DOCSLIB.ORG

11 Electromagnetic Waves 3 Radio Communication MAINIDEA Write the Main Idea for This Lesson

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
11 Electromagnetic Waves 3 Radio Communication MAINIDEA Write the Main Idea for This Lesson 11 Electromagnetic Waves 3 Radio Communication MAINIDEA Write the Main Idea for this lesson. Radio waves and microwaves can be used to transmit signals and information. REVIEW VOCABULARY Recall the definition of the Review Vocabulary term. amplitude amplitude a measure of the size of the disturbance a wave produces NEW VOCABULARY Use your book to define the following key terms. carrier wave carrier wave the specific frequency of the electromagnetic wave that modulation a radio station is assigned analog signal modulation the process of adding the signal wave to the carrier wave digital signal transceiver Global Positioning System analog signal electric signals whose amplitudes change smoothly (GPS) over time digital signal electric signals that have only two values—ON and OFF transceiver a device that transmits one radio signal and receives another Global Positioning System (GPS) a system of satellites, monitoring Copyright © McGraw-Hill Education © McGraw-Hill Copyright stations, and receivers to determine an object’s location near Earth’s surface ACADEMIC VOCABULARY Use a dictionary to define transmit. transmit transmit to send from one location to another Science Notebook • Electromagnetic Waves 177 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 177177 007/05/137/05/13 11:44:44 AAMM Program: TX HS Science Component: IPC SCI NTBK PDF PASS Vendor: LASERWORDS Grade: N/A 3 Radio Communication (continued) Student Edition, pp. 352–354 Compare AM and FM radio transmission by completing the organizer Reading Essentials, below. pp. 204–206 Radio Transmission AM radio stations FM radio stations broadcast information by broadcast information by changing the amplitude of changing the frequency the carrier wave. of the carrier wave. GET IT? Compare and contrast AM and FM radio signals. AM radio modulates the amplitude of the carrier wave; FM radio modulates the frequency of the carrier wave. AM waves have lower frequencies than FM waves. GET IT? Describe how a radio signal’s strength changes as you move away from the tower. The radio signal gets weaker as you move away from the tower. Complete the flowchart below to describe the transmission of television signals. Before 2009 TV signals were analog signals, which changed smoothly. Education © McGraw-Hill Copyright Information about color and Information abut sound brightness was sent by was sent on FM waves. AM waves. Beginning in 2009 all TV signals are digital signals. Digital signals are either ON or OFF , like a light switch. Because the switch to digital signals, very complex digital modulation can be carried on a single wave . Science Notebook • Electromagnetic Waves 178 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 178178 007/05/137/05/13 11:44:44 AAMM Program: TX HS Science Component: IPC SCI NTBK PDF PASS Vendor: LASERWORDS Grade: N/A 3 Radio Communication (continued) Student Edition, pp. 355–357 Organize what you have learned about telephones by completing the Reading Essentials, table below. pp. 206–208 Type Features Advantage Disadvantage Corded stays in one sends/receives must use in place consistent signal one place Cordless base stays in not linked to the must use near one place base base, can be overheard Pager portable newer ones only responds can send/ to messages receive data with its own ID number Cellular portable not linked to tower needed base Create a sketch to show how a satellite telephone system works. • Use arrows to show the path of the signal. • Include the sender, a satellite, and the receiver in your sketch Sketches should include the sender, with arrows showing the signal moving toward the satellite. Arrows should show the signal moving down toward the receiver. Copyright © McGraw-Hill Education © McGraw-Hill Copyright ANALYZE IT Analyze the information on the Global Positioning System. Infer why the system uses data from four different satellites when locating an object. Accept all reasonable responses. Information from four satellites can locate an exact place. Two receivers give two possible locations. Science Notebook • Electromagnetic Waves 179 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 179179 007/05/137/05/13 11:44:44 AAMM Program: TX HS Science Component: IPC SCI NTBK PDF PASS Vendor: LASERWORDS Grade: N/A 3 Radio Communication (continued) REVIEW IT ! 14. MAINIDEA Identify and describe the steps that a radio station uses to broadcast sounds to your radio receiver. Sounds at the radio station are converted into an electrical signal. This signal causes electrons in the broadcast antenna to vibrate. The vibrating electrons produce electromagnetic waves, which travel outward. The electromagnetic wave encounters a radio receiver antenna. The electric and magnetic fields of the wave cause the electrons in the receiver antenna to vibrate. The vibrating electrons provide the electrical signal that the radio converts back into sound. 15. Explain the difference between AM and FM radio. Make a sketch of how a carrier wave is modulated in AM and FM radio signals. Students’ sketches should resemble For AM, amplitude is modulated. For FM, frequency Figure 19. is modulated. 16. Describe what happens to your signal when you are talking on a cell phone and you travel from one cell to another cell. Copyright © McGraw-Hill Education Education © McGraw-Hill Copyright A central controller transfers your signal to the base station in the new cell. 17. Explain some of the uses of the Global Positioning System. Why might emergency vehicles be equipped with GPS receivers? GPS is used by hikers, airplanes, ships, cars, and others to identify their locations on Earth. Emergency vehicles have GPS receivers to help them find places quickly. Science Notebook • Electromagnetic Waves 180 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 180180 114/05/134/05/13 112:142:14 AAMM Program: TX HS Science Component: IPC SCI NTBK PDF PASS Vendor: LASERWORDS Grade: N/A 3 Radio Communication (continued) 18. Think Critically Why do cordless telephones stop working when you move too far from the base unit? The strength of the signal decreases with distance, and the signal becomes too weak to be detected by the handset. 19. Calculate a Ratio A TV screen is composed of many points of light called pixels. A standard TV has 460 pixels horizontally and 360 pixels vertically. A high-definition TV has 1,920 horizontal and 1,080 vertical pixels. What is the ratio of the number of pixels in a high-definition TV to the number in a standard TV? (1,920 × 1,080) to (460 × 360) = 2,073,600 to 165,600 = 25 to 2 Copyright © McGraw-Hill Education © McGraw-Hill Copyright Science Notebook • Electromagnetic Waves 181 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 181181 007/05/137/05/13 11:44:44 AAMM Program: TX HS Science Component: IPC SCI NTBK PDF PASS Vendor: LASERWORDS Grade: N/A 1167_182_IPC_SN_C11_143655.indd67_182_IPC_SN_C11_143655.indd 182182 007/05/137/05/13 11:44:44 AAMM.
Load more

Recommended publications
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • 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.
    [Show full text]
  • A Short History of Radio
    Winter 2003-2004 AA ShortShort HistoryHistory ofof RadioRadio With an Inside Focus on Mobile Radio PIONEERS OF RADIO If success has many fathers, then radio • Edwin Armstrong—this WWI Army officer, Columbia is one of the world’s greatest University engineering professor, and creator of FM radio successes. Perhaps one simple way to sort out this invented the regenerative circuit, the first amplifying re- multiple parentage is to place those who have been ceiver and reliable continuous-wave transmitter; and the given credit for “fathering” superheterodyne circuit, a means of receiving, converting radio into groups. and amplifying weak, high-frequency electromagnetic waves. His inventions are considered by many to provide the foundation for cellular The Scientists: phones. • Henirich Hertz—this Clockwise from German physicist, who died of blood poisoning at bottom-Ernst age 37, was the first to Alexanderson prove that you could (1878-1975), transmit and receive Reginald Fessin- electric waves wirelessly. den (1866-1932), Although Hertz originally Heinrich Hertz thought his work had no (1857-1894), practical use, today it is Edwin Armstrong recognized as the fundamental (1890-1954), Lee building block of radio and every DeForest (1873- frequency measurement is named 1961), and Nikola after him (the Hertz). Tesla (1856-1943). • Nikola Tesla—was a Serbian- Center color American inventor who discovered photo is Gug- the basis for most alternating-current lielmo Marconi machinery. In 1884, a year after (1874-1937). coming to the United States he sold The Businessmen: the patent rights for his system of alternating- current dynamos, transformers, and motors to George • Guglielmo Marconi—this Italian crea- Westinghouse.
    [Show full text]
  • Performance of Coherent Direct Sequence Spread Spectrum
    PERFORMANCE OF COHERENT DIRECT SEQUENCE SPREAD SPECTRUM FREQUENCY SHIFT KEYING A thesis presented to the faculty of the Russ College of Engineering and Technology of Ohio University In partial fulfillment of the requirements for the degree Master of Science Sudhir Kumar Sunkara November 2005 This thesis entitled PERFORMANCE OF COHERENT DIRECT SEQUENCE SPREAD SPECTRUM FREQUENCY SHIFT KEYING by SUDHIR KUMAR SUNKARA has been approved for the School of Electrical Engineering and Computer Science and the Russ College of Engineering and Technology by David W. Matolak Associate Professor of Electrical Engineering and Computer Science Dennis Irwin Dean, Russ College of Engineering and Technology SUNKARA, SUDHIR KUMAR. M.S. November 2005. Electrical Engineering and Computer Science Performance of Coherent Direct Sequence Spread Spectrum Frequency Shift Keying (83pp.) Director of Thesis: David W. Matolak We analyze the performance of a multi-user coherently-detected direct sequence spread spectrum frequency shift keying modulated system. Detection is done with respect to an arbitrary user. We derive bit error probability expressions for both synchronous and asynchronous systems. For the synchronous system, we analyze different variations of the system in order to ensure orthogonality. Orthogonality is achieved via both frequency separation and orthogonal codes. In the asynchronous system, orthogonality is achieved only through frequency separation. The channel impairments considered were additive white Gaussian noise and multi-user interference. We then extend this to a Rayleigh fading channel, and provide analytical and simulation results for single user and multi- user cases. We also analyzed the spectral characteristics of these systems. Approved: David W. Matolak Associate Professor of Electrical Engineering and Computer Science Acknowledgements I would like to thank my thesis advisor Dr.
    [Show full text]
  • Communication Systems Amplitude Modulation (AM)
    16.002 Lecture (8) Communication Systems Amplitude Modulation (AM) April 9, 2008 Today’s Topics 1. Amplitude modulation of signals 2. Application issues Take Away Fourier Transform methods facilitate the understanding of modulation in communication systems Required Reading O&W-8.0, 8.1, 8.2, 8.3, 8.7 Communication systems typically transmit information that has content at relatively low frequencies by encoding it, in one fashion or another, onto carrier signals at much higher frequencies. For example, amplitude modulated (AM) commercial radio broadcasting systems typically transmit voice and music signals using electromagnetic waves that pass readily through the atmosphere. The voice and music signals have frequency content typically in the range of about 20 Hz (cycles per second) up to about 20 kHz (thousands of cycles per second). The physical characteristics of the atmosphere make it very difficult for signals at these frequencies to be transmitted at distances beyond a few meters. Rather, these signals are encoded onto high frequency sinusoidal carrier signals that are in the range of 520 kHz up to 1.75 MHz (millions of cycles per second), by modulating the amplitude of the carrier wave. Typically the frequency of the carrier is one or more orders of magnitude greater than the frequency of the signal it is “carrying”. Fourier transform methods are an ideal means for understanding the workings of these kinds of communication systems. Amplitude Modulation We will start our study of communications systems by first analyzing the AM method of communicating signals. The two most common forms of amplitude modulation use either a complex carrier or a single sinusoidal carrier.
    [Show full text]
  • Design and Construction of Fm Transmiter with the Range of 1.5 Km
    ISSN 2349-7815 International Journal of Recent Research in Electrical and Electronics Engineering (IJRREEE) Vol. 5, Issue 3, pp: (1-5), Month: July - September 2018, Available at: www.paperpublications.org DESIGN AND CONSTRUCTION OF FM TRANSMITER WITH THE RANGE OF 1.5 KM 1M. I. Efunbote, 2T. I. Ibrahim, 3J. O. Otulana, 4R. A. Jokojeje 1Department of Electrical /Electronics Engineering, Moshood Abiola Polytechnic, Abeokuta, Ogun State, Nigeria 2Department of Mechanical Engineering, Moshood Abiola Polytechnic, Abeokuta, Ogun State, Nigeria Abstract: This research work highlighted major components of an FM transmitter consisting of audio unit, modulating unit, amplifier unit, RF(Radio Frequency) amplifier unit and transmitting unit. These units worked together to achieve the desired results. The transmitter itself generated alternating current, which was applied to the antenna when excited by this alternating current, basically a VHF colpitt oscillator capable of transmitting sound to any standard FM receiver. The circuit worked on a DC source which was got from rectification. This was made use of by the FM (Frequency Modulation ) transmitter and a capacitor microphone which picked up a very weak signal. The electrical signal was then applied to FM (Frequency Module) transmitter where the signal was then frequency modulated with a carrier frequency. The modulated signal was then transmitted to the medium through a transmitting antenna. FM transmitter could be used as cordless microphone, mobile phones and public address purpose. The antenna was attached to the transmitter in a portable device such as cell phone and walkie talkie, the antenna might be located on top of a building or a separate tower and connected to the transmitter by a feed line, that is transmitting line.
    [Show full text]
  • Lesson 3: Introduction to Modulation Methods
    Mobile Communication – An overview Lesson 03 Introduction to Modulation Methods © Oxford University Press 2018. All rights reserved. 1 Modulation • The process of varying signal, called carrier, according to the pattern provided by another signal (modulating signal) • The carrier usually an analog signal selected to match the characteristics of a particular transmission system. … © Oxford University Press 2018. All rights reserved. 2 …Modulation • The amplitude, frequency, or phase angle of a carrier wave is varied in proportion to the variation in amplitude of the modulating wave (message signal) © Oxford University Press 2018. All rights reserved. 3 Equation for signal amplitude at an instant t, s(t) s(t) = s0 sin [(2 c/ t) + t0 ] = s0 sin [(2 f t) + t0] • s0 ─ the peak amplitude (amplitude varies between s0 and –s0) • c ─ the velocity of the transmitted wave • t0─ the phase angle of the signal at t = 0 (a reference point with respect to which t is considered) • f─ the signal frequency © Oxford University Press 2018. All rights reserved. 4 Modulation of the voice or data signal A technique by which fc or a set of carrier frequencies used for wireless transmission such that • peak amplitude, sc0, or • frequency, fc, or • Phase angle ct0 varies with t in proportion to the peak amplitude of the modulating signal sm(t) © Oxford University Press 2018. All rights reserved. 5 Modulation • Amplitude modulation (AM) if amplitude sc0 of carrier varied • Frequency modulation (FM) if frequency fc varied • Phase modulation if phase angle t0 varied © Oxford University Press 2018. All rights reserved. 6 Amplitude Modulation (AM) © Oxford University Press 2018.
    [Show full text]
  • Quadrature Amplitude Modulation )
    1 Elements of a Transmission System • Input signal coming from transducer (source) • Transmitted signal suitable to the characteristics of the transmission channel (involves encoding and modulation) • Channel introduces some amount of attenuation and signal distorsion • In the channel noise is also generated which produce alterations of the signal shape • Receiver include filtering to take away out-of-band noise, amplification to compensate for channel attenuation, equalizing to compensate for distortion, demodulation and decoding Basic concept of transmission system. 118 2 Modulation Methods • Modulation: generate a signal suited to the characteristics of a transmission channel • The message, s(t), alters the amplitude, phase or frequency of the high-frequency carrier: – Amplitude: AM (amplitude modulation), A = A [s(t)] – Frequency: FM (frequency modulation), f = f [s(t)] – Phase: PM (phase modulation), φ = φ [s(t)] s(t) A cos (2 π f0 t + φ) 119 3 Amplitude modulation The original carrier wave has a constant peak value (amplitude) and it has a much higher frequency than the modulating signal, the message 120 4 Frequency modulation 121 5 Phase modulation In PM the instantaneous phase is varied linearly according to the message 122 Digital PM 6 In digital binary PM, called binary phase shift keying (BPSK), the phase of the carrier is varied according to whether the digital signal is “1” or “0”. We need only two carrier phases, which are chosen to be 0° for binary 0 and 180° for binary 1: When four carrier phases are used, each phase transmits the value of two binary bits and we talk about quadrature phase shift keying (QPSK).
    [Show full text]
  • Radio; *Federal Laws; *Mass Media; Radio; Radio Technology; Television IDENTIFIERS FCC; Federal Communications Commission
    DOCUMENT RESUME ED 064 941 EM 010 062 TITLE Broadcast Services; Evolution of Broadcasting. INSTITUTION Federal Communications Commission, Washington, D.C. REPORT NO 2-B-1-72 PUB DATE 72 NOTE 52p.; Information Bulletin EDRS PRICE MF-$0065 BC-43.29 DESCRIPTORS *Broadcast Industry; *Communications; Educational Radio; *Federal Laws; *Mass Media; Radio; Radio Technology; Television IDENTIFIERS FCC; Federal Communications Commission ABSTRACT The structure, history, technology and especially regulation of broadcasting in general are summarized in thisFederal COMMunication Commission (FCC) information bulletin. Further Specifics of history, technology, structure andregulation are presented for AM radio, FM radio, television,educational broadcasting, and broadcast relay by satellite. MO U,S, DEPARTMENT OFHEALTH, EDUCATION & WELFARE OFFICE OF EDUCATION Broadcast THIS DOCUMENT HASSEEN REPRO. DUCED EXACTLY AS RECEIVEDFROM THE PERSON OR ORGANIZATIONORIG- INATING IT. POINTS OF VIEW Services OR OPIN- IONS STATED DO NOTNECESSARILY REPRESENT OFFICIAL OFFICEOF EDU- CATION POSITION OR POLICY 2-B 1/72 One of the most dramatic EVOLUTION developments of 20th Century OF technology hasbeen theuse of BROADCASTING radio waves--electromagnetic radiations traveling at the speed of light--for communication. Radio communication designed for reception by the general public is known as "broadcasting." Radio waves of different frequencies (number of cycles per second) can be "tuned." Hence, signals from many sources can be received on a radio set without interfering with each other. In everyday language the term. "radio" refers tO aural (sound) broad- casting, which is received from ampli- tude-modulated (AM) or frequency-modu- lated (FM) stations. "Television," another form of radio, is received from stations making both visual and aural transmissions.
    [Show full text]
  • Communication Signals and Radio Receiver
    Communication Signals and Radio Receiver Project Description: In this lesson we will examine the background and history of communication systems and signals. We will utilize internet websites and computer programs to understand the type of signals. Finally, we will build our own Radio Receiver circuit to listen to an AM station. Project Objectives The Students in the lesson will learn the basics of communication signal, and its types. The Students in the lesson will understand and characterize the type of frequencies, low, mid, and high. The Students in the lesson will finally will build a radio receiver circuit. The Students in the lesson will understand basics of soldering and how to do soldering. Materials Needed AM Radio Kit, Computer with internet access, Pencils, Soldering Iron Stations, Solder, De soldering wax, and Wires. North Dakota State Standards: 9-10.1.1. Explain how models can be used to illustrate scientific principles 9-10.2.2. Use appropriate safety equipment and precautions during investigations. 9-10.6, 1. Use appropriate technologies and technique to solve a problem. 9-10.8.3. Explain how individuals and groups, from different disciplines in and outside of science, contribute to science at different levels of complexity. Session Organization 11:00-11:30 Cultural connection 11:30-12:00 Background information using power point 12:00-12:30 Lunch 12:30-1:00 Computer Activity on signals, and its types 1:00-2:30 Work on soldering AM receiver 2:30-3:00 Demo and student presentation Application and Career paths: Signal Engineer, Radio Engineer, Communication Engineers, Scientists, and Wireless Engineer.
    [Show full text]
  • Signal Processing for Parametric Acoustic Sources Applied to Underwater Communication †
    sensors Article Signal Processing for Parametric Acoustic Sources Applied to Underwater Communication † María Campo-Valera 1 , Ivan Felis-Enguix 2,* and Isidro Villó-Pérez 1 1 Departamento de Electrónica, Tecnología de Computadores y Proyectos, Universidad Politécnica de Cartagena (UPCT), 30202 Cartagena, Murcia, Spain; [email protected] (M.C.-V.); [email protected] (I.V.-P.) 2 Laboratorio de Hidroacústica (LHA), Centro Tecnológico Naval y del Mar (CTN), Ctra El Estrecho-Lobosillo, Km. 2, 30320 Fuente Álamo, Murcia, Spain * Correspondence: [email protected] † This paper is an extended version of the conference paper: Campo-Valera, M.; Felis, I. Underwater Acoustic Communication for The Marine Environment’s Monitoring. In Proceedings of the The 6th International Electronic Conference on Sensors and Applications (ECSA-6), online, 15–30 November 2019. Received: 31 July 2020; Accepted: 12 October 2020; Published: 17 October 2020 Abstract: For years, in the field of underwater acoustics, a line of research with special relevance for applications of environmental monitoring and maritime security has been developed that explores the possibilities of non-linear phenomena of sound propagation, especially referring to the so-called parametric effect or self-modulation. This article shows the results of using a new modulation technique based on sine-sweep signals, compared to classical modulations (FSK and PSK). For each of these modulations, a series of 16-bit strings of information with different frequencies and durations have been performed, with the same 200 kHz carrier wave. All of them have been tested in the Hydroacoustic Laboratory of the CTN and, through the application of cross-correlation processing, the limitations and improvements of this novel processing technique have been evaluated.
    [Show full text]