This document proposes a technique called Differential Distributed Space-Time Coding OFDM (D-DSTC OFDM) to address synchronization issues in asynchronous cooperative relay networks. It discusses how conventional distributed space-time coding suffers from inter-symbol interference due to relay synchronization errors. The proposed D-DSTC OFDM approach uses differential encoding, circular time reversal, and OFDM modulation to eliminate the need for channel state information or strict relay synchronization. Simulation results show the BER performance of D-DSTC OFDM degrades gracefully with increasing synchronization errors, outperforming coherent detection schemes. The key advantages and limitations of the D-DSTC OFDM approach are summarized.
Joint blind calibration and time-delay estimation for multiband rangingTarik Kazaz
In this presentation, we focus on the problem of blind joint calibration of multiband transceivers and time-delay (TD) estimation of multipath channels. We show that this problem can be formulated as a particular case of covariance matching. Although this problem is severely ill-posed, prior information about radio-frequency chain distortions and multipath channel sparsity is used for regularization. This approach leads to a biconvex optimization problem, which is formulated as a rank-constrained linear system and solved by a simple group Lasso algorithm.
% This method is general and can be also applied for calibration of sensors arrays and in direction of arrival estimation.
Numerical experiments show that the proposed algorithm provides better calibration and higher resolution for TD estimation than current state-of-the-art methods.
Joint blind calibration and time-delay estimation for multiband rangingTarik Kazaz
In this presentation, we focus on the problem of blind joint calibration of multiband transceivers and time-delay (TD) estimation of multipath channels. We show that this problem can be formulated as a particular case of covariance matching. Although this problem is severely ill-posed, prior information about radio-frequency chain distortions and multipath channel sparsity is used for regularization. This approach leads to a biconvex optimization problem, which is formulated as a rank-constrained linear system and solved by a simple group Lasso algorithm.
% This method is general and can be also applied for calibration of sensors arrays and in direction of arrival estimation.
Numerical experiments show that the proposed algorithm provides better calibration and higher resolution for TD estimation than current state-of-the-art methods.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Slides of a talk at CMU Theory lunch (http://www.cs.cmu.edu/~theorylunch/20111116.html) and Capital Area Theory seminar (http://www.cs.umd.edu/areas/Theory/CATS/#Grigory).
Using Chebyshev filter design, there are two sub groups,
Type-I Chebyshev Filter
Type-II Chebyshev Filter
The major difference between butterworth and chebyshev filter is that the poles of butterworth filter lie on the circle while the poles of chebyshev filter lie on ellipse.
Design limitations and its effect in the performance of ZC1-DPLLIDES Editor
The paper studies the dynamics of a conventional
positive going zero crossing type digital phase locked loop
(ZC1-DPLL) taking non-ideal responses of the loop constituent
blocks into account. The finite width of the sampling pulses
and the finite propagation delay of the loop subsystems are
properly modeled mathematically and the system dynamics is
found to change because of their influence considered
separately. However, when these two are taken simultaneously,
the system dynamics can be made nearly equivalent to that of
the ideal system. Through an extensive numerical simulation
a set of optimum parameters to overcome design limitations
have been obtained.
EE402B Radio Systems and Personal Communication Networks-Formula sheetHaris Hassan
Programmes in which available:
Masters of Engineering - Electrical and Electronic
Engineering. Masters of Engineering - Electronic
Engineering and Computer Science. Master of Science -
Communication Systems and Wireless Networking.
Master of Science - Smart Telecom and Sensing
Networks. Master of Science - Photonic Integrated
Circuits, Sensors and Networks
To enable an extension of knowledge in fundamental data communications to radio communications and networks widely adopted
in modern telecommunications systems. To provide understanding of radio wave utilisation, channel loss properties, mobile
communication technologies and network protocol architecture applied to practical wireless systems
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Slides of a talk at CMU Theory lunch (http://www.cs.cmu.edu/~theorylunch/20111116.html) and Capital Area Theory seminar (http://www.cs.umd.edu/areas/Theory/CATS/#Grigory).
Using Chebyshev filter design, there are two sub groups,
Type-I Chebyshev Filter
Type-II Chebyshev Filter
The major difference between butterworth and chebyshev filter is that the poles of butterworth filter lie on the circle while the poles of chebyshev filter lie on ellipse.
Design limitations and its effect in the performance of ZC1-DPLLIDES Editor
The paper studies the dynamics of a conventional
positive going zero crossing type digital phase locked loop
(ZC1-DPLL) taking non-ideal responses of the loop constituent
blocks into account. The finite width of the sampling pulses
and the finite propagation delay of the loop subsystems are
properly modeled mathematically and the system dynamics is
found to change because of their influence considered
separately. However, when these two are taken simultaneously,
the system dynamics can be made nearly equivalent to that of
the ideal system. Through an extensive numerical simulation
a set of optimum parameters to overcome design limitations
have been obtained.
EE402B Radio Systems and Personal Communication Networks-Formula sheetHaris Hassan
Programmes in which available:
Masters of Engineering - Electrical and Electronic
Engineering. Masters of Engineering - Electronic
Engineering and Computer Science. Master of Science -
Communication Systems and Wireless Networking.
Master of Science - Smart Telecom and Sensing
Networks. Master of Science - Photonic Integrated
Circuits, Sensors and Networks
To enable an extension of knowledge in fundamental data communications to radio communications and networks widely adopted
in modern telecommunications systems. To provide understanding of radio wave utilisation, channel loss properties, mobile
communication technologies and network protocol architecture applied to practical wireless systems
Parallel Interference Cancellation in beyond 3G multi-user and multi-antenna ...David Sabater Dinter
In the present thesis, the concept for beyond 3G mobile radio systems is described. A service area concept is introduced in order to combat the performance limiting interferences present in the cellular mobile communication systems, with each service area consisting of a various simultaneously active mobile terminals, a number of fixed access points and a central unit per- forming signal processing. About uplink transmission, the main characteristic of this service area system is that with the aid of joint detection of the transmit signals from the mobile ter- minals performed at uplink transmission, all interferences between the simultaneously active mobile terminals using the same bandwidth is drastically reduced. Moreover the use of OFDM subcarrierwise in the described service area based system allows for intersymbol interference free communication and for simple equalization in the frequency domain.
Through this subcarrierwise equalization the service area based system is equivalent with a number of smaller parallel systems, a fact that affects in a reduced computational complexity in the case of optimum multiuser operating with the maximum likehood principle and subop- timum linear detector zero-forcing. In this thesis the parallel interference cancellation detector is introduced, according to which the multi access interference is iteratively reconstructed and subtracted from the received signal. Parallel interference cancellation detector is compared in terms of performance with suboptimum linear detector, due to the reduced computational com- plexity.
Using standardized COST 207 channel models, the performance of parallel interference can- cellation detector compared with suboptimum linear detector has been investigated for a frozen channel, with the same snapshot using the same parameters of the channel, as well as for a number of system loads. A fact that can be observed in simulations results is that parallel in- terference cancellation detectors could achieve the same performance with a reduction of the complexity as suboptimum linear detector zero-forcing in the case of no estimate refinement and with estimate refinement by hard quantization depending on the load system. With esti- mate refinement by soft quantization the performance of the parallel interference cancellation detector is improved, having better performance than zero-forcing detector in cases with nor- mal load. Moreover with the improvement raised in this thesis, in this normal system load, the performance is more improved. On the other hand in the case of full load system, the PIC detector can not substract all the multi access interference producing error flow, this thing is not too important taking in account that the fully loaded system case should not be never present.
This three day course is intended for practicing systems engineers who want to learn how to apply model-driven systems Successful systems engineering requires a broad understanding of the important principles of modern spacecraft communications. This three-day course covers both theory and practice, with emphasis on the important system engineering principles, tradeoffs, and rules of thumb. The latest technologies are covered. <p>
4 matched filters and ambiguity functions for radar signals-2Solo Hermelin
Matched filters (Part 2of 2) maximizes the output signal-to-noise ratio for a known radar signal at a predefined time.
For comments please contact me at solo.hermelin@gmail.com.
For more presentations on different subjects visit my website at http://www.solohermelin.com.
Differential Amplify-and-Forward Relaying in Time-Varying Rayleigh Fading Cha...mravendi
Differential Amplify-and-Forward Relaying in Time-Varying Rayleigh Fading Channels
This paper considers the performance of differential
amplify-and-forward (D-AF) relaying over time-varying Rayleigh
fading channels. Using the auto-regressive time-series model to
characterize the time-varying nature of the wireless channels,
new weights for the maximum ratio combining (MRC) of the
received signals at the destination are proposed. Expression for
the pair-wise error probability (PEP) is provided and used to
obtain an approximation of the total average bit error probability
(BEP). The obtained BEP approximation clearly shows how
the system performance depends on the auto-correlation of the
direct and the cascaded channels and an irreducible error floor
exists at high signal-to-noise ratio (SNR). Simulation results also
demonstrate that, for fast-fading channels, the new MRC weights
lead to a better performance when compared to the classical
combining scheme. Our analysis is verified with simulation results
in different fading scenarios.
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.
CW RADAR, FMCW RADAR, FMCW ALTIMETER, AND THEIR PARAMETERSveerababupersonal22
It consists of cw radar and fmcw radar ,range measurement,if amplifier and fmcw altimeterThe CW radar operates using continuous wave transmission, while the FMCW radar employs frequency-modulated continuous wave technology. Range measurement is a crucial aspect of radar systems, providing information about the distance to a target. The IF amplifier plays a key role in signal processing, amplifying intermediate frequency signals for further analysis. The FMCW altimeter utilizes frequency-modulated continuous wave technology to accurately measure altitude above a reference point.
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.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Overview of the fundamental roles in Hydropower generation and the components involved in wider Electrical Engineering.
This paper presents the design and construction of hydroelectric dams from the hydrologist’s survey of the valley before construction, all aspects and involved disciplines, fluid dynamics, structural engineering, generation and mains frequency regulation to the very transmission of power through the network in the United Kingdom.
Author: Robbie Edward Sayers
Collaborators and co editors: Charlie Sims and Connor Healey.
(C) 2024 Robbie E. Sayers
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.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
3. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Cooperative Communications
Phase I: Source transmits, Relays listen
Phase II: Relays re-broadcast their received signal to
Destination
Virtual antenna array, improving diversity
q1
q2
qR
g1
g2
gR
Source
Destination
Relay 1
Relay 2
Relay R
3
4. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Relay Strategies
Repetition-based
Phase I Phase II
Source broadcasts Relay 1 forwards Relay 2 forwards Relay i forwards Relay R forwards
Time
Distributed space-time based
Phase I Phase II
Source broadcasts Relays forwards simultaneously
Time
Which one simpler to implement?
Which one bandwidth efficient?
4
5. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
System Model
All channels are Rayleigh flat-fading
Phase I: Source transmits [s1, s2], (differential encoded)
Relays receive [x11, x12] and [x21, x22]
Phase II: Relays re-transmit [x11, x12] and [−x∗
22, x∗
21]
[s1, s2]
[x11, x12]
[−x∗
22, x∗
21]
[y1, y2]
q1
q2
g1
g2Source
Destination
Relay 1
Relay 2
5
6. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Synchronized Relay Networks
Perfect relays synchronization
y1 = g1x11 − g2x∗
22 + n1
y2 = g1x12 + g2x∗
21 + n2
y1
y2
= A P0
s1 −s∗
2
s2 s∗
1
q1g1
q∗
2g2
+
w1
w2
(1)
RX signal from Relay 1
RX signal from Relay 2
Block k
x11 x12
−x∗
22 x∗
21
6
9. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Asynchronous Relay Networks
Effect of synchronization error on conventional decoder (CDD)
0 5 10 15 20 25 30
10
−4
10
−3
10
−2
10
−1
10
0
CDD, τ=0
CDD, τ=0.2 Ts
CDD, τ=0.4 T
s
CDD, τ=0.6 T
s
CDD, τ=0.3 T
s
P/N0 (dB)
BER
Figure: BER of D-DSTC using BPSK at various synchronization
errors τ8
10. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Frequency Selective Channels
Flat-fading channel, one tap filter h[k] = h0:
y[k] = h0x[k] + n[k]
Frequency selective channel, multiple taps filter:
h[k] =
L−1
l=0
hl δ[k − l]
y[k] = x ∗ h =
L
l=0
hl x[k − l] + n[k]
Inter Symbol Interference (ISI)
Orthogonal frequency-division multiplexing (OFDM)
9
11. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Point-to-Point OFDM Structure
x = [x1, · · · , xN ], y = [y1, · · · , yN]
yn = Hnxn + nn, n = 1, · · · , N
bits x
ˆx
Add
Remove
Cyclic Prefix
Cyclic Prefix
Modulation
Detection
X Xcp
ISI Channel
YcpYy
DFT
IDFT
Frequency diversity can be achieved by using channel coding
What are drawbacks of OFDM?
10
12. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Simulation Results
5 10 15 20 25 30
10
−4
10
−3
10
−2
10
−1
SNR per bit,[dB]
biterrorprobability
Ncp=0
Ncp=2
Ncp=4
Ncp=6
Ncp=8
theory
Figure: BER of OFDM system over a frequency-selective channel with
four taps, N = 128, using QPSK for different values of cyclic prefix
11
13. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Differential OFDM
v = [v1, · · · , vN ], x(k) = [x1, · · · , xN]
Differential Encoding: x
(k)
n = vnx
(k−1)
n , n = 1, · · · , N
Decoding: y
(k)
n = vny
(k−1)
n + wn, n = 1, · · · , N
Requires constant channel over two OFDM blocks, i.e., 2N
symbols
3 dB performance loss compared with coherent detection
12
14. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Simulation Results
5 10 15 20 25
10
−3
10
−2
10
−1
SNR
BER
Differential OFDM
Coherent OFDM
Figure: BER of Differential and Coherent OFDM system over a
frequency-selective channel with four taps, N = 128, using QPSK
13
15. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Asynchronous vs. Frequency Selectivity
Relay 2 is late:
y1 = g1x11 − αg2x∗
22 + βg2x∗
21
(k−1)
+ n1
y2 = g1x12 + αg2x∗
21 − βg2x∗
22 + n2
Relay 1-Destination channel: flat-fading, g1
Relay 2-Destination channel: can be assumed as frequency
selective, [αg2, βg2]
What is the difference between [αg2, βg2] and an actual
frequency-selective channel?
Block (k)Block (k − 1)
τ
x11 x12
−x∗
22 x∗
21
x11 x12
−x∗
22 x∗
21
14
19. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
D-DSTC OFDM: Pros and Cons
No channel information required
No delay between relays required
Higher delays: cyclic prefix
Complexity similar to OFDM, symbol-by-symbol decoding
Channels have to be static over three OFDM blocks=6N
Destination have to wait four OFDM blocks=8N before start
decoding
18
20. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
D-DSTC OFDM: Pros and Cons
No channel information required
No delay between relays required
Higher delays: cyclic prefix
Complexity similar to OFDM, symbol-by-symbol decoding
Channels have to be static over three OFDM blocks=6N
Destination have to wait four OFDM blocks=8N before start
decoding
18
21. Introduction
D-DSTC
OFDM Systems
D-DSTC OFDM
Summary
Simulation Results
P0 = P/2, Pr = P/4, A = Pr /(P0 + N0)
0 5 10 15 20 25 30
10
−3
10
−2
10
−1
10
0
Differential, τ=0
Coherent, τ=0
Differential, τ=0.4
Differential, τ=0.6
Differential, τ=0.8
P/N0 (dB)
BER
Figure: BER of D-DSTC OFDM, N = 64, one cyclic prefix, using
BPSK for different sync errors τ19