performance of the recovered images. Also LDPC Coded Massive MIMO OFDM system gives an excellent BER performance.

Journal of theoretical and applied information technology, 2018

Orthogonal frequency division multiplexing (OFDM) is dependable in data transmission with high speed by the benefit of its robustness to multi-path fading, high data rate, and high spectral efficiency. OFDM is a multi-carrier modulation scheme. Synchronization is the major problems of the OFDM system. In this research, the power consumption was considering through a noisy channel when an image was transmitted in the OFDM system. To support the work, many features were tested such as minimizing the complexity with fast Fourier transforms/inverse fast Fourier transform (FFT/IFFT). The size of bandwidth (BW) play the main role and how its effect on the transmission and how its related to the FFT size (Nfft). The modulation type was also tested to see which one is the best for image transmitted. These types are phase shift keying (PSK) and quadrature amplitude modulation (QAM). In addition, signal to noise ratio (SNR) is one of the performances in OFDM system and consider one of the fac...

International Journal of Engineering Research and Technology (IJERT), 2015

https://www.ijert.org/image-transmission-using-dwt-technique-over-ofdm-system https://www.ijert.org/research/image-transmission-using-dwt-technique-over-ofdm-system-IJERTV4IS031038.pdf Abstrac tIn an OFDM system, due to channel fading, only a subset of carriers is usable for successful data transmission. With the help ofthe channel state information at the transmitter, it is possible to take a pro-active decision of mapping the description optimally onto the good subcarriers and discard it at the transmitter itself. In this paper, an image frame is compressed using DWT and the compressed data are mapped onto the OFDM system. Here, we have taken into consideration the one-bit channel state information that is available at the transmitter, informing whether the sub-channels are good or bad. In the case of a good sub-channel, the instantaneous received power should be greater than threshold P th. Otherwise; the lesser data values are discarded. By using MATLAB simulation, we can analysis the performance of our proposed scheme, in terms of energy saving where the received quality is in terms of peak signal to noise ratio.

IAEME PUBLICATION, 2013

In recent years, the speed in the transmission of audio and video data is a major concern. Thus, in this paper we present the results of the modulated OFDM (Orthogonal Frequency Division Multiplexing) still images that is based on the fast Fourier transform (FFT: Fast Fourier Transform) digital transmission. These results are obtained from a chain of communication developed in MATLAB. We evaluate the performance of the transmission system in terms of visual quality of the image reception (98% of the original image). We also obtain the different values of SNR, TEB, and other important parameters relying on the classic OFDM with a guard interval of time corresponding to 25% of the useful symbol period, and the modified OFDM, by just reducing that interval. The results are presented according to three patterns of M-PSK modulation frequency used in simulation. Namely: BPSK, QPSK and 16PSK and by extension, 256PSK modulation. It should be noted that convolutional coding is used to improve transmission quality.

Journal of Scientific Research, 2009

In this paper, we investigate the bit error rate (BER) performance of a concatenated low density parity check (LDPC) encoded orthogonal frequency-division multiplexing (OFDM) system on color image transmission. In FEC concatenated channel coding, the OFDM wireless communication system incorporates 1/2-rated convolution encoder under various digital modulations (QPSK, 8PSK, QAM, 8QAM, 16QAM and 32QAM) over an additative white gaussian noise (AWGN) and other fading (Raleigh and Rician) channels. Computer simulation results on BER demonstrate that the LDPC encoded OFDM system outperforms with QAM modulation technique as compared to other digital modulation scheme and the system is highly effective to combat inherent interferences under Rayleigh and Rician fading channels. The transmitted color image is found to have retrieved effectively under noisy and fading situations with implementation of sum-product algorithm, an effective iterative based LDPC decoding scheme. It has also been an...

International Journal of Future Generation Communication and Networking

Given the ability of orthogonal frequency division multiplexing (OFDM) to manage strict channels, it is a largely accepted multicarrier modulation method in current wireless communications, especially those with high data rate. In this study, an image was transmitted with considering the power consumption, which was received by the noisy channel of the OFDM systems. Many factors had been tested to support the work and to make the ideas specifically, the size of the fast Fourier transforms/inverse fast Fourier transform (FFT/IFFT) was tested to minimize complexity, which is the behavior of a system's process of transmitting and receiving data with less suffering. The bandwidth (BW) size was also considered, and who much it effects of the transmission process. The type of modulation, to choose the type of modulation, we use phase shift keying (PSK) and quadrature amplitude modulation (QAM) on the simulation and obtain a perfect modulation type of OFDM systems. Furthermore, signal-to-noise ratio (SNR), which is one of the main performance metrics of OFDM systems, was considered to determine its effect on the signal. Simulation results show, the effect of SNR on the bit error rate (BER) and the effect of the FFT number (nFFT) on the BER. Peak-to-power ratio (PAPR) is the main disadvantage of OFDM, thus our results take into account an effect of the nFFT on PAPR. The study focused on the BER with respect to SNR and to the nFFT, as well as the PAPR with respect to the nFFT. All simulation results were defined using a channel of additive white Gaussian noise (AWGN). Performance evaluation results were obtained through simulation using MATLAB.

2011

IMAGE TRANSMISSION OVER FADING CHANNELS USING RS-CC VERSUS LDPC CODING Erhan A. İnce, Edmond Nurellari, Leonardo O. Iheme Eastern Mediterranean University Electrical & Electronic Eng., Famagusta, TRNC, via Mersin 10 Turkey. Email: [email protected], [email protected], [email protected] ABSTRACT In this paper we present effective means of digital image transmission by means of Forward Error Correcting (FEC) schemes and Orthogonal Frequency Division Multiplexing (OFDM). ...

Third International Conference on Innovative Computing Technology (INTECH 2013), 2013

Transcoding is an inevitable need that is highly required for the current communication system like telemedicine, education, etc. However, it is not devoid of challenges that occur during retrieval end of format incompatibility. Apart from the massive research work in past on designing efficient transcoder architecture, quality of image resolution in wireless media is found to be quite challenging. Hence, this paper presents a novel algorithm that ensures transmission of a quality image file using pre-defined compression ratio and simulated over wireless standards e.g. OFDM. For ensuring quality delivery, the system uses simple and cost effective discrete wavelet transform that can maintain better resolution till the retrieval stage. Continued by quantization and entropy encoding, the system uses the design of JPEG2000 transcoder considering PSNR and BPP as the factor of evaluation

IEEE Transactions on Image Processing, 2000

In this paper, we propose a combined source/channel coding scheme for transmission of images over fading channels. The proposed scheme employs rate-compatible low-density parity-check codes along with embedded image coders such as JPEG2000 and set partitioning in hierarchical trees. The assignment of channel coding rates to source packets is performed by a fast trellis-based algorithm. We examine the performance of the proposed scheme over correlated and uncorrelated Rayleigh flat-fading channels with and without side information. Simulation results for the expected peak signal-to-noise ratio of reconstructed images, which are within 1 dB of the capacity upper bound over a wide range of channel signal-to-noise ratios, show considerable improvement compared to existing results under similar conditions. We also study the sensitivity of the proposed scheme in the presence of channel estimation error at the transmitter and demonstrate that under most conditions our scheme is more robust compared to existing schemes.

Wireless Personal Communications, 2015

In this paper, a proposed method for Peak-to-Average Power Ratio (PAPR) reduction of Orthogonal Frequency Division Multiplexing (OFDM) signals based on discrete transforms is presented for robust image communication. One of the discrete transforms such as discrete wavelet transform, discrete cosine transform, or discrete sine transform is applied to modify the OFDM signal at the output of the inverse fast Fourier transform stage. We first present the proposed OFDM system model with trigonometric transforms for PAPR reduction. Trigonometric transforms improve the performance of the OFDM system, and reduce the PAPR of the OFDM signal. Then, this scheme has been utilized for progressive image transmission using low-density parity-check coded OFDM over frequency-selective fading channels. The set partitioning in hierarchical trees algorithm is used for source coding of the images to be transmitted. The proposed scheme effectively resists the fading impact of frequency-selective fading channels using simple frequency-domain equalization. Simulation experiments are performed for a variety of multipath fading channels. We also propose a chaotic interleaving scheme based on the 2-D chaotic Baker map for PAPR reduction of OFDM signals. The distinctive feature of this scheme is that the transmitted signal has less correlation between samples, and hence the PAPR is minimized.