This topic will provide a detailed study about the optical heterodyne detection and its working. A heterodyne is a signal frequency that is created by combining or mixing two other frequencies using a signal processing technique called heterodyning.
Heterodyning is used to shift one frequency range into another, new frequency range, and is also involved in the processes of modulation and demodulation.
The two input frequencies are combined in a nonlinear signal-processing device such as a vacuum tube, transistor, or diode, usually called a mixer.
The attached narrated power point presentation offers a block level and an elementary level mathematical treatment of optical communication systems employing coherent detection. The material will immensely benefit KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation offers a block level and an elementary level mathematical treatment of optical communication systems employing coherent detection. The material will immensely benefit KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
Measurement of optical fiber refractive indexCKSunith1
The attached narrated power point presentation discusses the various methods for measurement of refractive index of an optical fiber. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
Optical Fiber Communication Part 3 Optical Digital ReceiverMadhumita Tamhane
Current generated by photodetector is very weak and is adversely effected by random noises associated with photo detection process. When amplified, this signal further gets corrupted by amplifiers. Noise considerations are thus important in designing optical receivers.
Most meaningful criteria for measuring performance of a digital communication system is average error probability, and in analog system, it is peak signal to rms noise ratio. ...
Detection techniques in coherent optical communicationsCKSunith1
The attached narrated power point presentation attempts to explain the block diagrams of different detection schemes used in coherent optical communication receivers. The material also makes an attempt to compare the various detection schemes used as well, and will be useful to KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the different types of tunable filters for WDM Systems. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
This narrated power point presentation attempts to explain the various dispersion mechanisms that are observed in optical fibers. Some fundamental terms and concepts are also discussed. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the methods of computation of total power loss and system rise time in a fiber optic link. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the working principle, types, classifications, merits, demerits, applications,safety and deployment issues related to Raman Amplifiers. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
A Klystron is a vacuum tube that can be used either as a generator or as an amplifier or as an oscillator, at microwave frequencies.The Klystron is a linear beam device; that is, the electron flow is in a straight line focused by an axial magnetic field.
Development of a receiver circuit for medium frequency shift keying signals.inventionjournals
Frequency shift keying (fsk) mode of digital signal information transfer switches between two predetermined frequencies of the carrier wave, either by modulating one sine wave oscillator or by switching between two oscillators.The need for a receiver to decode an fsk signal along the transmitting medium from a digital source code within about 5 kilometer radius for security monitoring of environment informed this work. The design of a receiver circuit at a frequency of 500 kHzfor an input frequency shift keying (fsk) signal from a transmitter is presented. The receiver is to receive an RF signal, amplify it, filter it to remove unwanted signals, and recover the desired base band information. It consists of an amplifier, tuned circuitsand mixers which filters the base-band information. A comparator circuit is incorporated, to detect the digital signal received. The output from the comparators is the digital equivalent of the coded signals sent by the transmitter circuit, and transferred to a microcontroller circuit, to act as a coded signal representing information from the transmitting end. The bode-plot response of the receiver to the incoming signals using a FET tuned circuit, shows that only frequencies above 470kHz, and below 495kHz are allowed to pass through the network with a resonant frequency of 483.553 kHz and a gain of 27.734dB, while others are totally attenuated. The reliability of the designed receiver circuit was evaluated for a 1 year continuous operating period and was found to be 74.7%.Area of application of this work include electronic policing of a defined environment with good success
Measurement of optical fiber refractive indexCKSunith1
The attached narrated power point presentation discusses the various methods for measurement of refractive index of an optical fiber. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
Optical Fiber Communication Part 3 Optical Digital ReceiverMadhumita Tamhane
Current generated by photodetector is very weak and is adversely effected by random noises associated with photo detection process. When amplified, this signal further gets corrupted by amplifiers. Noise considerations are thus important in designing optical receivers.
Most meaningful criteria for measuring performance of a digital communication system is average error probability, and in analog system, it is peak signal to rms noise ratio. ...
Detection techniques in coherent optical communicationsCKSunith1
The attached narrated power point presentation attempts to explain the block diagrams of different detection schemes used in coherent optical communication receivers. The material also makes an attempt to compare the various detection schemes used as well, and will be useful to KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the different types of tunable filters for WDM Systems. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
This narrated power point presentation attempts to explain the various dispersion mechanisms that are observed in optical fibers. Some fundamental terms and concepts are also discussed. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the methods of computation of total power loss and system rise time in a fiber optic link. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
The attached narrated power point presentation attempts to explain the working principle, types, classifications, merits, demerits, applications,safety and deployment issues related to Raman Amplifiers. The material will be useful for KTU final year B Tech students who prepare for the subject EC 405, Optical Communications.
A Klystron is a vacuum tube that can be used either as a generator or as an amplifier or as an oscillator, at microwave frequencies.The Klystron is a linear beam device; that is, the electron flow is in a straight line focused by an axial magnetic field.
Development of a receiver circuit for medium frequency shift keying signals.inventionjournals
Frequency shift keying (fsk) mode of digital signal information transfer switches between two predetermined frequencies of the carrier wave, either by modulating one sine wave oscillator or by switching between two oscillators.The need for a receiver to decode an fsk signal along the transmitting medium from a digital source code within about 5 kilometer radius for security monitoring of environment informed this work. The design of a receiver circuit at a frequency of 500 kHzfor an input frequency shift keying (fsk) signal from a transmitter is presented. The receiver is to receive an RF signal, amplify it, filter it to remove unwanted signals, and recover the desired base band information. It consists of an amplifier, tuned circuitsand mixers which filters the base-band information. A comparator circuit is incorporated, to detect the digital signal received. The output from the comparators is the digital equivalent of the coded signals sent by the transmitter circuit, and transferred to a microcontroller circuit, to act as a coded signal representing information from the transmitting end. The bode-plot response of the receiver to the incoming signals using a FET tuned circuit, shows that only frequencies above 470kHz, and below 495kHz are allowed to pass through the network with a resonant frequency of 483.553 kHz and a gain of 27.734dB, while others are totally attenuated. The reliability of the designed receiver circuit was evaluated for a 1 year continuous operating period and was found to be 74.7%.Area of application of this work include electronic policing of a defined environment with good success
RF testing has remained hype for most of us. But seriously it is not so. It can be very interesting and one can develop a lot of interest in this if given an opportunity.
In this paper, authors have started with the some basic concepts of radio engineering which we studied in engineering and built upon these concepts to use in practical applications.
We have also described the basic principles of Signal Analyzer and Signal Generator which are the most common test tools used for any radio testing.
Luigi Giubbolini | Time/Space-Probing Interferometer for Plasma DiagnosticsLuigi Giubbolini
By Luigi Giubbolini Published article about Rapid progress in plasma applications requires new instrumentation. Luigi Giubbolini has engineering experience in industrial, government laboratory & academic environments.
A New Underwater Acoustic Navigation Method Based on the Doppler PrincipleNooria Sukmaningtyas
In this paper, a new underwater acoustic navigation method is proposed, which is named from
Doppler Acoustic Omnirange Beacon (DAOB). It is borrowed from the idea of Doppler VHF Omnirange
(DVOR) and based on the Doppler principle. The cause of Doppler effect in the received signal is the
motion or position change of one or two sources. The effect of multipath is analyzed, and an improved
signal form is presented to solve the rigorous multipath environment underwater. Some simulation is
presented to verify the performance.
In this paper, an adaptive control system is employed in a novel implementation technique of feedforward linearization system for optical analog communication systems’ laser transmitter. The adaptive control system applies the Newton trust-region dogleg algorithm, which is a numerical optimization algorithm, to automatically tune the adjustment parameters in the feedforward loops to optimize the feedforward system performance and adapt to process variations. At the end of the paper, significant reductions of over 20 dBm in the third-order intermodulation distortion products have been achieved for operating frequencies from 5.0 to 5.8 GHz.
Simulation of speech recognition using correlation method on matlab softwareVaishaliVaishali14
The following content gives a brief detail about the topic
INTRODUCTION
VOICE RECOGNITION
TYPES OF VOICE RECOGNITION SYSTEMS
CORRELATION
PROGRAM
PROGRAM EXPLANATION
OUTPUTS
INFERENCE
REFERENCE
SIMULATION OF AN ELECTRONIC DICE CIRCUIT USING LEDs IN PROTEUS SOFTWARE VaishaliVaishali14
The following content consists of the brief details about the topic
INTRODUCTION
CONCEPT OF ASTABLE MULTI VIBRATOR
CONCEPT OF DECADE COUNTER IC4017
CIRCUIT EXPLANATION
CIRCUIT DIAGRAM
VIDEO OF CIRCUIT WORKING
WORKING OF CIRCUIT
INFERENCE
REFERENCE
PERFORMANCE ANALYSIS OF 2*2 MIMO CHANNEL USING ZF EQUALIZER VaishaliVaishali14
The following content are present related to performance analysis of 2*2 mimo channel equalization technique
OBJECTIVE
INTRODUCTION
MIMO
2X2 MIMO CHANNEL
2X2 MIMO CHANNEL WITH ZF EQUALIZER
BER OF 2x2 MIMO CHANNEL WITH ZF EQUALIZER
PROGRAM AND SIMULATION OUTPUTS
RESULTS AND DISCUSSION
CONCLUSION
REFERENCES
Signals travels from the transmitter (object) to the receiver (your eye) along this straight line. This type of travel is called line of sight propagation.
Radio waves with frequencies greater than about 2MHz have line of sight propagation characteristic.
If the earth were flat, everything would be fine with this type of propagation.
This file consists of the following things related to line of sight propagation
INTRODUCTION
LINE OF SIGHT PROPAGATION
NON LINE OF SIGHT PROPAGATION
DISTANCE B/W TWO ANTENNA
RELATIONSHIP B/W HEIGHT OF ANTENNA AND RADIUS OF EARTH
LOS WIRELESS TRANSMISSION IMPAIRMENTS
APPLICATION OF LINE OF SIGHT PROPAGATION
LIMITATION OF LINE OF SIGHT PROPAGATION
REFERENCES
This topic will cover the listed topics below regarding linear equalization and its variations:
Fundamental of equalization
Equalizer
Categories of equalization
Depending on the time nature
Structure of adaptive equalization
Classification of equalizer
Linear equalizer
Transversal equalizer
Lattice equalizer
Advantage and disadvantages of lattice
Disadvantages of linear equalizer
Equalization, diversity, and channel coding are three techniques which can be used independently or in tandem to improve received signal quality.
Equalization compensates for intersymbol interference (ISI) created by multipath within time dispersive channels.
If the modulation bandwidth exceeds the coherence bandwidth of the radio channel, ISI occurs and modulation pulses are spread in time.
An equalizer within a receiver compensates for the average range of expected channel amplitude and delay characteristics.
Equalizers must be adaptive since the channel is generally unknown and time varying.
The main aim of the assignment is to simulate handoff performance using MATLAB code.
In this assignment we have done the performance of handoff using matlab code.
Soft Handoffs are generally used in MS that employ Code Division Multiple Access (CDMA) or Wideband CDMA (WCDMA), and its associated services, and also in applications that require a continuous connection throughout, possibly for security purposes.
Hard Handoffs are implemented in TDMA devices, used in applications that can afford slight delays, such as Internet, and WiMAX.
This project will provides a detailed explanation about a smart traffic light controller using verilog code along with test bench and the working principle and simulation outputs are been attached.
This presentation has given a brief introduction and working of CMOS Logic Structures which includes MOS logic, CMOS logic, CMOS logic structure, CMOS complementary logic, pass transistor logic, bi CMOS logic, pseudo –nMOS logic, CMOS domino logic, Cascode Voltage Switch Logic(CVSL), clocked CMOS logic(c²mos), dynamic CMOS logic
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
CFD Simulation of By-pass Flow in a HRSG module by R&R Consult.pptxR&R Consult
CFD analysis is incredibly effective at solving mysteries and improving the performance of complex systems!
Here's a great example: At a large natural gas-fired power plant, where they use waste heat to generate steam and energy, they were puzzled that their boiler wasn't producing as much steam as expected.
R&R and Tetra Engineering Group Inc. were asked to solve the issue with reduced steam production.
An inspection had shown that a significant amount of hot flue gas was bypassing the boiler tubes, where the heat was supposed to be transferred.
R&R Consult conducted a CFD analysis, which revealed that 6.3% of the flue gas was bypassing the boiler tubes without transferring heat. The analysis also showed that the flue gas was instead being directed along the sides of the boiler and between the modules that were supposed to capture the heat. This was the cause of the reduced performance.
Based on our results, Tetra Engineering installed covering plates to reduce the bypass flow. This improved the boiler's performance and increased electricity production.
It is always satisfying when we can help solve complex challenges like this. Do your systems also need a check-up or optimization? Give us a call!
Work done in cooperation with James Malloy and David Moelling from Tetra Engineering.
More examples of our work https://www.r-r-consult.dk/en/cases-en/
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
TECHNICAL TRAINING MANUAL GENERAL FAMILIARIZATION COURSEDuvanRamosGarzon1
AIRCRAFT GENERAL
The Single Aisle is the most advanced family aircraft in service today, with fly-by-wire flight controls.
The A318, A319, A320 and A321 are twin-engine subsonic medium range aircraft.
The family offers a choice of engines
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Courier management system project report.pdfKamal Acharya
It is now-a-days very important for the people to send or receive articles like imported furniture, electronic items, gifts, business goods and the like. People depend vastly on different transport systems which mostly use the manual way of receiving and delivering the articles. There is no way to track the articles till they are received and there is no way to let the customer know what happened in transit, once he booked some articles. In such a situation, we need a system which completely computerizes the cargo activities including time to time tracking of the articles sent. This need is fulfilled by Courier Management System software which is online software for the cargo management people that enables them to receive the goods from a source and send them to a required destination and track their status from time to time.
1. PRESENTED BY
VAISHALI.K
M.Tech (ECE) - Ist yr
21304023
DEPARTMENT OF ELECTRONICS & COMMUNICATION
ENGINEERING
PONDICHERRY UNIVERSITY
SUBMITTED TO
Dr.R.NAKKERAN,
Head of the department,
Dept.Of Electronics Engineering
3. INTRODUCTION
A heterodyne is a signal frequency that is
created by combining or mixing two other
frequencies using a signal processing
technique called heterodyning.
Heterodyning is used to shift one frequency
range into another, new frequency range, and
is also involved in the processes
of modulation and demodulation.
The two input frequencies are combined in
a nonlinear signal-processing device such as
a vacuum tube, transistor, or diode, usually
called a mixer.
3
4. INTRODUCTION
In coherent detection the local carrier generated at the receiver is
phase locked with the carrier at the transmitter.
Hence it is also called synchronous detection.
In non coherent detection the local carrier generated at the
receiver not be phase locked with the carrier at the transmitter.
Hence it is also called asynchronous detection.
4
5. COHERENT DETECTION
In optical fiber communication the term coherent refers to any
technique which employs non linear mixing between two optical
waves.
In this technique gain is provided to the incoming optical signal
by combining or mixing it with locally generated continuous
wave (CW) optical field.
The device used for creating the CW signal is a narrow line width
laser called a local oscillator (LO).
5
7. MATHEMATICAL ANALYSIS OF
COHERENT DETECTION
Let us consider the electric field of the optical signal to be plane
wave having the form
To send information one can modulate the amplitude, frequency
or phase of the signal carrier.
Thus one of the following three modulation techniques can be
implemented
ASK
FSK
PSK
7
8. MATHEMATICAL ANALYSIS OF
COHERENT DETECTION
In direct detection system the electrical signal coming into the
transmitter amplitude modulates the optical power level of the
light source.
Thus the optical power is proportional to the signal current level.
At the receiver the incoming optical signal is converted directly
into demodulated electrical output.
This directly detected current is proportional to the intensity Idd
of the optical signal
8
9. MATHEMATICAL ANALYSIS OF
COHERENT DETECTION
Because the response capability of the receiver
If the local oscillator field is
Now the coherent detected output at the receiver is
9
10. MATHEMATICAL ANALYSIS OF
COHERENT DETECTION
Since the optical power P(t) is proportional to the intensity at
the photodetector we have
10
11. HOMODYNE DETECTION
When the signal carrier and local oscillator frequencies are
equal, it is called a homodyne detection.
Homodyne detection brings the signal directly to the baseband
frequency, so that no further electrical demodulation is required.
Homodyne receivers yield the most sensitive coherent system.
It is most difficult to build, since the local oscillator lasers to
have the same frequencies.
In this since
11
12. HETERODYNE DETECTION
In heterodyne detection, the intermediate frequency is nonzero
and an optical phase locked loop is not needed.
In heterodyne detection, the local-oscillator frequency (LO)
ωLO is chosen to differ from the signal-carrier frequency ω0 such
that the intermediate frequency ωIF is in the microwave region
(ωIF = 1 GHz).
Heterodyne receivers are much easier to implement than
homodyne receivers.
In heterodyne detection, 3dB degradation in sensitivity
compared to homodyne detection.
12
13. HETERODYNE DETECTION
Let us consider the output current at the receiver
The receiver output current then contain a dc term given by
The dc current is normally filtered out in the receiver, and IF
current gets amplified. One then recovers the information from
the amplified current using conventional RF demodulation
techniques.
13
15. HETERODYNE DETECTION
Heterodyne detection
Information can be transmitted through amplitude, phase, or
frequency modulation of the optical carrier wave in heterodyne
detections.
Heterodyne detection is used for the construction of Doppler
velocimeters and laser range finders and as well as in
spectroscopy (particular LIDAR systems).
15
17. ADVANTAGES OF HETERODYNE
Direct encoding of the spectrum of the incoming signal over a
given wavelength range.
Signals are down-converted to frequencies where low noise
electronics can be used.
17
18. APPLICATIONS OF HETERODYNE
The heterodyne detection used in radio as they boost the angular
resolution through inter-ferometry.
18