Analysis and Planning Microwave Link to Established Efficient Wireless Communications
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A Review Paper on Microwave Transmission Using Reflector Antennas
International Journal of Scientific & Engineering Research Volume 8, Issue 10, October-2017 ISSN 2229-5518 251 A Review Paper on Microwave Transmission using Reflector Antennas Sandeep Kumar Singh [1],Sumi Kumari[2] Sr. Lecturer, Dept. of ECE, JBIT, Dehradun [1], Asst. Professor, Dept. of ECE, VGIET, Jaipur[2] [email protected][1] [email protected][2] Abstract: The conventional optimization problem of the beamed microwave energy transmission system is considered. The criterion of maximum efficiency of power intercept is parabolic function of distribution on the transmitting antenna. It is shown that under such a condition of amplitude distribution becomes more uniform than as the unconditional optimization. In this case, we can substantially increase the power radiated by the transmitting antenna losing the power intercept no more than 2%. Keywords: Parabolic Reflector Antenna, Radio Relay, Antenna Gain, Cassegrain Feed. I.INTRODUCTION limited to line of sight propagation; they cannot pass around hills or mountains as lower frequency radio waves can. Microwave radiation is generally defined as that electromagnetic radiation having wavelengths between radio waves and infrared III.ANTENNA radiation. Microwave radiation can be forced to travel in specially designed waveguides. Microwave radiation can be transmitted An antenna (or aerial) is an electrical device which converts through space or through the atmosphere in a microwave beam electric currents into radio waves, and vice versa. It is usually used from a microwave antenna and the microwave energy can be with a radio transmitter or radio receiver. In transmission, a radio collected with a microwave antenna. Microwave antennas are used transmitter applies an oscillating radio frequency electric current to for transmitting and receiving microwave radiation. -
Real Time C Band Link Budget Model Calculation
REAL TIME C BAND LINK BUDGET MODEL CALCULATION Item Type text; Proceedings Authors Rubio, Pedro; Fernandez, Francisco; Jimenez, Francisco Publisher International Foundation for Telemetering Journal International Telemetering Conference Proceedings Rights Copyright © held by the author; distribution rights International Foundation for Telemetering Download date 27/09/2021 23:53:15 Link to Item http://hdl.handle.net/10150/624184 REAL TIME C BAND LINK BUDGET MODEL CALCULATION Pedro Rubio, Francisco Fernandez, Francisco Jimenez Airbus D&S - Flight Test 1. ABSTRACT The purpose of this paper is to show the integration of the transmission gain values of a telemetry transmission antenna according to its relative position and integrate them in the C band link budget, in order to obtain an accuracy vision of the link. Once our C band link budget was fully performed to model our link and ready to work in real time with several received values (GPS position, roll, pitch and yaw) from the aircraft and other values from the Ground System (azimuth and elevation of the reception telemetry antenna), it was necessary to avoid a constant value of the transmitter antenna and estimate its values with better accuracy depending of the relative beam angles between the transmitter antenna and receiver antenna. Keeping in mind an aircraft is not a static telecommunication system it was necessary to have a real time value of the transmission gain. In this paper, we will show how to perform a real time link budget (C band). Keywords: Telemetry, Link Budget, C band, Real time, Dynamic gain 2. WHY C BAND AND REAL TIME – THE PREVIOUS SITUATION The new C Band migration involves the change of all telemetry chain and the challenge to cover the same area than in S Band with the same quality of service. -
Unit I Microwave Transmission Lines
UNIT I MICROWAVE TRANSMISSION LINES INTRODUCTION Microwaves are electromagnetic waves with wavelengths ranging from 1 mm to 1 m, or frequencies between 300 MHz and 300 GHz. Apparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, distributed circuit elements and transmission-line theory are more useful methods for design, analysis. Open-wire and coaxial transmission lines give way to waveguides, and lumped-element tuned circuits are replaced by cavity resonators or resonant lines. Effects of reflection, polarization, scattering, diffraction, and atmospheric absorption usually associated with visible light are of practical significance in the study of microwave propagation. The same equations of electromagnetic theory apply at all frequencies. While the name may suggest a micrometer wavelength, it is better understood as indicating wavelengths very much smaller than those used in radio broadcasting. The boundaries between far infrared light, terahertz radiation, microwaves, and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study. The term microwave generally refers to "alternating current signals with frequencies between 300 MHz (3×108 Hz) and 300 GHz (3×1011 Hz)."[1] Both IEC standard 60050 and IEEE standard 100 define "microwave" frequencies starting at 1 GHz (30 cm wavelength). Electromagnetic waves longer (lower frequency) than microwaves are called "radio waves". Electromagnetic radiation with shorter wavelengths may be called "millimeter waves", terahertz radiation or even T-rays. -
Repeaters, Satellites, EME and Direction Finding 23
Repeaters, Satellites, EME and Direction Finding 23 Repeaters his section was written by Paul M. Danzer, N1II. In the late 1960s two events occurred that changed the way radio amateurs communicated. The T first was the explosive advance in solid state components — transistors and integrated circuits. A number of new “designed for communications” integrated circuits became available, as well as improved high-power transistors for RF power amplifiers. Vacuum tube-based equipment, expensive to maintain and subject to vibration damage, was becoming obsolete. At about the same time, in one of its periodic reviews of spectrum usage, the Federal Communications Commission (FCC) mandated that commercial users of the VHF spectrum reduce the deviation of truck, taxi, police, fire and all other commercial services from 15 kHz to 5 kHz. This meant that thousands of new narrowband FM radios were put into service and an equal number of wideband radios were no longer needed. As the new radios arrived at the front door of the commercial users, the old radios that weren’t modified went out the back door, and hams lined up to take advantage of the newly available “commer- cial surplus.” Not since the end of World War II had so many radios been made available to the ham community at very low or at least acceptable prices. With a little tweaking, the transmitters and receivers were modified for ham use, and the great repeater boom was on. WHAT IS A REPEATER? Trucking companies and police departments learned long ago that they could get much better use from their mobile radios by using an automated relay station called a repeater. -
UNIT -1 Microwave Spectrum and Bands-Characteristics Of
UNIT -1 Microwave spectrum and bands-characteristics of microwaves-a typical microwave system. Traditional, industrial and biomedical applications of microwaves. Microwave hazards.S-matrix – significance, formulation and properties.S-matrix representation of a multi port network, S-matrix of a two port network with mismatched load. 1.1 INTRODUCTION Microwaves are electromagnetic waves (EM) with wavelengths ranging from 10cm to 1mm. The corresponding frequency range is 30Ghz (=109 Hz) to 300Ghz (=1011 Hz) . This means microwave frequencies are upto infrared and visible-light regions. The microwaves frequencies span the following three major bands at the highest end of RF spectrum. i) Ultra high frequency (UHF) 0.3 to 3 Ghz ii) Super high frequency (SHF) 3 to 30 Ghz iii) Extra high frequency (EHF) 30 to 300 Ghz Most application of microwave technology make use of frequencies in the 1 to 40 Ghz range. During world war II , microwave engineering became a very essential consideration for the development of high resolution radars capable of detecting and locating enemy planes and ships through a Narrow beam of EM energy. The common characteristics of microwave device are the negative resistance that can be used for microwave oscillation and amplification. Fig 1.1 Electromagnetic spectrum 1.2 MICROWAVE SYSTEM A microwave system normally consists of a transmitter subsystems, including a microwave oscillator, wave guides and a transmitting antenna, and a receiver subsystem that includes a receiving antenna, transmission line or wave guide, a microwave amplifier, and a receiver. Reflex Klystron, gunn diode, Traveling wave tube, and magnetron are used as a microwave sources. -
ECE145C: RF CMOS Communication Circuits and Systems Prof
ECE145C: RF CMOS Communication Circuits and Systems Prof. James Buckwalter © James Buckwalter 1 Organization • email: [email protected] • Lecture: Girvetz Hall 1112 8-9:15 • Faq: Piazza access code: ece145c (Gauchospace?) • Please allow 24-48 hour turnaround • Computing Lab: E1 • TAs – Di Li • Office Hours: T/Th 12-1, TBD • OH Location: ESB-2205C © James Buckwalter 2 Scope: ECE 145C should • refine fundamental understanding of RF circuits and systems to analyze modern wireless technology. • present a comprehensive understanding from devices to systems. • teach applications of RF CMOS as well as III-V • analyze RF transmitter/receiver architectures. Modern cellular and RF technologies are a mash-up of communication theory and devices. One needs to understand device limitations to understand communication system limits and vice versa. © James Buckwalter 3 Topics for our class • Propagation, Noise and Distortion Budgeting • Basics of Modulation / Cellular Standards • Receiver Filtering, Mixing, and Architectures • Power Amplifiers (Linear and Nonlinear): Output power and Efficiency • High-efficiency transmitters • RF Architectures (Putting it all together) © James Buckwalter 4 Lecture Topic Lecture Topic 1 (3/31) System Perspective: 2 (4/2) System Perspective: Link Budget Interference 3 (4/7) System Perspective: EVM 4 (4/9) System Perspective: Reciprocal Mixing 5 (4/14) Mixers (1) 6 (4/16) Mixers(2) 7 (4/21) Tunable Filters (I) 8 (4/23) Midterm 9 (4/28) Tunable Filters (II) 10 (4/30) RX Architectures: Mixer First 11 (5/5) RX Architectures: Direct 12 (5/7) Power Amplifiers: Classes Sampling 13 (5/12) Power Amplifiers: Classes 14 (5/14) Power Amplifiers: Spectral Regrowth 15 (5/19) Outphasing 16 (5/21) Outphasing Modulators Modulators…Transmitters 17 (5/26) Doherty Transmitters 18 (5/28) Doherty Transmitters 19 (6/1) Envelope Tracking 20 (6/3) Midterm Transmitters Reference Material • Razavi…for now. -
Path Loss and Link Budget
Path Loss and Link Budget Harald Welte <[email protected]> Path Loss A fundamental concept in planning any type of radio communications link is the concept of Path Loss. Path Loss describes the amount of signal loss (attenuation) between a receive and a transmitter. As GSM operates in frequency duplex on uplink and downlink, there is correspondingly an Uplink Path Loss from MS to BTS, and a Downlink Path Loss from BTS to MS. Both need to be considered. It is possible to compute the path loss in a theoretical ideal situation, where transmitter and receiver are in empty space, with no surfaces anywhere nearby causing reflections, and with no objects or materials in between them. This is generally called the Free Space Path Loss. Path Loss Estimating the path loss within a given real-world terrain/geography is a hard problem, and there are no easy solutions. It is impacted, among other things, by the height of the transmitter and receiver antennas whether there is line-of-sight (LOS) or non-line-of-sight (NLOS) the geography/terrain in terms of hills, mountains, etc. the vegetation in terms of attenuation by foliage any type of construction, and if so, the type of materials used in that construction, the height of the buildings, their distance, etc. the frequency (band) used. Lower frequencies generally expose better NLOS characteristics than higher frequencies. The above factors determine on the one hand side the actual attenuation of the radio wave between transmitter and receiver. On the other hand, they also determine how many reflections there are on this path, causing so-called Multipath Fading of the signal. -
Wireless Link Budget Analysis How to Calculate Link Budget for Your Wireless Network
Wireless Link Budget Analysis How to Calculate Link Budget for Your Wireless Network Whitepaper Radio Systems How far can it go and what will the throughput be? These are the two common questions that come up when designing a high speed wireless data link. There are several factors that may impact the performance of a radio system. Available and permitted output power, available bandwidth, receiver sensitivity, antenna gains, radio technology, and environmental conditions are some of the major factors that may impact system performance. For large scale network deployments, a detailed site survey and network design are highly recommended. This paper will attempt to provide the reader with an overview on how a link budget is calculated. Line-of-Sight (LOS) Link Budget To limit the scope of this paper, only line-of-sight links with sufficient Fresnel Zone clearance will be considered. The following equation shows the basic elements that need to considered when calculating a link budget: Received Power (dBm) = Transmitted Power (dBm) + Gains (dB) − Losses (dB) If the estimated received power is sufficiently large (typically relative to the receiver sensitivity), the link budget is said to be sufficient for sending data under perfect conditions. The amount by which the received power exceeds receiver sensitivity is FSPL (dB) called the link margin . Distance 900MHz 2.4GHz 5.8GHz 1km Free-Space Path Loss 91.53 100.05 107.72 2km 97.56 106.07 113.74 In a line-of-sight radio system, losses are mainly due to free-space path loss (FSPL ). FSPL is proportional to the square of the distance between the transmitter and 3km 101.08 109.60 117.26 receiver as well as the square of the frequency of the radio signal. -
AN1631-Simple Link Budget Estimation and Performance
AN1631 Simple Link Budget Estimation and Performance Measurements of Microchip Sub-GHz Radio Modules Usually, Sub-GHz channels are part of unlicensed Author: Pradeep Shamanna Industrial Scientific Medical (ISM) frequency bands. Microchip Technology Inc. Sub-GHz nodes generally target low-cost systems, with each node costing approximately 30% to 40% less compared to the advanced wireless systems and uses INTRODUCTION less stack memory. Many protocols such as IEEE ® The increased popularity of short range wireless in 802.15.4 based ZigBee (currently, the only protocol home, building and industrial applications with Sub- offering both 2.4 GHz and Sub-GHz versions in the GHz (<1 GHz) band requires the system designers to 868 MHz and 900 MHz bands), automation protocols, understand the methods, estimation, cost and trade-off cordless phones, Wireless Modbus, Remote Keyless in short range wireless communication. Apart from Entry (RKE), Tire Pressure Monitoring System (TPMS) considering the range estimation formula, it is good to and lot of proprietary protocols (including MiWi™), understand the wireless channel and propagation occupy this band. However, operation in the Sub-GHz environment involved with Sub-GHz. Generally, RF/ ISM band induces the radios to interfere with other wireless engineers perform a link budget while starting protocols utilizing the same spectrum which includes an RF design. The link budget considers range, threat from mobile phones, licensed cordless phones, transmit power, receiver sensitivity, antenna gains, and so on. frequency, reliability, propagation medium (which This application note describes a simple link budget includes the principles of physics linked to reflection, analysis, measurement and techniques to evaluate the diffraction and scattering of electromagnetic waves), range and performance of wireless transmission with and environment factors to accurately calculate the results, and uses developed models to estimate the performance of a Sub-GHz RF radio link. -
Range Calculation for 300Mhz to 1000Mhz Communication Systems
APPLICATION NOTE Range Calculation for 300MHz to 1000MHz Communication Systems RANGE CALCULATION Description For restricted-power UHF* communication systems, as defined in FCC Rules and Regula- tions Title 47 Part 15 Subpart C “intentional radiators*”, communication range capability is a topic which generates much interest. Although determined by several factors, communica- tion range is quantified by a surprisingly simple equation developed in 1946 by H.T. Friis of Denmark. This paper begins by introducing the Friis Transmission Equation and examining the terms comprising it. Then, real-world-environment factors which influence RF commu- nication range and how they affect a “Link Budget*” are investigated. Following that, some methods for optimizing RF-link range are given. Range-calculation spreadsheets, including the special case of RKE, are presented. Finally, information concerning FCC rules govern- ing “intentional radiators”, FCC-established radiation limits, and similar reference material is provided. Section 7. “Appendix” on page 13 includes definitions (words are marked with an asterisk *) and formulas. Note: “For additional information, two excel spreadsheets, RKE Range Calculation (MF).xls and Generic Range Calculation.xls, have been attached to this PDF. To open the attachments, in the Attachments panel, select the attachment, and then click Open or choose Open Attachment from the Options menu. For addi- tional information on attachments, please refer to Adobe Acrobat Help menu“ 9144C-RKE-07/15 1. The Friis Transmission Equation For anyone using a radio to communicate across some distance, whatever the type of communication, range capability is inevitably a primary concern. Whether it is a cell-phone user concerned about dropped calls, kids playing with their walkie- talkies, a HAM radio operator with VHF/UHF equipment providing emergency communications during a natural disaster, or a driver opening a garage door from their car in the pouring rain, an expectation for reliable communication always exists. -
Microwave Data Transmission Using Aml Techniques A. H
MICROWAVE DATA TRANSMISSION USING AML TECHNIQUES A. H. Sonnenschein P.E, I. Rabowsky, and W. C. Margiotta HUGHES AIRCRAFT COMPANY MICROWAVE COMMUNICATIONS PRODUCTS This paper discusses the characteristics and following effects: 1 -A shortening of permissible relative merits of some of the alternate signal amplifier cascades, 2- A major increase in the modulation methods which are employed to transmit cost of sophisticated headends to an extent that various forms of data and voice over AML microwave the cost of duplicating headends at various hubs systems. becomes prohibitive, and 3 - A further strain on limited frequency allocations. All the factors AML systems have during the past 10 years have intensified the necessity for the use of AML become widely accepted as the dominant means for systems in suburban as well as rural areas. Chan the local distribution of multiple video signals in nel capacities as high as 160 channels are fre the CATV industry. The reasons for this extensive quently necessary to accommodate all upstream as use of more than 20,000 video channel paths world well as downstream transmission requirements. wide are tabulated in Figures 1 and 2. In a nutshell, these reasons are that AML systems are More recently, various forms of data trans more cost effective, spectrum efficient, and reli mission requirements have been added to the prior able than any of the available alternatives. video and FM broadcast traffic requirements. Some of these new requirements are CATV related, for instance security alarm signals, subscriber addressable control signals, interactive service signals, etc. An even larger growth area however • ECONOMICAL FOR MULTIPLE CHANNELS is represented by opportunities for carrying sig e SPECTRUM EFFICIENT- HIGH CHANNEL CAPACITY nals for unrelated non-CATV entities on a leased • CABLE COMPATIBLE- VHF IN/OUT channel basis. -
Microwave Radio Transmission Design Guide
Microwave Radio Transmission Design Guide Second Edition page i Finals 06-17-09 10:39:14 For a listing of recent titles in the Artech House Microwave Library, turn to the back of this book. page ii Finals 06-17-09 10:39:14 Microwave Radio Transmission Design Guide Second Edition Trevor Manning page iii Finals 06-17-09 10:39:14 Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the U.S. Library of Congress. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library. ISBN-13: 978-1-59693-456-6 Cover design by Igor Valdman 2009 ARTECH HOUSE 685 Canton Street Norwood, MA 02062 All rights reserved. Printed and bound in the United States of America. No part of this book may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, or by any information storage and retrieval system, without permission in writing from the publisher. All terms mentioned in this book that are known to be trademarks or service marks have been appropriately capitalized. Artech House cannot attest to the accuracy of this information. Use of a term in this book should not be regarded as affecting the validity of any trademark or service mark. 10 987654321 page iv Finals 06-17-09 10:39:14 Contents Foreword xiii Preface xv 1 Introduction 1 1.1 History of Wireless Telecommunications 2 1.2 What Is Microwave Radio? 3 1.2.1 Microwave Fundamentals 3 1.2.2 RF Spectrum 4 1.2.3 Safety of Microwaves 5 1.2.4 Allocation