Design of a novel hybrid intercarrier interference mitigation technique through wavelet implication in an OFDM system

This paper studies and analyzes the performance of the licensed-assisted access (LAA) scheme introduced by 3GPP in LTE Release 13, and adopted by 3GPP in LTE Release 14, which is called 3GPP LAA scheme for short. Considering the characteristics that the 3GPP LAA scheme is different from other LAA schemes and IEEE 802.11 distributed coordination function (DCF) protocol in WiFi systems, the 3GPP LAA scheme is modeled as a new two-dimensional discrete Markov model, and the collision probability and the channel occupancy utilization are further derived based on the proposed model. To more deeply analyze the performance of the 3GPP LAA scheme by comparisons, we also derive the expressions of the same performance indices for the linear backoff based LAA scheme proposed in this paper and the fixed contention window based LAA scheme mentioned in existing literatures. The simulation and numerical results prove the validity of the proposed Markov chain model, and also show that the 3GPP LAA scheme is the friendliest one to WiFi networks among the three LAA schemes, whereas its total channel occupancy utilization is the lowest when the number of LAA small base stations (SBSs) is little and that is the highest when large. However, the other two LAA schemes are still the graceful coexistence, which is defined as the scheme where the interference to WiFi users caused by LAA SBSs coexisting with them is not more than that caused by other WiFi APs replacing the LAA SBSs.

Performance Analysis of Licensed-Assisted Access to Unlicensed Spectrum in LTE Release 13

As a general and rigid mathematical tool, wavelet theory has found many applications and is constantly developing. This article reviews the development history of wavelet theory, from the construction method to the discussion of wavelet properties. Then it focuses on the design and expansion of wavelet transform. The main models and algorithms of wavelet transform are discussed. The construction of rational wavelet transform (RWT) is provided by examples emphasizing the advantages of RWT over traditional wavelet transform through a review of the literature. The combination of wavelet theory and neural networks is one of the key points of the review. The review covers the evolution of Wavelet Neural Network (WNN), the system architecture and algorithm implementation. The review of the literature indicates the advantages and a clear trend of fast development in WNN that can be combined with existing neural network algorithms. This article also introduces the categories of wavelet-based applications. The advantages of wavelet analysis are summarized in terms of application scenarios with a comparison of results. Through the review, new research challenges and gaps have been clarified, which will serve as a guide for potential wavelet-based applications and new system designs.

https://ieeexplore.ieee.org/ielx7/6287639/6514899/09785993.pdf

A Review of Wavelet Analysis and Its Applications: Challenges and Opportunities

As a general and rigid mathematical tool, wavelet theory has found many applications and is constantly developing. This article reviews the development history of wavelet theory, from the construction method to the discussion of wavelet properties. Then it focuses on the design and expansion of wavelet transform. The main models and algorithms of wavelet transform are discussed. The construction of rational wavelet transform (RWT) is provided by examples emphasizing the advantages of RWT over traditional wavelet transform through a review of the literature. The combination of wavelet theory and neural networks is one of the key points of the review. The review covers the evolution of Wavelet Neural Network (WNN), the system architecture and algorithm implementation. The review of the literature indicates the advantages and a clear trend of fast development inWNNthat can be combined with existing neural network algorithms. This article also introduces the categories of wavelet-based applications. The advantages of wavelet analysis are summarized in terms of application scenarios with a comparison of results. Through the review, new research challenges and gaps have been clarified, which will serve as a guide for potential wavelet-based applications and new system designs. 

Tertiary and quaternary recycling of thermoplastics by additive manufacturing approach for thermal sustainability

Orthogonal frequency division multiplexing (OFDM), a very promising technique that is leading the evolution in wireless mobile communication to sideline the bandwidth scarcity issue in spectrum allocation, is severely affected by the undesirable effects of the frequency offset error, which generates inter carrier interference (ICI) due to the Doppler shift and local oscillator frequency synchronization errors. There are many ICI cancellation techniques available in the literature, such as self-cancellation (SC), maximum likelihood estimation (MLE), and windowing, but they present a tradeoff between bandwidth redundancy and system complexity. In this study, a new energy-efficient, bandwidth-effective technique is proposed to mitigate ICI through cyclic prefix (CP) reuse at the receiver end. Unlike SC and MLE where the whole OFDM symbol data is transmitted in duplicate to create redundancy at the transmitter end, the proposed technique uses the CP data (which is only 20% of the total symbol bandwidth) to estimate the channel, and it produces similar results with a huge bandwidth saving. The simulation results show that the proposed technique has a significant improvement in error performance, and a comparative analysis demonstrates the substantial improvement in energy efficiency with high bandwidth gain. Therefore, it outperforms the legacy ICI cancellation schemes under consideration.

A novel energy-efficient ICI cancellation technique for bandwidth improvements through cyclic prefix reuse in an OFDM system

Orthogonal Frequency Division Multiplexing (OFDM), a most promising technique where multi-carrier modulation concept is implemented through splitting the signal into a number of signals, modulating each of these new signals to several orthogonal sub-carriers and combining the data received on the multiple channels at the receiver. Apart from delivering high spectrum efficiency, great channel robustness, immunity to impulse interferences, flexibility and easy equalization, OFDM is severely affected by undesirable effects of frequency offset errors (causes to generate inter carrier interface) due to Doppler shift in receiver frequency and Local oscillator frequency synchronization error. This paper describes some of the important ICI cancellation techniques, like Self Cancellation and Maximum Likelihood, and produces their performance comparative analysis with respect to BER and SNR. A new proposed technique is here by presented to further improve OFDM performance with varying Doppler shift error. The simulation results shows that proposed technique has significant improvements in the error performance and comparative analysis suggest that proposed technique has outperform legacy Self Cancellation and Maximum Likelihood ICI cancellation scheme with huge gain.

A novel hybrid ICI cancellation technique for OFDM optimization

Effects of irrigation water quality and NPK-fertigation levels on plant growth, yield and tuber size of potatoes in a sandy loam alluvial soil of semi-arid region of Indian Punjab

Last few years have delivered a huge boom in the field of research in Sentiment Analysis, totally on incredibly subjective textual content kinds like films or products evaluations. This research work design a feature selection technique with Bagged Random Forest classification to predict the sentiments of news articles. This work represents comparison among C4. 5, random forest algorithm, bagged random forest algorithm and proposed algorithm by taking various parameters into consideration. Results are evaluated on the basis of various attributes namely correctly classified instances, incorrectly classified instances, error comparison. The basis of this comparison was done by taking various parameters into light such as mean absolute error, root mean squared error, relative absolute error, root relative squared error, average true positive rate, average false positive rate, recall and F-measure. These new results have proved that the proposed technique is having better results than the previous one.

Harmanjeet Singh

Papers

Design of a novel hybrid intercarrier interference mitigation technique through wavelet implication in an OFDM system

A novel energy-efficient ICI cancellation technique for bandwidth improvements through cyclic prefix reuse in an OFDM system

A novel hybrid ICI cancellation technique for OFDM optimization

Effects of irrigation water quality and NPK-fertigation levels on plant growth, yield and tuber size of potatoes in a sandy loam alluvial soil of semi-arid region of Indian Punjab

An Efficient Approach for Sentiment Analysis using Data Mining Algorithms