RESEARCH OF THE EFFICIENCY MULTISERVICE NETWORKS USING MIMO TECHNOLOGY

In the past, bilateral contralateral routing of signals (BICROS) amplification incorporated omnidirectional microphones on the transmitter and receiver sides and some models utilized noise reduction (NR) on the receiver side. Little research has examined the performance of BICROS amplification in background noise. However, previous studies examining contralateral routing of signals (CROS) amplification have reported that the presence of background noise on the transmitter side negatively affected speech recognition. Recently, NR was introduced as a feature on the receiver and transmitter sides of BICROS amplification, which has the potential to decrease the impact of noise on the wanted speech signal by decreasing unwanted noise directed to the transmitter side. The primary goal of this study was to examine differences in the reception threshold for sentences (RTS in dB) using the Hearing in Noise Test (HINT) in a diffuse listening environment between unaided and three aided BICROS conditions (no NR, mild NR, and maximum NR) in the Tandem 16 BICROS. A secondary goal was to examine real-world subjective impressions of the Tandem 16 BICROS compared to unaided. A randomized block repeated measures single blind design was used to assess differences between no NR, mild NR, and maximum NR listening conditions. Twenty-one adult participants with asymmetric sensorineural hearing loss (ASNHL) and experience with BICROS amplification were recruited from Washington University in St. Louis School of Medicine. Participants were fit with the National Acoustic Laboratories' Nonlinear version 1 prescriptive target (NAL-NL1) with the Tandem 16 BICROS at the initial visit and then verified using real-ear insertion gain (REIG) measures. Participants acclimatized to the Tandem 16 BICROS for 4 wk before returning for final testing. Participants were tested utilizing HINT sentences examining differences in RTS between unaided and three aided listening conditions. Subjective benefit was determined via the Abbreviated Profile of Hearing Aid Benefit (APHAB) questionnaire between the Tandem 16 BICROS and unaided. A repeated measures analysis of variance (ANOVA) was utilized to analyze the results of the HINT and APHAB. Results revealed no significant differences in the RTS between unaided, no NR, mild NR, and maximum NR. Subjective impressions using the APHAB revealed statistically and clinically significant benefit with the Tandem 16 BICROS compared to unaided for the Ease of Communication (EC), Background Noise (BN), and Reverberation (RV) subscales. The RTS was not significantly different between unaided, no NR, mild NR, and maximum NR. None of the three aided listening conditions were significantly different from unaided performance as has been reported for previous studies examining CROS hearing aids. Further, based on comments from participants and previous research studies with conventional hearing aids, manufacturers of BICROS amplification should consider incorporating directional microphones and independent volume controls on the receiver and transmitter sides to potentially provide further improvement in signal-to-noise ratio (SNR) for patients with ASNHL.

Introduction: The major requirement imposed to the systems of detection and prevention of malicious invasions into modern telecommunication infrastructures is the ability to find anomalies and invasion threats in real time. The complexity of this problem is in many respects caused by the incompleteness, discrepancy and diversity of the a priori knowledge about the distribution laws peculiar to the traffic of multiservice communication networks, as well as by the changing nature of malicious actions which make computer systems unsafe. Purpose: Increasing the speed and reliability of network traffic anomaly detection when the analyzed information is incomplete and highly heterogeneous. Results: A hybrid method and adaptive algorithms have been proposed for real-time anomaly detection in multiservice communication network traffic. The hybrid method unites the mechanism of non-identificational adaptation to the changing traffic parameters with the fuzzy logical inference used for regulating the algorithm parameters and for analyzing the output data. The adaptive algorithms are focused on combined implementation of modified stochastic approximation and pseudogradient search procedures. An experimental assessment has shown that the functional characteristics of the algorithms are close to the potentially achievable ones. Practical relevance: The developed method and algorithms can be implemented on available hardwaresoftware platforms on the basis of intellectual agent technology. Sharing them with already existing methods and algorithms of invasion detection can considerably increase the efficiency of information security systems in multiservice communication networks.

An analysis of the performance indicators multiservice telecommunication networks using the sixth technological order based on the NGN (Next Generation Network) architectural concept and future FN (Future Networks) networks was carried out to build high-performance steganographic systems with increased covert channels throughput, ensuring the achievement of a certain level information security. Comprehensive criteria for the efficiency the functioning steganographic systems are considered and the channel capacity of the steganosystem as a communication system with packet switching is selected. On the basis of the study, a new approach to constructing a method for evaluating complex indicators of the quality of steganographic communication during embedding and extracting hidden data is proposed. The quality of steganographic communication refers to the properties stegano communication to ensure the efficiency of the system, both timely and reliable transmission of messages. On the basis of the proposed approach, the effectiveness steganographic systems in the construction of covert channels for the transmission secret data transmitted over communication channels was studied. Taking into account the new entropy approach, a method for calculating the indicators of the latent throughput steganographic systems in packet-switched communication networks has been created. As a result of the study calculation method, important analytical expressions were obtained for evaluating complex indicators throughput steganographic systems, such as the throughput of covert channels, the maximum possible value of the performance of a binary source packets, the average packet transmission time with the proposed coding scheme, and the residual throughput of the communication channel.

In this study, an analysis of the performance of a digital communication system was conducted to improve the efficiency of the communication channel. The system was de- signed and evaluated in the MatLab/Simulink environment, specifically for the transmission of binary data in a multipath channel with static fading. One of the main advantages of this system is its ability to provide high noise immunity, even in the presence of noise, interference, and signal delays. The performance of the system was investigated in terms of bit error rate (BER) over both an additive white Gaussian noise (AWGN) channel and a multipath Rayleigh fading channel. The study also considered the impact of inter-symbol interference (ISI) and explored different parameters for a static channel, resembling a wireless LAN system based on IEEE 802.11 (as defined by Rec ITU-R M.1225). This study uses a solution to suppress inter-symbol interference using cascading coding (convolutional turbo codes with Reed Solo- mon code), Fast Fourier Transform (FFT) and Inverse Fast Fourier Transform (IFFT), amplifiers at the transmitter side and normalizer at the receiver side, by regulating the amplification ratios of transmitter and receiver sides. Modeling of a digital communication system for a wide-band fixed wireless LAN system (for Indoor office and Outdoor to indoor systems) has been performed. The modeling outcomes show that the applied method provides a good per- formance improvement in channels with ISI with static fading. The application of cascading coding (turbo code together with RS code), amplifiers, and FFT on the transmitter side, and IFFT on the receiver side will eliminate the effects of inter-symbol interference on digital signals in a multipath channel with static fading (as defined by Rec. ITU-R M.1225 for internal and external transmission systems) for wireless fixed systems.

Wireless power transfer technology features shorter power transmission distances in biomedical applications. This is a result of the small size of the implanted coils, biocompatible material conductivity, and the large distances between the receiving and transmitting coils. There have been numerous attempts to improve the power transfer efficiency across longer distances. Multiple coils, including 2-, 3-, 4-, and multi-layered coils, were previously considered. This study proposes a novel approach to achieve higher power transmission efficiency by integrating a single coil on the receiving side and three asymmetric coils on the transmitter side. As such, it delivers power to the sensor implanted within the coronary artery that monitors the blood pressure while introducing a uniquely shaped stent. The efficiency of power transmitted to the stent in its dual implanted forms, helical and zigzag helical, was examined as well, with the wireless power transmission system thereby analyzed at the 27 MHz Industrial Scientific Medical band operating frequency. For the four-coil technique, the power transmission efficiency at a distance of 25 mm between the receiver and transmitter sides by using biological human tissue as a medium between the transmission coils and the receiver stent can reach 56.42%, whereas other approaches show lower efficiencies: the three-coil method’s efficiency is 32.88%, the double-layer parallel method’s efficiency is 27.75%, the two-coil method’s efficiency is 24.76%, the triple-layer parallel method’s efficiency is 17.31%, the double-layer series method’s efficiency is 0.501%, and the triple-layer series method’s transmission efficiency is 0.092%. In addition, the suggested approach is demonstrated to be more efficient than prior designs with regard to the size of the implanted coils, which represent stents.

The Internet of Things [IoT] technology is recently used to autonomously collect and send data via a wireless channel. However, as the name implies, the primary requirement is Internet access, which is the main limitation for low-network locations. To send data from Sender to Receiver, the system employs LoRa Modules, mostly Ra-02, depending on the location. The sender can process the sensor data and send it over the personal network by utilizing LoRa (Long Range) Modules and the ESP8266. Solar panels can also be used for even reduced power usage. The data obtained will then be updated by the Real-Time Database on the Web Server through the Internet via Wi-Fi or GSM/GPRS Modem. Stored data may be accessed via a Web Application (Dynamic Website) on a mobile device. On both the transmitter and receiver sides, a low power OLED display is linked to provide real-time status. Due to the lack of power source on the transmitter side, we will power up utilizing a solar panel, charge controller, and battery. The solar panel will be 4V and the charge controller will be TP4056. The battery rating of 2200mAh is determined by the amount of power consumed.

When the data is transmitted through the channel, error mostly occurs in data which can be detected and corrected at the receiver side by using Hamming code. This technique is used now days in Wireless communication, in deep space communication etc, e.g. Fixed wireless broadband with high error rate where there is need of correction not only detection in the data. In this coding scheme the detection of data depend on the check/parity bits, these bits play a vital role in hamming code because they locate the position where the error has been occurred. These check bits are inserted into the data at specified position at the transmitter side.. But for the correction of data at receiver side without any need of retransmission, we need to find the value of check bits. And to find theses bits we design a matrix which gives us the values of check bits (0.1) with the help of data bits. Normally these bits can be found by using Ex-Or gate[16]. In this paper I have found these bits using another logic that is AND-OR logic., for the sake of convenience and knowledge. When the data is received at the receiver side and suppose error is occurred than at the receiver side again we need to find the check bits by repeating the process at transmitter side. Than will compare the check bits at transmitter and receiver side using a new logic, that is AND-OR logic, which will locate the position of error. And the data can be recovered easily without need of retransmission of data.

Today, the use of these methods as hybrids has provided the motivation to be a solution to important problems, since the existing methods are insufficient at some points in ensuring the security of personal data. In data security, the inability to decrypt and decrypt the signal to be encrypted retrospectively has always been the subject of research in terms of privacy. At this point, it was preferred to use the electrocardiography (ECG) signal, which is a signal that shows the vital signs of the human body and is also difficult to copy. In the study, firstly, the emulator circuit was obtained by using the mathematical model of the ECG signal. With this obtained signal, the audio signals are masked. The audio signal masked on the transmitter side and the signals providing synchronization were transmitted to the receiver side over a single channel using the frequency division multiplexing (FDM) method. Then, the sliding mode control (SMC) method was chosen for the synchronization of the ECG emulator circuits on the receiver and transmitter side. Histogram, spectral, mean square error (MSE), peak signal to noise ratio (PSNR), key space and key sensitivity, NSCR (number of sample change rate), UACI (unified average changing intensity) and PESQ (perceptual evaluation of speech quality) analyses were used to check the accuracy of the system. These analyses showed that the ECG encoding method has faster unit change, reduces synchronization time, minimizes losses and improves the security of the masked signal compared to other methods sent from two channels. Finally, use of an arrhythmia ECG signal for the synchronization signal on both the transmitter and receiver sides, the synchronization of this signal with the SMC method and the testing of a live audio recording in addition to the conversation, distinguishes the study from other existing studies and reveals its originality.

In orthogonal frequency division multiplexing (OFDM) system, the time variation of a wireless channel destroys orthogonality among the sub-carriers, and this induces inter-carriers interference (ICI) and degrades system performance severely in mobile environment. In this paper, a new method of ICI cancellation based on delay diversity (DD) was proposed, which provides a way to mitigate the negative effect from the time variation of the wireless paths, thus improve the system performance greatly. The new method was called time-domain self-interference cancellation (TDSIC) algorithm, which is different from other existing methods, such as frequency-domain method. In a cyclically extended OFDM system, the fading characteristics of extended OFDM symbols with different cyclic delay are different with each other, so in our TDSIC method, a new diversity collection scheme at the receiver end is proposed, which can be used to improve the system performance by suppressing ICI through selecting appropriate parameters. Moreover, the cyclically extended OFDM symbol at the transmitter side and diversity collection with different delay added OFDM symbols at the receiver side are used in the TDSIC method with the tradeoff of time-expense, so the well-known fixed delay for symbol at the transmitter side may be detected by the receiver side through estimating several parameters of wireless channels. In summary, the key of the TDSIC method is to improve the system performance with the cost of time. Based on performance analysis, simulation has proved that TDSIC may effectively improve the performance of the time-variant wireless channel.

For an orthogonal frequency-division multiplexing system with pilot-symbol aided channel estimation, we compare the measured bit error ratio to the theoretical bit error probabil- ity. In order to measure mobile physical systems, we utilize the Vienna Wireless Testbed which has been augmented by a rotation wheel unit. The analytical solution assumes Rayleigh fading, additive Gaussian noise, and an arbitrary linear interpolation method to estimate the unknown channel taps. Our measurements confirm our assumptions and demonstrate convincingly that our theoretical expressions accurately model the true physical behavior, even for speeds of up to 100 km/h. I. INTRODUCTION Nowadays, most wireless communication standards (DAB, LTE, WIFI 802.11) employ Orthogonal Frequency Division Multiplexing (OFDM) as their modulation technique. While we have a good knowledge of what to expect in coherent transmissions over wireless channels in idealistic setups, the implications of practical systems are by far not so well understood. In particular high speed scenarios as they appear in car/train to infrastructure communications by LTE require a solid understanding of the transmission chain. Coherent trans- mission requires channel knowledge which typically comes by estimation based on training or so-called pilot symbols, i.e., known symbols at transmitter and receiver side. Pilot-symbol- Aided Channel Estimation (PACE) is usually considered in this context whereby the channel at data positions is estimated by interpolation. The optimal linear interpolation in terms of Minimum Mean Squared Error (MMSE) was derived in (1). However, an MMSE solution requires a-priori knowledge of the channel statistics and a matrix inversion. This motivated other authors to investigate different interpolation methods e.g., spline (2), 2D Deslauriers-Dubuc (3) and 2D low-pass (4). As a comparison measure the Bit Error Ratio (BER) was obtained through Monte Carlo simulations. Such simulations require a long simulation time and do not offer analytical insights. This recently motivated us to derive an analytical Bit Error Probability (BEP) expression for arbitrary linear interpolation methods (5) which can, for example, be used to find an improved pilot pattern design or to determine the optimal trade-off between pilot and data symbol power (6). Mobile wireless communication channels are characterized by time-varying multipath propagation (7), i.e., due to multiple scatterers, the electromagnetic signal can propagate along several different paths which causes frequency-selectivity and time-selectivity. The first can be combated by inserting a cyclic prefix while the latter leads to Inter-Carrier Interference (ICI)

Abstract: In SISO (single input and single output) system, refers to have only one input and one output. Here only one antenna is used at receiver and transmitter side. SISO are relatively simple to design and implement. They are of low cost and used in wide range of applications. However, SISO systems are poor in performance and deliver low data rate. So we’ll prefer MIMO (multiple input and multiple output) over SISO as it gives better spectral efficiency, improved reliability and good coverage. In MIMO we use multiple antennas at transmitter and receiver side which is known as Spatial Multiplexing(SM) which enhances the data rate. In the paper the performance of spatial combining MIMO system is analysed. Matlab used for simulation.

The security of keys in quantum cryptography is based on fundamental quantum mechanical exclusions (the exclusion of cloning and copying of nonorthogonal quantum states. The physical type of a quantum object that carries information (photon, electron, atom, etc.) is insignificant; only its state vector is important. In relativistic quantum cryptography for open space, both the time of the information carrier (photon that propagates with the extremely allowable velocity in a vacuum) and its quantum state are of fundamental importance. Joint fundamental constraints that are dictated by both special relativity and quantum mechanics on the discrimination of nonorthogonal quantum states allow one to formulate fundamentally new key distribution protocols that are stable against any attacks on a key and guarantee the security of keys for a nonstrictly single-photon source and any losses in the communication channel. Although this protocol is a real-time protocol in the Minkowski space-time, where the attack to the communication channel is detected by the delay of eavesdropper measurement results, the protocol does not require clock synchronization on the transmitter and receiver sides.

The primary goal of this project was educational: to demonstrate Software Defined Radio based prototyping using Visual C++ Express and Code Composer Studio. More specifically an IEEE802.11a Phy [1] compliant baseband processor was written in C++ and a radio link demonstrated “live” using a standard PCand the DSK6713 kit from Spectrum Digital [2] for baseband processing at the receiver and transmitter side respectively. To reduce costs without loss of educational value (the algorithms remains the same), the bandwidth was scaled down from 20MHz to 6 kHz to be able to utilize cheap narrowband COTS RF frontends operating at an intermediate frequency of only 12 kHz at the transmitter and receiver sides. This was easily achieved by just reducing the OFDM symbol rate by a suitable factor. The development process is described in detail, emphasizing development tricks to facilitate debugging of this kind of complex baseband processing. For educational purposes some other simpler waveforms was implemented as well.

The article presents the results of the analysis of noise immunity of analog EM nodes for the example of amplifying devices in integrated design, presents the results of noise immunity analysis, presents its estimates and recommendations on noise-proof design of amplifying nodes, substantiates the expediency of using two fundamentally different characteristics of noise immunity - the effectiveness of protection and noise immunity

The transmission of images over wireless channels is increasing with advances in wireless communication technologies. However, ensuring secure and efficient transmission is a major challenge because intrusive receivers may be present, wireless channels have high bit error rates and limited bandwidth. This paper proposes a wireless transmission scheme for encrypted images to establish reliable and robust communications. The proposed scheme comprises on the transmitter side, encryption, compression, channel coding and modulation, and their inverse processes at the receiver. The Discrete Wavelet Transformed and the Huffman coding are employed for image compression, whereas convolutional coding is used as a technique for error correction. The system is implemented with the USRP NI-2920 modules and LabVIEW Communications 2.0 software, allowing the transmission of encrypted images both in real and simulated environments. The results show that the proposed system is robust and efficient against channel degradation.