The document contains information about the course EC6501 Digital Communication including the units covered in the course and their brief descriptions. It discusses topics like sampling and quantization, waveform coding, baseband transmission, digital modulation schemes and error control coding. It provides the course outcomes listing the highest cognitive level for each outcome. The subsequent sections provide more details about digital modulation formats including ASK, PSK, FSK and their generation and detection. It also discusses coherent and non-coherent receivers along with their probability of error analysis.
UNIT III BASEBAND TRANSMISSION
Properties of Line codes- Power Spectral Density of Unipolar / Polar RZ & NRZ – Bipolar NRZ - Manchester- ISI – Nyquist criterion for distortionless transmission – Pulse shaping – Correlative coding - Mary schemes – Eye pattern – Equalization
Base band transmission
*Wave form representation of binary digits
*PCM, DPCM, DM, ADM systems
*Detection of signals in Gaussian noise
*Matched filter - Application of matched filter
*Error probability performance of binary signaling
*Multilevel base band transmission
*Inter symbol interference
*Eye pattern
*Companding
*A law and μ law
*Correlation receiver
UNIT III BASEBAND TRANSMISSION
Properties of Line codes- Power Spectral Density of Unipolar / Polar RZ & NRZ – Bipolar NRZ - Manchester- ISI – Nyquist criterion for distortionless transmission – Pulse shaping – Correlative coding - Mary schemes – Eye pattern – Equalization
Base band transmission
*Wave form representation of binary digits
*PCM, DPCM, DM, ADM systems
*Detection of signals in Gaussian noise
*Matched filter - Application of matched filter
*Error probability performance of binary signaling
*Multilevel base band transmission
*Inter symbol interference
*Eye pattern
*Companding
*A law and μ law
*Correlation receiver
Frequency-Shift Keying, also known as FSK is a type of digital frequency modulation. It is also often called as binary frequency shift keying or BFSK
Similar to analog FM, it is a constant-amplitude angle modulation.
This presentation will discuss the concepts behind FSK
The Presentation is as per the syllabus of the subject ”Digital Communication” of B.E. VIth Semester of Sant Gadge Baba Amravati University, Maharashtra, India
Contents are
Digital Communication System
Line Coding
Scrambling
Comparative Study and Performance Analysis of different Modulation Techniques...Souvik Das
A comparative study and performance analysis of different modulation
techniques which shows graphically and comparative results Channel Noise
with Bit Error Rate of ASK, FSK, PSK and QPSK.
Frequency-Shift Keying, also known as FSK is a type of digital frequency modulation. It is also often called as binary frequency shift keying or BFSK
Similar to analog FM, it is a constant-amplitude angle modulation.
This presentation will discuss the concepts behind FSK
The Presentation is as per the syllabus of the subject ”Digital Communication” of B.E. VIth Semester of Sant Gadge Baba Amravati University, Maharashtra, India
Contents are
Digital Communication System
Line Coding
Scrambling
Comparative Study and Performance Analysis of different Modulation Techniques...Souvik Das
A comparative study and performance analysis of different modulation
techniques which shows graphically and comparative results Channel Noise
with Bit Error Rate of ASK, FSK, PSK and QPSK.
The paper discuses about the performance of digital modulation schemes – BPSK, QPSK and QAM using
MATLAB. The performance of these schemes is evaluated by finding the bit error rate (BER) on AWGN and
Rayleigh channels. Initially a MATLAB code is generated and the performance of these modulation schemes
BPSK,QPSK and QAM is evaluated by finding BER and signal to noise ratio over AWGN and Rayleigh fading
channels. Later a simulation model is created using Simulink for these modulation schemes and its performance is
evaluated on AWGN channel.
Alberto Morello and Vittoria Mignone
DVB-S2 is the second-generation specification for satellite broadcasting – developed by the DVB (Digital Video Broadcasting) Project in 2003. It benefits from more recent developments in channel coding (LDPC codes) combined with a variety of
modulation formats (QPSK, 8PSK, 16APSK and 32APSK).
The several assets for high-speed data transmission over wireless uses the Orthogonal Frequency Division
Multiplexing (OFDM) as it is a multicarrier transmission scheme. A large number of narrow bandwidth carriers is
therefore adopted by the OFDM. Individually for an OFDM, each subcarrier is attenuated under the frequency-selective
and fast fading channel, therefore the resulting gain is high attenuation which leads to poor performance of all OFDM
subcarriers if the same fixed transmission scheme are used. Thus the main goal of the indicated paper is to grab an
understanding of the inequality between fixed & adaptive modulations schemes as the introduction of the adaptive
modulation. The need for the above system is to make use of the speaker's voice to check their character and control
approach to administrations, for example, voice dialing data administrations, voice send, and security control for secret
data. The performance of paperwork basically states that implementation of adaptive modulation is done into blocks of
adjacent subcarriers which is the result of dividing whole subcarriers. Therefore the equivalent modulation scheme which
is the calculation of average instantaneous signal to noise (SNR) is exercised to entire subcarriers of the equal block. The
OFDM system average bit error rate (BER) performance is observed here under fixed modulation and adaptive
modulation, and these modulation techniques are recorded by accepting the different inverse fast Fourier transforms
(IFFT) size and uncomplicated adaptive Quadrature amplitude modulation (QAM) strategy. The simulation in MATLAB
shows the results as the performance of fixed modulation is inferior to that of the BER performance of OFDM system
using adaptive modulation. The prospective adaptive modulation and coding Technique uses OFDM to manage the fixed
BER under changing the channel.
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...IJECEIAES
This paper addresses the performance analysis of OFDM transmission system based on coherent detection over high speed long haul optical links with high spectral efficiency modulation formats such as Quadrature Amplitude Modulation (QAM) as a mapping method prior to the OFDM multicarrier representation. Post compensation is used to compensate for phase noise effects. Coherent detection for signal transmitted at bit rate of 40 Gbps is successfully achieved up to distance of 3200km. Performance is analyzed in terms of Symbol Error Rate and Error Vector Magnitude by varying Optical Signal to Noise Ratio (OSNR) and varying the length of the fiber i.e transmission distance. Transmission performance is also observed through constellation diagrams at different transmission distances and different OSNRs.
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Yayah Zakaria
This paper addresses the performance analysis of OFDM transmission system based on coherent detection over high speed long haul optical links with high spectral efficiency modulation formats such as Quadrature Amplitude Modulation (QAM) as a mapping method prior to the OFDM multicarrier representation. Post compensation is used to compensate for
phase noise effects. Coherent detection for signal transmitted at bit rate of 40 Gbps is successfully achieved up to distance of 3200km. Performance is analyzed in terms of Symbol Error Rate and Error Vector Magnitude by varying Optical Signal to Noise Ratio (OSNR) and varying the length of the fiber i.e transmission distance. Transmission performance is also observed through constellation diagrams at different transmission distances and
different OSNRs.
PERFORMANCE EVALUATION OF BER FOR AWGN, AWGN MULTIPATH AND RAYLEIGH FADING CH...IJEEE
The objectives of this paper are to study, analyze and evaluate the performance of BER (Bit Error Rate) in mobile multipath fading propagation channel. The parameters which are considered for the performance evaluation are AWGN, AWGN Multipath, Rayleigh fading channel and Hadamard code generator.
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.
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
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Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
Democratizing Fuzzing at Scale by Abhishek Aryaabh.arya
Presented at NUS: Fuzzing and Software Security Summer School 2024
This keynote talks about the democratization of fuzzing at scale, highlighting the collaboration between open source communities, academia, and industry to advance the field of fuzzing. It delves into the history of fuzzing, the development of scalable fuzzing platforms, and the empowerment of community-driven research. The talk will further discuss recent advancements leveraging AI/ML and offer insights into the future evolution of the fuzzing landscape.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
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.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
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.
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.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Design and Analysis of Algorithms-DP,Backtracking,Graphs,B&B
Dc unit iv
1. RMK COLLEGE OF ENGINEERING & TECHNOLOGY
RSM NAGAR , PUDUVOYAL-601206
EC6501 DIGITAL
COMMUNICATION
DEPARTMENT OF ELECTRONICS AND
2. UNIT I SAMPLING & QUANTIZATION
Low pass sampling – Aliasing- Signal Reconstruction-Quantization -
Uniform & non-uniform quantization - quantization noise - Logarithmic
Companding of speech signal- PCM - TDM
UNIT II WAVEFORM CODING
Prediction filtering and DPCM - Delta Modulation - ADPCM & ADM
principles-Linear Predictive Coding
UNIT III BASEBAND TRANSMISSION
Properties of Line codes- Power Spectral Density of Unipolar / Polar RZ
& NRZ – Bipolar NRZ - Manchester- ISI – Nyquist criterion for
distortionless transmission – Pulse shaping – Correlative coding - Mary
schemes – Eye pattern – Equalization
UNIT IV DIGITAL MODULATION SCHEME
Geometric Representation of signals - Generation, detection, PSD &
BER of Coherent BPSK, BFSK & QPSK - QAM - Carrier Synchronization
- structure of Non-coherent Receivers - Principle of DPSK.
UNIT V ERROR CONTROL CODING
Channel coding theorem - Linear Block codes - Hamming codes - Cyclic
EC6501 DIGITAL COMMUNICATION
9/9/2018 2Department of ECE
3. EC6501 DIGITAL COMMUNICATION
9/9/2018 3
UNIT IV DIGITAL MODULATION SCHEME
Geometric Representation of signals -
Generation, detection, PSD & BER of Coherent
BPSK, BFSK & QPSK - QAM - Carrier
Synchronization - structure of Non-coherent
Receivers - Principle of DPSK.
Department of ECE
4. Course Outcomes
Highest
Cognitive Level
C301.1
Describe the concepts of sampling and
quantization
K2
C301.2
Compare the various source coding
techniques
K2
C301.3
Describe the baseband transmission
schemes
K2
C301.4
Illustrate the different modulation schemes
and equalization techniques
K2
C301.5
Examine the PSD and BER of various
modulation schemes
K3
C301.6 Generate different error control codes K3
9/9/2018 4Department of ECE
5. 9/9/2018 Department of ECE 5
DIGITAL MODULATION -
INTRODUCTION In baseband pulse transmission, the input data is represented
in the form of a discrete PAM signals (line codes). These
signals are transmitted over a low pass channel.
The baseband signals have an adequately large power at low
frequencies. So they can be transmitted over a pair of wires
or coaxial cables.
But it is not possible to transmit the baseband signals over
radio links or satellites because impracticably large
antennas would be required to be used.
Hence, the spectrum of the message signal has to be shifted
to higher frequencies. This is achieved by using the baseband
digital signal to modulate a sinusoidal carrier.
This is called digital carrier modulation or digital passband
communication.
6. 9/9/2018 Department of ECE 6
DIGITAL MODULATION -
INTRODUCTION
The data may represent digital computer outputs or PCM
waves generated by digitizing voice or video channels.
7. 9/9/2018 Department of ECE 7
DIGITAL MODULATION -
INTRODUCTION
GSM-900 uses 890 - 915
MHz to send information from
the Mobile Station to the Base
Transceiver Station (uplink)
and 935 - 960 MHz for the other
direction (downlink), providing
124 RF channels (channel
numbers 1 to 124) spaced at 200
kHz. Duplex spacing of 45
MHz is used
8. 9/9/2018 Department of ECE 8
DIGITAL MODULATION -
INTRODUCTIONTo study
Digital modulation techniques
Noise performance
Spectral properties
Merits
Limitations
Applications
Issues
For the noise analysis, we use signal space approach
9. 9/9/2018 Department of ECE 9
DIGITAL MODULATION -
INTRODUCTIONTwo categories of digital modulation techniques
Coherent Technique - Technique that employs coherent
detection. In coherent detection, the local oscillator generated at
the receiver is phase locked with the carrier at the transmitter.
Thus, the detection is done by correlating received noisy signal
and locally generated carrier. It is a synchronous detection.
Non-coherent Technique – Technique in which the detection
process does not need receiver carrier to be phase locked with
transmitter carrier.
Advantage of Non-coherent Technique - system becomes
simple.
Disadvantage of Non-coherent Technique – error probability
increases (performance is inferior)
10. 9/9/2018 Department of ECE 10
DIGITAL MODULATION
FORMATSTwo types of digital modulation schemes
1. Binary schemes
2. M-ary schemes
In binary schemes, we send any one of the two possible
signals during each signaling interval of duration Tb.
Examples of binary schemes : ASK, FSK and PSK
In M-ary systems, we can send any one of the M-possible
signals during each signaling interval Tb. Examples of M-
ary schemes : M-ary PSK, M-ary FSK, QPSK, MSK,
QASK or QAM etc.
M-ary schemes need less bandwidth as compared to the
binary schemes. But, the error performance of M-ary
schemes is poor as compared to the binary schemes.
11. 9/9/2018 Department of ECE 11
DIGITAL MODULATION -
INTRODUCTION
In transmission and reception of digital carrier signals, we have
to use modulator at the transmitter and a demodulator at the
receiver. Usually both these devices are packed in one unit
called as MODEM for two way communication.
12. 9/9/2018 Department of ECE 12
DIGITAL MODULATION
FORMATS
In digital communications, the modulating wave consists
of binary data or an M-ary encoded version of it.
For the carrier, we use sinusoidal wave
With a sinusoidal carrier, the feature that is used by the
modulator to distinguish one signal from another is a
step change in the amplitude, frequency, or phase of the
carrier.
The result of this modulation process is amplitude-shift
keying , frequency-shift keying , or phase-shift keying
respectively.
PSK and FSK signals are much more widely used than
ASK signals
13. 9/9/2018 Department of ECE 13
DIGITAL MODULATION –
USEFUL TERMS Probability of Error (Pe) – The most important goal of
passband data transmission system is to design the receiver
having minimum value of average probability of error in
presence of additive white Gaussian noise (AGWN). The
value of Pe should be as small as possible.
Power Spectra – It is a graph of power spectral density
plotted on Y axis versus frequency on X axis. It gives us
information about the bandwidth requirement and co-
channel interference.
Bandwidth efficiency – Ratio of the data rate (bits/sec) to
the effectively utilized channel bandwidth. It is denoted by
The communication system should be spectrally efficient.
𝝆 =
𝑹 𝒃
𝑩
𝒃𝒊𝒕𝒔/𝑯𝒛
15. 9/9/2018 Department of ECE 15
ASK/ON-OFF KEYING
MODULATIONAmplitude Shift Keying (ASK) is a form of digital bandpass
modulation technique in which the amplitude of the analog
sinusoidal carrier signal is varied to represent the input
binary data. The frequency and phase of the carrier signal
remains unchanged.
Consider the digital baseband signal (modulating signal)
represented by unipolar NRZ, i.e vm(t)=1 for binary “1” and
vm(t)=0 for binary symbol “0” for entire bit duration Tb, in
the form of on-off signal.
23. 9/9/2018 Department of ECE 23
BINARY PSK (BPSK)
PSK is a form of digital modulation technique in
which the phase angle of the analog sinusoidal
carrier signal “fc” is varied to represent the input
digital data.
However, the amplitude and frequency of the
modulated signal remains constant.
In binary PSK (BPSK), the phase of the sinusoidal
carrier signal is changed by 0o or 180o (π radians)
corresponding to two different voltage levels of
binary modulating signals (1 and 0).
This is the reason that BPSK is called bi-phase
modulation or phase reversal keying.
25. 9/9/2018 Department of ECE 25
COHERENT BINARY PSK
In coherent binary PSK system, the pair of signals,
s1(t) and s2(t), used to represent binary symbols 1
and 0 respectively, are defined by
E=Pt or P=E/t
27. 9/9/2018 Department of ECE 27
* The maximum likelihood decision rule is simply to choose the
message point closest to the received signal point
*
COHERENT
BINARY PSK
29. 9/9/2018 Department of ECE 29
GEOMETRIC INTERPRETATION OF
SIGNALS
(STATE SPACE DIAGRAM/CONSTELLATION DIAGRAM)
A signal constellation diagram refers to a set of possible message
points
30. 9/9/2018 Department of ECE 30
The separation between two message
points is called Euclidean distance
and as it increases, the isolation
between the symbols in BPSK signal
is more and probability of error
decreases.
COHERENT
BINARY PSK
32. 9/9/2018 Department of ECE 32
Pe will decrease as Eb increases
COHERENT BINARY PSK
Noise power spectral density (N0)
33. 9/9/2018 Department of ECE 33
Salient Features of BPSK
BPSK has a very good noise immunity
BPSK has a bandwidth which is lower than that of a BFSK
BPSK has the best performance of all the three digital
modulation techniques in the presence of noise
It yields the minimum value of probability of error
COHERENT BINARY PSK
36. 9/9/2018 Department of ECE 36
COHERENT BINARY FSK(BFSK)
Binary Frequency Shift Keying (BFSK) is a form of digital
modulation technique in which the frequency of the analog
sinusoidal carrier signal “fc” is varied to represent the input digital
data. However the amplitude of the modulated carrier signal
remains constant.
50. 9/9/2018 Department of ECE 50
COHERENT QUADRATURE-
MODULATION TECHNIQUES
IMPORTANT GOAL IN THE DESIGN OF DIGITAL
COMMUNICATION SYSTEM
Provision of reliable performance (very low
probability of error)
Efficient utilization of channel bandwidth
(bandwidth conserving modulation schemes
for the transmission of binary data)
51. 9/9/2018 Department of ECE 51
COHERENT QUADRATURE-
MODULATION TECHNIQUES
Efficient utilization of channel bandwidth
with
Quadrature carrier multiplexing system
1. Quadrature Carrier Signaling Technique
/Quadriphase Shift Keying (QPSK) –
An extension of BPSK
2. Minimum Shift Keying (MSK) –
An extension of BFSK
52. 9/9/2018 Department of ECE 52
COHERENT QUADRATURE-
MODULATION TECHNIQUES
Quadrature carrier multiplexing system
This produces a modulated wave described as follows:
sI(t) - In-phase component of the modulated wave
sQ(t) - Quadrature component of the modulated wave
𝑠 𝑡 = 𝑠𝐼 𝑡 𝑐𝑜𝑠 2𝜋𝑓𝑐 𝑡 − 𝑠 𝑄 𝑡 𝑠𝑖𝑛(2𝜋𝑓𝑐 𝑡)
56. 9/9/2018 Department of ECE 56
QPSK is characterized by having a two-dimensional
constellation (N=2) and four message points (M=4)
QUADRIPHASE SHIFT KEYING
(QPSK)
57. 9/9/2018 Department of ECE 57
QUADRIPHASE SHIFT KEYING
(QPSK)Decision Rule
To realize the decision rule for the detection of the
transmitted data sequence, we partition the signal space
into four region as follows:
The set of points closest to the message point
associated with signal vector s1
The set of points closest to the message point
associated with signal vector s2
The set of points closest to the message point
associated with signal vector s3
The set of points closest to the message point
associated with signal vector s4