All-Digital Self-interference Cancellation Technique for Full-duplex Systems

Full-duplex systems are expected to double the spectral efficiency compared to conventional half-duplex systems if the self-interference signal can be significantly mitigated. Digital cancellation is one of the lowest complexity self-interference cancellation techniques in full-duplex systems. However, its mitigation capability is very limited, mainly due to transmitter and receiver circuit's impairments. In this paper, we propose a novel digital self-interference cancellation technique for full-duplex systems. The proposed technique is shown to significantly mitigate the self-interference signal as well as the associated transmitter and receiver impairments. In the proposed technique, an auxiliary receiver chain is used to obtain a digital-domain copy of the transmitted Radio Frequency (RF) self-interference signal. The self-interference copy is then used in the digital-domain to cancel out both the self-interference signal and the associated impairments. Furthermore, to alleviate the receiver phase noise effect, a common oscillator is shared between the auxiliary and ordinary receiver chains. A thorough analytical and numerical analysis for the effect of the transmitter and receiver impairments on the cancellation capability of the proposed technique is presented. Finally, the overall performance is numerically investigated showing that using the proposed technique, the self-interference signal could be mitigated to ~3dB higher than the receiver noise floor, which results in up to 76% rate improvement compared to conventional half-duplex systems at 20dBm transmit power values.Comment: Submitted to IEEE Transactions on Wireless Communication

On Phase Noise Suppression in Full-Duplex Systems

Oscillator phase noise has been shown to be one of the main performance limiting factors in full-duplex systems. In this paper, we consider the problem of self-interference cancellation with phase noise suppression in full-duplex systems. The feasibility of performing phase noise suppression in full-duplex systems in terms of both complexity and achieved gain is analytically and experimentally investigated. First, the effect of phase noise on full-duplex systems and the possibility of performing phase noise suppression are studied. Two different phase noise suppression techniques with a detailed complexity analysis are then proposed. For each suppression technique, both free-running and phase locked loop based oscillators are considered. Due to the fact that full-duplex system performance highly depends on hardware impairments, experimental analysis is essential for reliable results. In this paper, the performance of the proposed techniques is experimentally investigated in a typical indoor environment. The experimental results are shown to confirm the results obtained from numerical simulations on two different experimental research platforms. At the end, the tradeoff between the required complexity and the gain achieved using phase noise suppression is discussed.Comment: Published in IEEE transactions on wireless communications on October-2014. Please refer to the IEEE version for the most updated documen

Self-Interference Cancellation with Nonlinear Distortion Suppression for Full-Duplex Systems

In full-duplex systems, due to the strong self-interference signal, system nonlinearities become a significant limiting factor that bounds the possible cancellable self-interference power. In this paper, a self-interference cancellation scheme for full-duplex orthogonal frequency division multiplexing systems is proposed. The proposed scheme increases the amount of cancellable self-interference power by suppressing the distortion caused by the transmitter and receiver nonlinearities. An iterative technique is used to jointly estimate the self-interference channel and the nonlinearity coefficients required to suppress the distortion signal. The performance is numerically investigated showing that the proposed scheme achieves a performance that is less than 0.5dB off the performance of a linear full-duplex system.Comment: To be presented in Asilomar Conference on Signals, Systems & Computers (November 2013

Improving musculoskeletal fitness and the performance enhancement of basketball skills through neuromuscular training program

The purpose of this study was to evaluate the effect of eight weeks of neuromuscular training program (NMTP) on musculoskeletal fitness and performance enhancement for basketball players. Twenty four male basketball players participated in this study and were divided into neuromuscular training group (NMT) or control group (CON). All players trained together as a team where NMT group participated 8 weeks of NMTP three times a week and CON group followed their regular protocol as guided by their coach. Musculoskeletal fitness was evaluated based on muscular strength, muscular endurance, and flexibility. Muscle strength was assessed by measuring grip strength and vertical jump test, muscular endurance was measured by push-up test and sit- up test, and flexibility was assessed using the sit-and-reach test. The basketball skills were assessed by passing test, speed spot shooting test, dribbling test, and defensive skill test. The subjects underwent all of the previously described tests before and after the training program. The results showed that the two groups demonstrated significant improvement, but the greater percentage of change is found in NMT group. The percentage of improvement in musculoskeletal fitness was ranged between 17% to 47% for NMT group versus 5% to 13% for CON, while ranged between 18% to 30% for NMT group versus 10% to 17% for CON group in skills performance. The study demonstrated that there is a significant effect of the NMTP which focused on core stability and lower extremity strength on musculoskeletal fitness and skills performance for young male basketball players

Comparison between autologous serum eye drops and punctal occlusion for treatment of dry eye syndrome

Background: Dried cornea condition characterized with mispreception regarding eye coat because of slit insufficiency otherwise unreasonable vanishing that makes harm to dried surfaces also visual shell which related to manifestations regarding visual inconvenience.Purpose: Comparing efficiency and safety of AS eye drops and Punctal occlusion for management of dry eye syndrome.Patients and Methods: A prospective study was conducted in, (Al-Hussein and Bab-Elsheryia hospitals), a sum of 40 eyes of 40 patients suffering from Dry eye (24 males, 16 females) were recruited in this study. The first group contain 20 eyes that undergo AS eye drops. The 2nd group contain 20 eyes that undergo Punctal occlusion.Results: The visual acuity in the first group before treatment was 3.5/9.3 ± 1.91/9.2 (mean ± standard deviation) and after treatment in the second visit was 5.25/10 ± 3.75/10 (P < 0.01) with standard improvement 2 Snellen lines. In the second group visual acuity before treatment was 2.85/9.1 ± 2.04/9.2 and after treatment in the second visit was 4.65/9.2 ± 4.37/10, the normal increase is 3 visual letters. The VA become better in both groups Conclusion: In summary, both two methods of management have similar efficiency in reducing discomfortable sensation in dry eyes, and almost have equivalent and improve in subjective symptoms. Punctual occlusion shows many benefits in conserving natural tears and enhancing tear quality and seemed to be better on tear film stabilization. AS eye drops and punctual occlusion improved BCV

Machine Learning Based IoT Adaptive Architecture for Epilepsy Seizure Detection: Anatomy and Analysis

A seizure tracking system is crucial for monitoring and evaluating epilepsy treatments. Caretaker seizure diaries are used in epilepsy care today, but clinical seizure monitoring may miss seizures. Monitoring devices that can be worn may be better tolerated and more suitable for long-term ambulatory use. Many techniques and methods are proposed for seizure detection; However, simplicity and affordability are key concepts for daily use while preserving the accuracy of the detection. In this study, we propose a versal, affordable noninvasive based on a simple real-time k-Nearest-Neighbors (kNN) machine learning that can be customized and adapted to individual users in less than four seconds of training time; the system was verified and validated using 500 subjects, with seizure detection data sampled at 178 Hz, the operated with a mean accuracy of (94.5%).Comment: Under review, 5 pages, 7 figures, 3 table

A Proposed Model for Predicting Employee Turnover of Information Technology Specialists Using Data Mining Techniques

This article proposes a data mining framework to predict the significant explanations of employee turn-over problems. Using Support vector machine, decision tree, deep learning, random forest, and other classification algorithms, the authors propose features prediction framework to determine the influencing factors of employee turn-over problem. The proposed framework categorizes a set of historical behavior such as years at company, over time, performance rating, years since last promotion, and total working years. The proposed framework also classifies demographics features such as Age, Monthly Income, and Distance from Home, Marital Status, Education, and Gender. It also uses attitudinal employee characteristics to determine the reasons for employee turnover in the information technology sector. It has been found that the monthly rate, overtime, and employee age are the most significant factors which cause employee turnover