Positioning in Wireless Communications Systems

Stephan Sand, Armin Dammann, Christian Mensing

• Publisher: Wiley
• Year: 2014
• Print ISBN: 9780470770641
• eBook ISBN: 9781118694107
• Edition: 1
• Topic: Technology & Engineering
• Subtopic: Mobile & Wireless Communications
• Index: Technology & Engineering

Positioning in Wireless Communications Systems explains the principal differences and similarities of wireless communications systems and navigation systems. It discusses scenarios which are critical for dedicated navigation systems such as the Global Positioning System (GPS) and which motivate the use of positioning based on terrestrial wireless communication systems.

The book introduces approaches for determination of parameters which are dependent on the position of the mobile terminal  and also discusses iterative algorithms to estimate and track the position of the mobile terminal. Models for radio propagation and user mobility are important for performance investigations and assessments using computer simulations. Thus, channel and mobility models are explored, especially focussing on critical navigation environments like urban or indoor scenarios.

Positioning in Wireless Communications Systems examines advanced algorithms such as hybrid data fusion of satellite navigation and positioning with wireless communications and cooperative positioning among mobile terminals.. The performance of the discussed positioning techniques are explored on the basis of already existing and operable terrestrial wireless communication systems such as GSM, UMTS, or LTE and it is shown how positioning issues are fixed in respective standards.

Written by industry experts working at the cutting edge of technological development, the authors are well placed to give an excellent view on this topic, enabling in-depth coverage of current developments.

Key features
• Unique in its approach to dealing with a heterogeneous system approach, different cell structures and signal proposals for future communications systems
• Covers hybrid positioning investigating how GNSS and wireless communications positioning complement each other
• Applications and exploitation of positioning information are discussed to show the benefits of including this information in several parts of a wireless communications system

Chapter 1
Introduction

The determination of position is an art that has fascinated scientists for centuries. First positioning methods were probably developed several millennia ago when people realized the necessity of knowing their position for systematic travel. Orientation at natural landmarks such as mountains, rivers, or coastlines are straightforward methods for that purpose. Early man made landmarks were trails and ways that were often built for trading, for example, the famous Silk Road, which has its origins around 500 B.C., and connected Europe and Eastern Asia. Other man made landmarks are lighthouses. They provide orientation in monotonous environments even at night, for example, for ships relatively close to the coastline. On the high seas, however, landmarks are missing. Keeping track of a journey by measuring direction and velocity, called the dead reckoning method, was the straightforward approach used by early ocean navigators. Celestial navigation is another method that utilizes well-known objects as position references. Measuring the angle of the pole star above the horizon directly provides the latitude. The major problem for a long time has been the determination of the longitude directly related to the exact measurement of time due to the Earth's rotation. As the Earth rotates around

each day, a deviation of 4 s in time keeping results in a position error of

that is 1 nautical mile or 1.852 km at the equator. At that time, the longitude problem was so severe that several prizes were offered for the development of more precise longitude determination methods. In 1714 the British government rewarded £10 000 for a method capable of determining the longitude within a range of 60 nm (nautical miles), £15 000 for a deviation of 40 nm and £20 000 for 30 nm during a six week journey to the West Indies. Famous scientists like Isaac Newton and Edmond Halley proposed and promoted the use of astronomic methods, that is, predictable astronomic occurrences, for time determination. The ‘lunar distance’ relative to a fixed star or the ecliptic of Jupiter's moons are such ideas. The invention of chronometers with sufficient accuracy solved the problem and made astronomical methods needless. In 1761 John Harrison's H.4 marine chronometer, constructed in 1759, showed a time deviation of 5 s during a five-week journey to Jamaica. All methods that at least partially rely on visual observations require clear sight. This limits the usability of these methods to certain times of a day or to good weather conditions. The discovery of radio waves in the late nineteenth century opened the door for the field of radio navigation. Radio beacons take the role of man made landmarks. Radio frequency bands provide a propagation range exceeding that of visible light. Dependent on the frequency band, radio waves are able to travel through clouds or fog, or even propagate as ground waves over a long distance. This solved the range problem even for ground based radio navigation systems. Nowadays, satellite navigation systems provide global coverage with accuracy in the range of meters. Some of the positioning principles, however, remain the same as for traditional landmark or celestial navigation. In particular these are angular methods, where the angle of arrival of radio waves are determined. Today, radio navigation is mainly based on radio propagation time measurements, by which the knowledge of propagation speed (speed of light) provides distance measures related to the radio beacons.

The civil availability of accurate satellite navigation together with chip-sets and navigation receivers for consumer applications have formed the basis of a rapidly growing navigation market in recent years. Indicated by this market growth, the availability of position information will play an increasingly important role in current and future mobile information systems. Information about the position of a user or a mobile terminal (MT) can be exploited in a multiplitude of ways. Navigation services for both the consumer and professional market are probably the most well-known applications for positioning systems. Such services can be classified into the following categories:

1. Positioning: Determining solely the location of a person or object.
2. Tracking: Monitoring the movement of a person or object.
3. Navigation: Routing and guidance from an origin to a destination.

These categories are listed regarding increasing usage of auxiliary information and mutual dependency. As an example, tracking requires position determination of a target but usually also incorporates the movement history and a movement prediction of that target in order to achieve a more accurate estimation of...

Table of contents

• Cover
• Title Page
• Copyright
• About the Authors
• Preface
• Acknowledgements
• List of Abbreviations
• Chapter 1: Introduction
• Chapter 2: Positioning Principles
• Chapter 3: Measurements and Parameter Extraction
• Chapter 4: Position Estimation
• Chapter 5: Position Tracking
• Chapter 6: Scenarios and Models
• Chapter 7: Advanced Positioning Algorithms
• Chapter 8: Systems
• Chapter 9: Applications
• References
• Index
• End User License Agreement