This paper is a thesis in which a signal level simulator in uplink is implemented according to the physical layer specification of the IMT-2000 WCDMA system.
Abstract This paper explains that the goal for the next generation of mobile communications system is to seamlessly integrate a wide variety of communication services such as high speed data, video and multimedia traffic as well as voice signals. The author reports that, for the analysis for this thesis, an analytical WCDMA system through the use of linear algebra techniques is utilized along with a simulation tool in Matlab, which was developed for this work. The paper demonstrates performance improvement due to processing gain, PN sequence, RAKE receiver, smart antenna and multiuser detection, which are compared with respective theories. The paper includes many tables, charts, illustrations, equations and all the source codes.
Table of Contents:
Introduction to WCDMA
Introduction
Applicable Techniques to Enhance System Performance
Spreading
Multipath Diversity
Multiuser Detection
Smart Antenna Outline of This Thesis
Abbreviations
List of Symbols
Analytical WCDMA System Model
Introduction
CDMA System Model for the Uplink
Mobile Radio Channel Model
Discrete Time Base Band Uplink Model
Synchronous CDMA
Asynchronous CDMA
Single Path Model
Multipath Model
Multiple Antenna Model
Conclusion
Spreading in WCDMA
Introduction
Properties of PN Sequence
Spreading and Scrambling in the Uplink of WCDMA
Walsh-Hadamard Codes and Spreading
Gold Codes and Scrambing
Conclusion
RAKE Receiver and Multiuser Detection
Introduction
System Model
The RAKE Receiver
Multiuser Detection
Input Signal Modeling
Optimal Detection
Suboptimal Detection
Decorrelating Detector
Linear Minimum Mean Square Error (MMSE)
Adaptive MMSE Algorithm-RLS Algorithm with Adaptive Memory
Conclusion
Smart Antenna in WCDMA
Types of Smart Antenna Signal Modeling
Beamforming Schemes
Conventional Beamforming
Optimum Beamforming
Adaptive Beamforming
Conclusion
Simulation
System Setup
Channel
System Performance
Performance without RAKE Receiver and with RAKE Receiver
Performance of 1-D RAKE Receiver with EGC or Selection Combining
Performance of 1-D RAKE Receiver with Decorrelating Detector and MMSE
Performance with PN Sequence and Random Sequence
Performance with Processing Gain
Performance with Adaptive MUD- RLS Algorithm with Adaptive Memory
Performance with Smart Antenna Conclusion
Conclusion
Summary of Research
Future Work
From the Paper "The despreaded sequence is forwarded to the multiuser detector unit. In this unit, performance enhancing signal processing such as beam forming, RAKE combining including channel estimation, antenna diversity combining, multiuser detection and error control decoding can be included. If perfect channel information is available, beam forming, RAKE and antenna diversity combining merely represent linear transformations to obtain a minimal set of sufficient statistics. From the fundamental digital communication theory, this is in fact equivalent to filtering matched to the received waveform in order to maximise the signal-to-noise ratio (SNR)."
Tags: spreading, scrambling, gain, rake, detection
Abstract Long thought of as a simple conjuring trick, an optical illusion, or something only deep meditation could bring about, levitation is now gaining validation and respect as a legitimate scientific event. Researchers in the field of levitation are now discovering that levitation is brought about by certain magnetic forces which are focused through the use of a human conduit or "antenna." This paper looks at techniques for achieving levitation and the scientific principles behind the phenomenon.
Abstract This paper discusses cell towers and antennas and questions their safety in the community. The paper confirms that the number of cell sites has increased over the years in proportion to the expanding number of subscribers. These tower structures are erected on various locations such as parks, schools and fire houses. The paper considers if these towers really put us at risk and states that according to the Food and Drug Administration Act, exposure to cellphone radiation on the ground is significantly weaker than exposure on the direct path of the transmitted signal of the antenna. This exposure is several thousand of times less than the minimum safety levels recommended by expert studies. Thus the paper confirms that civilian exposure to cellphone radiation is well within the safety margins.
From the Paper "Electromagnetic radiation, composed of electric and magnetic energy moving at the speed of light, is the one feared by most people. The electromagnetic spectrum is a wide range of electromagnetic signals ranging from high-frequency x-rays and gamma rays to low-frequency radio waves. Your cellphone's electromagnetic radiation has a 3kHz-300GHz frequency. This falls just after the very low frequency like your computers and before or just the same frequency as your everyday microwave oven. And still the radiation coming from the sun poses more danger than your cellphone."
Abstract This paper describes the Monarch Butterfly in great detail, such as why does it have the bright colors and what do they mean? It states that the life of a Monarch Butterfly is quite complicated. The Monarch Butterfly is watched closely to prevent it from being extinct.
Table of Contents
Butterflies are Invertebrates
The Monarch"Danaus Plexippus
The Life Cycle of a Monarch
Lincoln Brower and the Monarch Butterfly
Brad Darrach and the Monarch Butterfly
The Monarch Butterfly Will It Be an Endangered Species"
The El Rosario Monarch Reserve
More Monarch Butterflies Killed and Solutions
From the Paper "The butterfly comes from the Lepidoptera, which is a Greek word meaning that the wings are covered in scales. Butterflies have compound eyes on either side of the head. The eyes are and made up of thousands of lensed-eyes called "ommatidia". They are not able to see fine detail, but are able to detach if they have a predator."
Abstract As technology becomes increasingly user-friendly and focused on the consumer, it is evident that users have become more dependent on wireless technological devices as mechanisms that promote convenience, survival and economic prosperity. This study demonstrates the absolute importance of personal and business forms of wireless technology in today's increasingly complex society. Various books, periodicals and research journal articles are used to summarize the history of communications leading up to the arrival of wireless technology and also provide a detailed description of the most commonly used wireless devices in personal and professional living. Furthermore, a list of common terms frequently used in wireless technology is addressed. In addition, personal experiences demonstrate the significance of wireless devices in daily living. Finally, the researcher provides an analysis of the future outlook for wireless technology and its continued significance in all areas of livelihood, particularly in advanced industrial countries. The paper includes tables.
Table of Contents:
Chapter 1: Introduction
The Problem
Purpose of the Study
Importance of the Study
Scope of the Study
Rationale of the Study
Definition of Terms
Overview of the Study
Chapter 2: Review of the Related Literature
Introduction
Origin of Wireless Networking Technology
What is Wireless Technology
Applications for Wireless Technology
Cellular Technology
Wireless Security
User Perceptions of Wireless Technology
The Future of Wireless Technology
The Impact of Wireless Technology on Global Communications
Summary of Chapter 2
Chapter 3: Methodology
Approach
Data Gathering Method
Database of Study
Validity of Data
Originality & Limitations of Data
Summary of Chapter 3
Chapter 4: Data Analysis
Data Analysis
Chapter 5: Summary, Conclusions and Recommendations
Summary
Conclusions
Recommendations
Bibliography
From the Paper "Wireless networks provide users with an effective means of communication with a corporate network or a personal user interface in the home that permits access to the Internet through such devices as laptop computers, cellular phones, and personal digital assistants. Following the development of the IEEE 802.11b standard or WiFi (Wireless Fidelity), countless wireless network cards and wireless access points with data rates up to 54 million bits per second have been manufactured and marketed for sale across the globe (Blosser, 2002). In addition, cellular technology has developed 2.5G systems that add digital capability to existing digital systems. Finally, wireless local area networks (WLANs) are one of the fastest growing wireless segments in the industry. The IEEEE 802.11b WLAN connections are very common in home networking technologies and wireless Internet access points (Frenzel, 2002)."
This paper discusses Radio Frequency Identification Devices (RFID), an automated identification and data collection technology consisting of tags containing chips for storing data and an antenna for transmitting data through radio waves.
3,150 words (approx. 12.6 pages), 14 sources, MLA, $ 91.95
Abstract This paper explains that RFID chips can be attached, often without notice, to all sorts of products, such as clothing and books, and can be use to monitor and control the supply chain in ways similar to the bar code, which the RFID is being developed to replace. The author points out that some examples of the consumer use of the RFID are in a library where the reader need only to walk in front of a shelf and can immediately see on a screen a list of all the books and their contents. For another example, parents in amusement parks can locate their children by putting a RFID on their children and then locating them on a special "kidspotter" map of the park. The paper stresses that, despite the clear advantages of RFID, there is a concern among privacy activists because RFID tags, so small that they can go undetected, can be embedded in any product or article of clothing and even under the skin of a person and then can be used to record information about their activities, tracking anyone with a tag on them.
Table of Contents
History
Beneficial Social Impact
Deleterious Social Impact or Potentially Dangerous Social Impact
Personal Privacy
Information Security
Analysis of Social Impact
Future Impact of the Technology
From the Paper "While in the 1980's RFID was primarily used for commercial applications, the 1990s saw RFID enter the consumer market. Toll systems throughout the US and Europe became widespread and started gaining major use. Toll systems were adopted by Kansas, Oklahoma, Georgia, Maine, and New York, Massachusetts, and quite a few other states. Standardization became a big issue with all these systems, leading to the Title 21 standard and the EZ-Pass Interagency Group, both of which were formed in an effort to provide consistent toll standards in different regions of the US. Payment and access systems were developed, such as the speedpass payment system used by Mobile gas stations, various skipass systems and gated community access setups. Automobile related RFID systems also were implemented in larger scale including remote entry and ignitions systems."
Abstract This paper explains that the advantage of satellite technology over direct wire transmission is obvious: Satellites can transmit data at light speed anywhere on the planet without impractical and costly wiring. The author writes about three general types of satellites, classified by the type of orbit they follow: (1) Geosynchronous orbit, GEO, in which the satellite's orbit is synchronized with the rotation of the earth; (2) Medium earth orbit, MEO, which gets closer to the earth because it utilizes an elliptical orbit, and (3) Low earth orbit, LEO, the most recent type of satellite, which are located approximately 450 miles above the surface of the Earth, and can be used for portable phones with smaller antennas. The paper relates that the attributes of satellite systems make them valuable for varying internet applications, but the primary difficulty now is congestion and associated delays; however, when LEO satellites become more abundant and dependable, it is probable that the amount of internet traffic, which LEO satellites can handle, will increase.
From the Paper "Fortunately, as the technologies improve-in both the internet and satellites-prices fall and these tools become more widely available. "Thanks to both the rapid deployment of the internet, and advances in satellite technology, the market for broadband satellite services is poised for substantial growth in the coming decade." Particularly, satellites in GEO orbits are being improved to be capable of relaying more information; with less latency and interference. Also, LEO satellites are being employed because they do not require the bulky equipment needed to improve the existing GEO satellites. Additionally, with the advent of dense wavelength division multiplexing along fiber optic cables, broadband capabilities should become exponentially greater."
Abstract The paper begins by explaining basically what radar is and for what it's used. Then the paper recounts the history of radar's development, both theoretically and practically. From the history of radar the paper returns to the question of how it works, but analyzes the physics in depth, and breaks down the operation of each of a radar system's components. The paper finishes with a review of modern applications of different types of radar systems.
Table of Contents:
The History of Radar
Robert H. Rines - American Father of Radar
How Radar Works
The Radar Transmitter System
The Oscillator
The Modulator
The Transmitter
The Antenna Types of Radar
Simple Pulse Radar
Continuous Wave Radar
Phased-Array Radar
Secondary Radar
Modern Radar
References
From the Paper "Parallel developments occurred in a number of countries. The highest frequency at which then-current technology allowed substantial power to be generated was about 30MHz, the top end of the HF band. UK radar development proceeded rapidly from 1935 so that by 1937 the first operational (HF) radars of the Chain Home series were demonstrated. These frequencies were in place at the outbreak of World War II and played a decisive role in the air defence of Britain during the War. Wartime radar development quickly moved on to shorter wavelengths as devices were developed to allow generation and control of the power, but the Chain Home radars remained in service, as originally installed. The Chain Home radars, operating between 25 to 30MHz, on occasions indicated returns from extreme ranges, due to ionospheric reflection beyond the horizon. But they were intended as line-of-sight radars and long-range returns from the distant ground via an ionospheric reflection were generally only a source of confusion. During the War some attempts were made to use the ionospherically propagated signal for long range detections of convoys but no success was achieved (or could be expected) and tests were dropped."
Abstract The paper explains how radio frequency identification (RFID) is an automatic identification method that relies on storing and remotely retrieving data using RFID tags, or transponders. The tags contain silicon chips and antennas that allow it to receive and respond to radio-frequency queries from an RFID transceiver. The paper discusses the history of RFID and the differences between semi-passive RFID tags and passive tags. The paper shows how the promise of being able to track product movement in real time is very appealing. The paper discusses how RFID-tagged items are better than bar-codes; they hold more information, can be read in bulk and do not require direct line of sight with the RFID reader to transfer information.
From the Paper "The RFID predecessor dates back to 1945, when Leon Theremin invented an espionage tool for the Soviet government (RFID). Although this was a covert listening device and in an identification tag, it is the first known device and is considered a predecessor to RFID technology (RFID). The IFF transponder was invented by the British in 1939 and was used by the allies in World War II to identify airplanes (RFID). Harry Stockman, in his landmark 1948 paper, Communication by Means of Reflected Power, predicted that "considerable research and development work has to be done before the remaining basic problems in reflected-power communication are solved, and before the field of useful application is explored" (RFID). It took thirty years of advances in numerous fields before RFID became a reality (RFID)."
Abstract This paper takes a look at the danger of the radiation emitted from a cell phone in use. According to the paper, some of the potential health hazards that may evolve from cell phone use include noise in the ear, memory loss, headaches, malignant brain tumors and DNA damage.
Outline:
I.The Silent Enemy
Cover-up?
Radiation
II.Concerns for All Ages
In Light on Concerns
III. The Big Question
The Privilege to Listen
From the Paper "Even though cell phones and fortune cookies may not initially appear to have a common thread, the concept that connects them is that those who market cell phones, in a similar sense, do not usually consider what happens to those who purchase and use cell phones. In the study completed by Salford et al funded by a grant from the Swedish Council for Work Life Research. Completed during 2002, the authors examine potential risks of radio-frequency electromagnetic fields for the human body. Their previous studies posit ". . . weak pulsed microwaves give rise to a significant leakage of albumin through the blood-brain barrier."
Abstract The paper explains the fundamentals of the radio frequency identification (RFID) technology. The paper explores the two types of RFID tags; active and passive. The paper discusses RFID's applications in the supply chain and relates that with the software industry losing approximately forty per cent of its global revenues every year due to counterfeiting and the widespread abuses of music distribution, the use of secure RFID tags seems inevitable.
Outline:
Fundamentals of Radio Frequency Identification
Exploring the type of RFID Tags
RFID's Applications in the Supply Chain
From the Paper "RFID stands for Radio Frequency Identification Code, and is part of the larger Auto-ID technology family, and is a technology that uses radio-frequency waves to transfer data between a reader and a movable item to identify, categorize, track and monitor products. RFID tags are comprised of microchips with antennas that broadcast their status to remote readers. As this technology relies of radio frequencies to communicate, no line of sight is required the movement of products throughout a warehouse is much more efficient."
