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

Full-Duplex Systems Using Multi-Reconfigurable Antennas

Full-duplex systems are expected to achieve 100% rate improvement over half-duplex systems if the self-interference signal can be significantly mitigated. In this paper, we propose the first full-duplex system utilizing Multi-Reconfigurable Antenna (MRA) with ?90% rate improvement compared to half-duplex systems. MRA is a dynamically reconfigurable antenna structure, that is capable of changing its properties according to certain input configurations. A comprehensive experimental analysis is conducted to characterize the system performance in typical indoor environments. The experiments are performed using a fabricated MRA that has 4096 configurable radiation patterns. The achieved MRA-based passive self-interference suppression is investigated, with detailed analysis for the MRA training overhead. In addition, a heuristic-based approach is proposed to reduce the MRA training overhead. The results show that at 1% training overhead, a total of 95dB self-interference cancellation is achieved in typical indoor environments. The 95dB self-interference cancellation is experimentally shown to be sufficient for 90% full-duplex rate improvement compared to half-duplex systems.Comment: Submitted to IEEE Transactions on Wireless Communication

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

An Application of an Information System via modern Topology

AbstractThis paper will discuss developing a new mathematical method through analysis ofinformation system where we deal with some ambiguity problems. We will representthis knowledge into one or more types of classes then we can use these classes to makea topology called modern Topology. After that we will compare the base of modernTopology with other basis after removing some attributes then we will decide the coreelements via the comparison. These elements will obviously be the true elements in the information system .we also will explain some analysis examples about diseases ,plantsand languages .we can show the core elements via methods of analysis .This paper shows how to use reduction of information through attribute reduction.After removing each attribute we must keep the basic properties of the system.This will inspire many to contribute to the cultivation of modern Topology in the field of mathematical instructure of modern approximations.partically rough set theory