Lab 3: Modulation and Detection
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Properties of Angle Modulation
Properties of Angle Modulation Properties of Angle Modulation Reference: Sections 4.2 and 4.3 of Professor Deepa Kundur S. Haykin and M. Moher, Introduction to Analog & Digital University of Toronto Communications, 2nd ed., John Wiley & Sons, Inc., 2007. ISBN-13 978-0-471-43222-7. Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 1 / 25 Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 2 / 25 Angle Modulation carrier I Phase Modulation (PM): θi (t) = 2πfc t + kpm(t) 1 dθ (t) k dm(t) f (t) = i = f + p message i 2π dt c 2π dt sPM (t) = Ac cos[2πfc t + kpm(t)] amplitude modulation I Frequency Modulation (FM): Z t θi (t) = 2πfc t + 2πkf m(τ)dτ 0 phase 1 dθ (t) modulation f (t) = i = f + k m(t) i 2π dt c f Z t sFM (t) = Ac cos 2πfc t + 2πkf m(τ)dτ 0 frequency modulation Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 3 / 25 Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 4 / 25 carrier carrier message message amplitude amplitude modulation modulation phase phase modulation modulation frequency frequency modulation modulation Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 5 / 25 Professor Deepa Kundur (University of Toronto) Properties of Angle Modulation 6 / 25 4.2 Properties of Angle Modulation 4.2 Properties of Angle Modulation Constancy of Transmitted Power Constancy of Transmitted Power: AM 1 I Consider a sinusoid g(t) = Ac cos(2πf0t + φ) where T0 = or T0f0 =1. f0 I The power of g(t) (over a 1 ohm resister) is defined as: Z T0=2 Z T0=2 1 2 1 2 2 P = g (t)dt = Ac cos (2πf0t + φ)dt T0 −T0=2 T0 −T0=2 2 Z T0=2 Ac 1 = [1 + cos(4πf0t + 2φ)] dt T0 −T0=2 2 2 T0=2 Ac sin(4πf0t + 2φ) = t + 2T 4f 0 0 −T0=2 A2 T −T sin(4πf T =2 + 2φ) − sin(−4πf T =2 + 2φ) = c 0 − 0 + 0 0 0 0 2T0 2 2 4πf0 2 2 Ac sin(2π + 2φ) − sin(−2π + 2φ) Ac = T0 + = 2T0 4πf0 2 I Therefore, the power of a sinusoid is NOT dependent on f0, just its envelop Ac . -
Degree Project
Degree project Performance of MLSE over Fading Channels Author: Aftab Ahmad Date: 2013-05-31 Subject: Electrical Engineering Level: Master Level Course code: 5ED06E To my parents, family, siblings, friends and teachers 1 Research is what I'm doing when I don't know what I'm doing1 Wernher Von Braun 1Brown, James Dean, and Theodore S. Rodgers. Doing Second Language Research: An introduction to the theory and practice of second language research for graduate/Master's students in TESOL and Applied Linguistics, and others. OUP Oxford, 2002. 2 Abstract This work examines the performance of a wireless transceiver system. The environment is indoor channel simulated by Rayleigh and Rician fading channels. The modulation scheme implemented is GMSK in the transmitter. In the receiver the Viterbi MLSE is implemented to cancel noise and interference due to the filtering and the channel. The BER against the SNR is analyzed in this thesis. The waterfall curves are compared for two data rates of 1 M bps and 2 Mbps over both the Rayleigh and Rician fading channels. 3 Acknowledgments I would like to thank Prof. Sven Nordebo for his supervision, valuable time and advices and support during this thesis work. I would like to thank Prof. Sven-Eric Sandstr¨om.Iwould also like to thank Sweden and Denmark for giving me an opportunity to study in this education system and experience the Scandinavian life and culture. I must mention my gratitude to Sohail Atif, javvad ur Rehman, Ahmed Zeeshan and all the rest of my buddies that helped me when i most needed it. -
Bit & Baud Rate
What’s The Difference Between Bit Rate And Baud Rate? Apr. 27, 2012 Lou Frenzel | Electronic Design Serial-data speed is usually stated in terms of bit rate. However, another oft- quoted measure of speed is baud rate. Though the two aren’t the same, similarities exist under some circumstances. This tutorial will make the difference clear. Table Of Contents Background Bit Rate Overhead Baud Rate Multilevel Modulation Why Multiple Bits Per Baud? Baud Rate Examples References Background Most data communications over networks occurs via serial-data transmission. Data bits transmit one at a time over some communications channel, such as a cable or a wireless path. Figure 1 typifies the digital-bit pattern from a computer or some other digital circuit. This data signal is often called the baseband signal. The data switches between two voltage levels, such as +3 V for a binary 1 and +0.2 V for a binary 0. Other binary levels are also used. In the non-return-to-zero (NRZ) format (Fig. 1, again), the signal never goes to zero as like that of return- to-zero (RZ) formatted signals. 1. Non-return to zero (NRZ) is the most common binary data format. Data rate is indicated in bits per second (bits/s). Bit Rate The speed of the data is expressed in bits per second (bits/s or bps). The data rate R is a function of the duration of the bit or bit time (TB) (Fig. 1, again): R = 1/TB Rate is also called channel capacity C. If the bit time is 10 ns, the data rate equals: R = 1/10 x 10–9 = 100 million bits/s This is usually expressed as 100 Mbits/s. -
Application of 4K-QAM, LDPC and OFDM for Gbps Data Rates Over HFC Plant David John Urban Comcast
Application of 4K-QAM, LDPC and OFDM for Gbps Data Rates over HFC Plant David John Urban Comcast Abstract Higher spectral density requires mapping more bits into a symbol at the expense of a This paper describes the application of higher signal to noise ratio (SNR) threshold. 4096-QAM, low density parity check codes The new physical layer will map 12 bits per (LDPC), and orthogonal frequency division symbol on the downstream compared to the 8 multiplexing (OFDM) to transmission over a bits per symbol used in DOCSIS 3.0. 4K- hybrid fiber coaxial cable plant (HFC). These QAM (or 4096-QAM) is a modulation techniques enable data rates of several Gbps. technique that has 4,096 points in the constellation diagram and each point is A complete derivation of the equations mapped to 12 bits. The new physical layer used for log domain sum product LDPC will map 10 bits per symbol using 1024-QAM decoding is provided. The reasons for (or 1K-QAM) on the upstream compared to 6 selecting OFDM and 4K-QAM are described. bits per symbol with 64-QAM used in Analysis of performance in the presence of DOCSIS 3.0. noise taken from field measurements is made. INCREASING SPECTRAL EFFICIENCY INTRODUCTION The three key methods for increasing the A new physical layer is being developed for spectral efficiency of the HFC plant in the transmission of data over a HFC cable plant. new physical layer are LDPC, OFDM and The objective is to increase the HFC plant 4K-QAM. LDPC is a very efficient coding capacity. -
A Measurement Instrument for Fault Diagnosis in Qam-Based Telecommunications
12th IMEKO TC4 International Symposium Electrical Measurements and Instrumentation September 25−27, 2002, Zagreb, Croatia A MEASUREMENT INSTRUMENT FOR FAULT DIAGNOSIS IN QAM-BASED TELECOMMUNICATIONS Pasquale Arpaia(1), Luca De Vito(1,2), Sergio Rapuano(1), Gioacchino Truglia(1,2) (1) Dipartimento di Ingegneria, Università del Sannio, piazza Roma, Benevento, Italy (2) Telsey Telecommunications, viale Mellusi 68, Benevento, Italy Abstract − A method for diagnosing faults in Some techniques for classifying automatically the main communication systems based on QAM (Quadrature faults on QAM modulation via the constellation diagram Amplitude Modulation) modulation scheme is proposed. were proposed. The approach followed in [4] is based on a The most relevant faults affecting this modulation have been Wavelet Network (WN). This method provides very good observed and modelled. Such faults, individually and results on simulated and actual signals. combined, are classified and estimated by analysing the Another method classifies the faults through an image- statistical moments of the received symbols. Simulation and processing approach [5]. The constellation diagram is experimental results of characterisation and validation digitised, then the obtained image is compared with some highlight the practical effectiveness of the proposed method. fault models, by using a correlation method, and a similarity score is provided. Keywords: Fault diagnosis, telecommunication, testing, However, both the WN- and the image processing-based QAM. methods can recognize and eventually measure only the dominating fault, and can not recognize the simultaneous 1. INTRODUCTION presence of several faults. In this paper, a diagnostics method, based on analytical Quadrature Amplitude Modulation (QAM) is an estimation of the statistical moments of the received symbol attractive method for transmitting two data streams in distribution, is proposed for QAM-modulation. -
CE-OFDM Thesis
Design and Implementation of a Constant Envelope OFDM Waveform in a Software Defined Radio Platform Amos Vershima Ajo Jr. Thesis submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Master of Science in Electrical Engineering Carl B. Dietrich, Chair A. A. (Louis) Beex, Chair Allen B. MacKenzie May 5, 2016 Blacksburg, Virginia Keywords: OFDM, Constant Envelope OFDM, Peak-to-Average Power Ratio, Software Defined Radio, GNU Radio Design and Implementation of a Constant Envelope OFDM Waveform in a Software Defined Radio Platform Amos Vershima Ajo Jr. ABSTRACT This thesis examines the high peak-to-average-power ratio (PAPR) problem of OFDM and other spectrally-efficient multicarrier modulation schemes, specifically their stringent requirements for highly linear, power-inefficient amplification. The thesis then presents a most intriguing answer to the PAPR-problem in the form of a constant-envelope OFDM (CE-OFDM) waveform, a waveform which employs phase modulation to transform the high-PAPR OFDM signal into a constant envelope signal, like FSK or GMSK, which can be amplified with non-linear power amplifiers at near saturation levels of efficiency. A brief analytical description of CE-OFDM and its suboptimal receiver architecture is provided in order to define and analyze the key parameters of the waveform and their performance impacts. The primary contribution of this thesis is a highly tunable software-defined radio (SDR) implementation of the waveform which enables rapid-prototyping and testing of CE-OFDM systems. The digital baseband processing of the waveform is executed on a general purpose processor (GPP) in the Ubuntu 14.04 Linux operating system, and programmed using the GNU Radio SDR software framework with a mixture of Python and C++ routines. -
N9064A & W9064A VXA Signal Analyzer Measurement Application Measurement Guide
Agilent X-Series Signal Analyzer This manual provides documentation for the following analyzers: PXA Signal Analyzer N9030A MXA Signal Analyzer N9020A EXA Signal Analyzer N9010A CXA Signal Analyzer N9000A N9064A & W9064A VXA Signal Analyzer Measurement Application Measurement Guide Agilent Technologies Notices © Agilent Technologies, Inc. Manual Part Number as defined in DFAR 252.227-7014 2008-2010 (June 1995), or as a “commercial N9064-90002 item” as defined in FAR 2.101(a) or No part of this manual may be as “Restricted computer software” reproduced in any form or by any Supersedes: July 2010 as defined in FAR 52.227-19 (June means (including electronic storage Print Date 1987) or any equivalent agency and retrieval or translation into a regulation or contract clause. Use, foreign language) without prior October 2010 duplication or disclosure of Software agreement and written consent from is subject to Agilent Technologies’ Agilent Technologies, Inc. as Printed in USA standard commercial license terms, governed by United States and Agilent Technologies Inc. and non-DOD Departments and international copyright laws. 1400 Fountaingrove Parkway Agencies of the U.S. Government Trademark Santa Rosa, CA 95403 will receive no greater than Acknowledgements Warranty Restricted Rights as defined in FAR 52.227-19(c)(1-2) (June 1987). U.S. Microsoft® is a U.S. registered The material contained in this Government users will receive no trademark of Microsoft Corporation. document is provided “as is,” and is greater than Limited Rights as subject to being changed, without defined in FAR 52.227-14 (June Windows® and MS Windows® are notice, in future editions. -
FM Stereo Format 1
A brief history • 1931 – Alan Blumlein, working for EMI in London patents the stereo recording technique, using a figure-eight miking arrangement. • 1933 – Armstrong demonstrates FM transmission to RCA • 1935 – Armstrong begins 50kW experimental FM station at Alpine, NJ • 1939 – GE inaugurates FM broadcasting in Schenectady, NY – TV demonstrations held at World’s Fair in New York and Golden Gate Interna- tional Exhibition in San Francisco – Roosevelt becomes first U.S. president to give a speech on television – DuMont company begins producing television sets for consumers • 1942 – Digital computer conceived • 1945 – FM broadcast band moved to 88-108MHz • 1947 – First taped US radio network program airs, featuring Bing Crosby – 3M introduces Scotch 100 audio tape – Transistor effect demonstrated at Bell Labs • 1950 – Stereo tape recorder, Magnecord 1250, introduced • 1953 – Wireless microphone demonstrated – AM transmitter remote control authorized by FCC – 405-line color system developed by CBS with ”crispening circuits” to improve apparent picture resolution 1 – FCC reverses its decision to approve the CBS color system, deciding instead to authorize use of the color-compatible system developed by NTSC – Color TV broadcasting begins • 1955 – Computer hard disk introduced • 1957 – Laser developed • 1959 – National Stereophonic Radio Committee formed to decide on an FM stereo system • 1960 – Stereo FM tests conducted over KDKA-FM Pittsburgh • 1961 – Great Rose Bowl Hoax University of Washington vs. Minnesota (17-7) – Chevrolet Impala ‘Super Sport’ Convertible with 409 cubic inch V8 built – FM stereo transmission system approved by FCC – First live televised presidential news conference (John Kennedy) • 1962 – Philips introduces audio cassette tape player – The Beatles release their first UK single Love Me Do/P.S. -
Angle Modulation
ANGLE MODULATION [email protected] Source : SIGA2800 Basic SIGINT Technology Objectives 1. Identify which modulations are also known as angle modulations. 2. Given a maximum modulating frequency and either a frequency of deviation or deviation ratio of a frequency modulated signal, determine signal bandwidth as given by Carson's rule. Objectives 3. Given a bandwidth and either a maximum frequency deviation or deviation ratio, calculate the maximum modulating frequency that will comply with Carson's rule. Objectives 4. Given a carrier being frequency modulated by a sine wave at a fixed deviation ratio, calculate: a. Average signal power b. Bandwidth in accordance with Carson's rule. c. Signal power present at the carrier frequency, any frequency harmonic, and at a frequency equal to the frequency deviation. Objectives 5. For angle modulated signals, identify what factors drive overall power in the signal. 6. State what factors affect the bandwidth of signals modulated using angle modulation. Sinewave Characteristics Phase Period Time 1 Frequency Period A sinusoid has three properties . These are its amplitude, period (or frequency), and phase. Types of Modulation Amplitude Modulation Phase Modulation Asin(t ) Asin(t ) Frequency Modulation With very few exceptions, phase modulation is used for digital information. Asin(t ) Types of Modulation Types of Information Carrier • Analog Variations Amplitude • Digital Frequency These two Phase constitute angle modulation. (Objective #1) WHAT IS ANGLE MODULATION? Angle modulation is a variation of one of these two parameters. UNDERSTANDING PHASE VS. FREQUENCY To understand the difference between phase and frequency, V a signal can be thought of phase using a phasor diagram. -
R&S®FSW-K70 Measuring the BER and the EVM for Signals With
R&S®FSW-K70 Measuring the BER and the EVM for Signals with Low SNR Application Sheet Signals with low signal-to-noise ratios (SNR) often cause bit errors during demodulation, so that modula- tion accuracy values such as the error vector magnitude (EVM) may not be determined correctly. This application sheet describes: ● The significance of the Bit Error Rate (BER) parameter for signal analysis ● How the R&S FSW VSA application calculates the BER and determines bit errors ● How this knowledge can be used to obtain correct modulation accuracy results (;ÜOÔ2) 1178.3170.02 ─ 01 Application Sheet Test & Measurement R&S®FSW-K70 Contents Contents 1 Introduction............................................................................................ 2 2 How to Create Known Data Files..........................................................3 3 BER Measurement in the R&S FSW VSA application.........................6 4 Tips for Improving Signal Demodulation in Preparation for the Known Data File..................................................................................... 8 5 Measurement Example - Measuring the BER....................................14 6 Additional Information.........................................................................16 1 Introduction What is the Bit Error Rate (BER)? In signal analysis, a bit error occurs when a false symbol decision is made during demodulation. That is: the demodulated symbol does not correspond to the transmitted symbol. Bit errors often occur when demodulating highly distorted signals -
Generation of Carrier Signal Using Different Oscillators for ISM and Wi-Fi Band Applications
IOSR Journal of Electronics and Communication Engineering (IOSR-JECE) e-ISSN: 2278-2834, p-ISSN: 2278-8735 PP 25-29 www.iosrjournals.org Generation of carrier signal using different oscillators for ISM and Wi-Fi band applications Pangavhane S.M.1, Patil P.A.2&Gite A.H.3 1,2,3(E&TC Engg. Dept.,S.I.E.RAgaskhind, SPP Univ., Pune(MS), India) Abstract : Oscillator is one of the Basic blocks in communication system. Oscillators generate the carrier signals which are to be modulated with the original message signal for transmission. The oscillators are designed mainly for ISM & Wi-Fi band applications using different technologies viz. 45nm, 65nm, 90nm.This paper deals with the most efficient design process of different types of oscillators using microwind 3.5. The different types of oscillators viz. Ring oscillator, voltage controlled oscillator are designed with minimum power consumption and minimum area on chip. Keywords –Microwind 3.5, Ring Oscillator, VCO, Frequency, Power Consumption. 1. INTRODUCTION Nowadays communication plays a vital role in human life and had become an integrated part of it. Communication includes transmission of signal from source to destination. We cannot transmit the message signal directly from the source to destination, as there is a need to modulate the signal before transmission. So we need a carrier signal of relatively high frequency to carry out the modulation process conveniently. This carrier signal will be generated by a device known as an oscillator. The communication process mainly consists of two phases, i.e. modulation at transmitter end and demodulation at receiver end. -
Fact Sheet No.11 Radio Frequency (RF) Emissions Classification
Fact Sheet No.11 Radio Frequency (RF) Emissions Classification The Minister responsible for Telecommunications, through the Telecommunications Unit, is charged with the responsibility of ensuring that the Radio Frequency (RF) emissions, classification adopted by Barbados conforms to well defined conventions, in accordance with the International Telecommunication Union (ITU) Radio Regulations. RF emissions are the result of radiated electromagnetic energy. They are produced by radio transmitting stations and can be utilized by radio equipment. RF emissions occur at frequencies ranging from 3kHz to 3000GHz within the radio spectrum. These emissions show differences in characteristics that are mainly dependent on their frequencies. This fact has led to the grouping together of these emissions into nine frequency bands. Different techniques are then used to propagate these various bands. Inherent characteristics dictate how these emissions can be utilized for the purpose of communication. Electrical current or voltage can be varied over time in order to produce signals which carry information. Emissions can be used to carry information by processing them in such a way as to carry signals. The process, called modulation involves the modification of the carrier by another signal or wave (the modulating wave). The resultant composite signal is the modulated wave. The process of modulation is accomplished in several ways, amongst these are - • Amplitude modulation (AM) - a type of modulation in which the amplitude of the carrier wave is varied above and below its unmodulated value by an amount proportional to the amplitude of the signal wave and at the frequency of the modulating signal. • Frequency modulation (FM) - a type of modulation in which the frequency is varied above and below its unmodulated value by an amount proportional to the amplitude of the signal wave and at a frequency of the modulating signal.