The Statistical Evaluations of Transmission Characteristics, Limits of Ranges and Speeds of Transmission of Information Via the Pulsed Atmospheric Bistatic Optical Channels

2019 ◽  
pp. 97-104
Author(s):  
Mikhail V. Tarasenkov ◽  
Egor S. Poznakharev ◽  
Vladimir V. Belov
Keyword(s):  
Communication Systems ◽  
Estimation Algorithm ◽  
Transmission Characteristics ◽  
Radiation Beam ◽  
Optical Channels ◽  
The Monte Carlo Method ◽  
Wide Range ◽  
Transmission Of Information ◽  
Optical Axes ◽  
Visibility Range

The simulation program by the Monte Carlo method of pulse reactions of bistatic atmospheric aerosol-gas channels of optical-electronic communication systems (OECS) is created on the basis of the modified double local estimation algorithm. It is used in a series of numerical experiments in order to evaluate statistically the transfer characteristics of these channels depending on the optical characteristics of an atmosphere plane-parallel model for wavelengths λ = 0.3, 0.5, and 0.9 μm at a meteorological visibility range SM = 10 and 50 km. The results are obtained for a set of basic distances between the light source and the light receiver up to 50 km and for the angular orientations of the optical axes of a laser radiation beam and of the receiving system in a wide range of their values. The dependences of the pulse reactions maximum values over-the-horizon channels of the OECS on the variations of these parameters are established.

scholarly journals Correlation and Power Distribution of Intercore Crosstalk Field Components of Polarization-Coupled Weakly Coupled Single-Mode Multicore Fibres

Photonics ◽  
2021 ◽  
Vol 8 (6) ◽  
pp. 191
Author(s):  
José A. P. Morgado ◽  
Adolfo V. T. Cartaxo
Keyword(s):  
Power Distribution ◽  
Communication Systems ◽  
Single Mode ◽  
Coupled Mode ◽  
Weakly Coupled ◽  
Wide Range ◽  
Optical Communication Systems ◽  
The Mean ◽  
Distribution Of Power ◽  
Linear Propagation

The correlation and power distribution of intercore crosstalk (ICXT) field components of weakly coupled multicore fibers (WC-MCFs) are important properties that determine the statistics of the ICXT and ultimately impact the performance of WC-MCF optical communication systems. Using intensive numerical simulation of the coupled mode equations describing ICXT of a single-mode WC-MCF with intracore birefringence and linear propagation, we assess the mean, correlation, and power distribution of the four ICXT field components of unmodulated polarization-coupled homogeneous and quasi-homogeneous WC-MCFs with a single interfering core in a wide range of birefringence conditions and power distribution among the field components at the interfering core input. It is shown that, for homogeneous and quasi-homogeneous WC-MCFs, zero mean uncorrelated ICXT field components with similar power levels are observed for birefringence correlation length and birefringence beat length in the ranges of 0.5m,10m and 0.1m,10m, respectively, regardless of the distribution of power between the four field components at the interfering core input.

Pseudorandom Number Generators Based on Chaotic Dynamical Systems

2001 ◽  
Vol 08 (02) ◽  
pp. 137-146 ◽  
Author(s):  
Janusz Szczepański ◽  
Zbigniew Kotulski
Keyword(s):  
Dynamical Systems ◽  
Communication Systems ◽  
Initial Conditions ◽  
Pseudorandom Number ◽  
New Approach ◽  
Chaotic Dynamical Systems ◽  
Pseudorandom Number Generators ◽  
Transmission Of Information ◽  
Extreme Sensitivity ◽  
Contemporary Technology

Pseudorandom number generators are used in many areas of contemporary technology such as modern communication systems and engineering applications. In recent years a new approach to secure transmission of information based on the application of the theory of chaotic dynamical systems has been developed. In this paper we present a method of generating pseudorandom numbers applying discrete chaotic dynamical systems. The idea of construction of chaotic pseudorandom number generators (CPRNG) intrinsically exploits the property of extreme sensitivity of trajectories to small changes of initial conditions, since the generated bits are associated with trajectories in an appropriate way. To ensure good statistical properties of the CPRBG (which determine its quality) we assume that the dynamical systems used are also ergodic or preferably mixing. Finally, since chaotic systems often appear in realistic physical situations, we suggest a physical model of CPRNG.

scholarly journals Development of Electromagnetic Band Gap Structures in the Perspective of Microstrip Antenna Design

2013 ◽  
Vol 2013 ◽  
pp. 1-22 ◽  
Author(s):  
Md. Shahidul Alam ◽  
Norbahiah Misran ◽  
Baharudin Yatim ◽  
Mohammad Tariqul Islam
Keyword(s):  
Band Gap ◽  
Antenna Arrays ◽  
Communication Systems ◽  
Performance Enhancement ◽  
Microstrip Antennas ◽  
Microwave Devices ◽  
Electromagnetic Band Gap ◽  
Wide Range ◽  
High Efficient ◽  
Gap Characteristics

Electromagnetic band gap (EBG) technology has become a significant breakthrough in the radio frequency (RF) and microwave applications due to their unique band gap characteristics at certain frequency ranges. Since 1999, the EBG structures have been investigated for improving performances of numerous RF and microwave devices utilizing the surface wave suppression and the artificial magnetic conductor (AMC) properties of these special type metamaterial. Issues such as compactness, wide bandwidth with low attenuation level, tunability, and suitability with planar circuitry all play an important role in the design of EBG structures. Remarkable efforts have been undertaken for the development of EBG structures to be compatible with a wide range of wireless communication systems. This paper provides a comprehensive review on various EBG structures such as three-, two-, and one-dimensional (3D, 2D, and 1D) EBG, mushroom and uniplanar EBG, and their successive advancement. Considering the related fabrication complexities, implementation of vialess EBG is an attractive topic for microwave engineers. For microstrip antennas, EBG structures are used in diversified ways, which of course found to be effective except in some cases. The EBG structures are also successfully utilized in antenna arrays for reducing the mutual coupling between elements of the array. Current challenges and limitations of the typical microstrip antennas and different EBG structures are discussed in details with some possible suggestions. Hopefully, this survey will guide to increasing efforts towards the development of more compact, wideband, and high-efficient uniplanar EBG structures for performance enhancement of antenna and other microwave devices.

Study on Coupling of Step and Graded Index Single Mode Optical Fiber Considering the Transverse Misalignment

2020 ◽  
Vol 8 (2) ◽  
pp. 78-82
Author(s):  
Prosenjit Roy Chowdhury ◽  
◽  
Keyword(s):  
Optical Fiber ◽  
Communication Systems ◽  
Structural Parameters ◽  
Fractional Power ◽  
Single Mode ◽  
Spot Size ◽  
Fiber Coupling ◽  
Fundamental Parameters ◽  
Graded Index ◽  
Wide Range

"Advance design and day to day up-gradation of communication system is the requirement of international telecommunication. The optical communication systems involve the effective fiber coupling or splicing to meet the need of long communication channel. When the studies on both the intensive and extensive properties of optical fiber are exploring new research horizons, the effectiveness of such systems can be calibrated with transmission parameters like transmitted fractional power, which is a function of ‘spot size’ as well. Our study of fiber junctions based on fundamental parameters like wavelength, fiber profile index etc. has touched some unrevealed areas and explored some interesting results. The profile index of optical fiber has received less attention compared to other structural parameters of optical fiber but our study at important wavelengths for different profiles has shown that the less-used fiber profiles has some interesting premier outcomes, which can introduce some significant impact on optical fiber based system design and engineering. We have observed almost frequency or wavelength independent transmitted fractional power around the most used 1.55 micrometer wavelengths at some rarely used fiber profile index. Our study predicts the best and worst fiber profiles for transmitted fractional power (T ), at the same time, we have observed the fiber profile index independent region for a band of ‘T’ values. The reporting and its approach are found to be premier in this field. So, our work is reporting a comparison of effective fiber-to-fiber coupling, based on fiber profile index of different fibers. It is also giving a clear view of the wavelength dependency of effective fiber coupling for different fibers having wide range of graded fiber profiles."

PSK Transciever designing using SystemVue

2019 ◽  
Vol 3 (1) ◽  
Author(s):  
Deepali Chaurasia
Keyword(s):  
Signal Processing ◽  
System Integration ◽  
Communication Systems ◽  
Energy Savings ◽  
Electronic Devices ◽  
Physical Space ◽  
Electronic System ◽  
System Level ◽  
Complex Nature ◽  
Wide Range

Since, the industrial electronics is trending towards more compact components and system integration, innovative products offering greater flexibility, quality, safety, reliability, energy savings, wide range of connectivity with long operating lifetime. Now, Electronics is widely used in information processing, telecommunication and signal processing. Due to the complex nature of electronics theory, laboratory experimentation is an important part of development of electronic devices. These experiments are used to test or verify the proposed design and detect errors. Historically, electronics labs have consisted of electronic devices and equipment located in the physical space. Although in more recent years, the trend has been towards electronics lab simulation softwares and SystemVue is also one of them. SystemVue is a focussed electronic design automation (EDA) environment for electronic system-level (ESL) design. It enables system architects and algorithm developers to innovate the physical layer (PHY) of wireless and aerospace/defence communication systems and provide unique value to RF, DSP and FPGA/ASIC implementers. As a dedicated platform for ESL design and signal processing realization, SystemVue replaces general-purpose digital, analog and math environments. SystemVue “speaks RF”, cuts PHY development and verification time in half and connects to your mainstream EDA flow.

Wireless IEEE 802.11-Based Networking Approaches for Industrial Networked Systems

2013 ◽  
pp. 286-305
Author(s):  
Ricardo Moraes ◽  
Francisco Vasques
Keyword(s):  
Ieee 802.11 ◽  
Communication Systems ◽  
Networked Control Systems ◽  
Voice Over Ip ◽  
Next Generation ◽  
Medium Access ◽  
Communication Services ◽  
Access Protocol ◽  
Wide Range ◽  
New Applications

During the last few years, the demand for Real-Time (RT) communication has been steadily increasing due to a wide range of new applications. Remarkable examples are VoIP (Voice over IP) and Networked Control Systems (NCS). For such RT applications, the support of timely communication services is one of the major requirements. The purpose of this chapter is to survey the state-of-the-art on RT communication in CSMA-based networks and to identify the most suitable approaches to deal with the requirements imposed by next generation communication systems. This chapter focuses on one of the most relevant solutions that operate in shared broadcast environments, according to the CSMA medium access protocol, the IEEE 802.11 standard. From this survey, it becomes clear that traditional CSMA-based networks are not able to deal with the requirements imposed by next generation communication systems. More specifically, they are not able to handle uncontrolled traffic sources sharing the same broadcast environment.

scholarly journals Compact Rectifier Circuit Design for Harvesting GSM/900 Ambient Energy

Electronics ◽  
2020 ◽  
Vol 9 (10) ◽  
pp. 1614
Author(s):  
Surajo Muhammad ◽  
Jun Jiat Tiang ◽  
Sew Kin Wong ◽  
Amjad Iqbal ◽  
Mohammad Alibakhshikenari ◽  
...  
Keyword(s):  
Circuit Design ◽  
Communication Systems ◽  
Path Loss ◽  
Input Power ◽  
Wireless Communication Systems ◽  
Rf Power ◽  
Total Size ◽  
High Input Power ◽  
Wide Range ◽  
Rf Energy

In this paper, a compact rectifier, capable of harvesting ambient radio frequency (RF) power is proposed. The total size of the rectifier is 45.4 mm × 7.8 mm × 1.6 mm, designed on FR-4 substrate using a single-stage voltage multiplier at 900 MHz. GSM/900 is among the favorable RF Energy Harvesting (RFEH) energy sources that span over a wide range with minimal path loss and high input power. The proposed RFEH rectifier achieves measured and simulated RF-to-dc (RF to direct current) power conversion efficiency (PCE) of 43.6% and 44.3% for 0 dBm input power, respectively. Additionally, the rectifier attained 3.1 V DC output voltage across 2 kΩ load terminal for 14 dBm and is capable of sensing low input power at −20 dBm. The work presents a compact rectifier to harvest RF energy at 900 MHz, making it a good candidate for low powered wireless communication systems as compares to the other state of the art rectifier.

Design of Robust Quantizers for Low-Bit Analog-to-Digital Converters for Gaussian Source

2019 ◽  
Vol 28 (supp01) ◽  
pp. 1940002 ◽  
Author(s):  
Milan R. Dinčić ◽  
Zoran H. Perić ◽  
Dragan B. Denić ◽  
Zoran Stamenković
Keyword(s):  
Energy Consumption ◽  
Communication Systems ◽  
Mimo Systems ◽  
Automatic Gain Control ◽  
Gain Control ◽  
Analog To Digital Converters ◽  
Signal Power ◽  
Analog To Digital ◽  
Wide Range ◽  
Gaussian Source

This paper considers the design of robust logarithmic [Formula: see text]-law companding quantizers for the use in analog-to-digital converters (ADCs) in communication system receivers. The quantizers are designed for signals with the Gaussian distribution, since signals at the receivers of communication systems can be very well modeled by this type of distribution. Furthermore, linearization of the logarithmic [Formula: see text]-law companding function is performed to simplify hardware implementation of the quantizers. In order to reduce energy consumption, low-resolution quantizers are considered (up to 5 bits per sample). The main advantage of these quantizers is high robustness — they can provide approximately constant SNR in a wide range of signal power (this is very important since the signal power at receivers can vary in wide range, due to fading and other transmission effects). Using the logarithmic [Formula: see text]-law companding quantizers there is no need for using automatic gain control (AGC), which reduces the implementation complexity and increases the speed of the ADCs due to the absence of AGC delay. Numerical results show that the proposed model achieves good performances, better than a uniform quantizer, especially in a wide range of signal power. The proposed low-bit ADCs can be used in MIMO and 5G massive MIMO systems, where due to very high operating frequencies and a large number of receiving channels (and consequently a large number of ADCs), the reduction of ADC complexity and energy consumption becomes a significant goal.

Thermo-Optic Tuning Efficiency of Micro Ring Resonators on Low Thermal Resistance Silicon Photonics Substrates

2017 ◽  
Author(s):  
Shenghui Lei ◽  
Alexandre Shen ◽  
Ryan Enright
Keyword(s):  
Thermal Conductivity ◽  
Thermal Resistance ◽  
Thermal Performance ◽  
Silicon Photonics ◽  
Communication Systems ◽  
Device Fabrication ◽  
Ring Resonators ◽  
Wide Range ◽  
Soi Substrates ◽  
The Impact

Silicon photonics has emerged as a scalable technology platform for future optotelectronic communication systems. However, the current use of SiO2-based silicon-on-insulator (SOI) substrates presents a thermal challenge to integrated active photonic components such as lasers and semiconductor optical amplifiers due to the poor thermal properties of the buried SiO2 optical cladding layer beneath these devices. To improve the thermal performance of these devices, it has been suggested that SiO2 be replaced with aluminum nitride (AlN); a dielectric with suitable optical properties to function as an effective optical cladding that, in its crystalline state, demonstrates a high thermal conductivity (∼100× larger than SiO2 in current SOI substrates). On the other hand, the tuning efficiencies of thermally-controlled optical resonators and phase adjusters, crucial components for widely tunable lasers and modulators, are directly proportional to the thermal resistance of these devices. Therefore, the low thermal conductivity buried SiO2 layer in the SOI substrate is beneficial. Moreover, to further improve the thermal performance of these devices air trenches have been used to further thermally isolate these devices, resulting in up to ∼10× increase in tuning efficiency. Here, we model the impact of changing the buried insulator on a SOI substrate from SiO2 to high quality AlN on the thermal performance of a MRR. We map out the thermal performance of the MRR over a wide range of under-etch levels using a thermo-electrical model that incorporates a pseudo-etching approach. The pseudo-etching model is based on the diffusion equation and distinguishes the regions where substrate material is removed during device fabrication. The simulations reveal the extent to which air trenches defined by a simple etch pattern around the MRR device can increase the thermal resistance of the device. We find a critical under-etch below which no benefit is found in terms of the MRR tuning efficiency. Above this critical under-etch, the tuning efficiency increases exponentially. For the SiO2-based MRR, the thermal resistance increases by ∼7.7× between the un-etched state up to the most extreme etch state. In the unetched state, the thermal resistance of the AlN-based MRR is only ∼4% of the SiO2-based MRR. At the extreme level of under-etch, the thermal resistance of the AlN-based MRR is still only ∼60% of the un-etched SiO2-based MRR. Our results suggest the need for a more complex MRR thermal isolation strategy to significantly improve tuning efficiencies if an AlN-based SOI substrate is used.

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