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How to Improve Forward Link Positioning for Cellular Networks? III. Hearability and Accuracy

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How to Improve Forward Link Positioning ... ? I. Introduction 1x HDP Enhancements Enhanced Location Based Services Support in cdma2000 Enhance Downlink Positioning in WiMAX/16m How Wide A Widband Channel Should Be? IEEE ICC 2008 Tutorial, Location Based Services for Mobiles Location Based Services for Mobiles: I. Introduction Hearability Issue Hearability of a forward-link positioning system usually is quantified by how many reference signals a terminal may utilize to make a positioning fix in a pre-defined positioning duration.  In theory, a terminal need measure parameters of only 4 different reference signals for a precise three-dimension fix.  However, more reference signals a terminal can use, more diversity benefits a terminal may use for a more accurate positioning fix. A hearability issue of a cellular positioning network generally is a dimension limitation issue.  It mostly is due to limitations of network geometry and network deployment.  In other words, it is

How to Improve Forward Link Positioning for Cellular Networks? II. Fundamentals

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How to Improve Forward Link Positioning ... ? I. Introduction 1x HDP Enhancements Enhanced Location Based Services Support in cdma2000 Enhance Downlink Positioning in WiMAX/16m How Wide A Widband Channel Should Be? IEEE ICC 2008 Tutorial, Location Based Services for Mobiles Location Based Services for Mobiles: I. Introduction In general,  how to improve forward link positioning in a cellular network is a mix of dimension limitation issues and  interference issues such as co-channel interferences.  It also relates to the well-known near-far issue.  In an actual development and deployment of a cellular network, both link budget and design target of the cellular network should be considered for improving forward link positioning.  Due to the complexity nature of this engineering issue, it is necessary to study it from various aspects and understand scalability of each involved engineering factor.  In the following, this topic is studied respectively from information theory, receiv

How to Improve Forward Link Positioning for Cellular Networks? I. Introduction

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How to Improve Forward Link Positioning ... ? III. Hearability and Accuracy 1x HDP Enhancements Enhanced Location Based Services Support in cdma2000 Enhance Downlink Positioning in WiMAX/16m How Wide A Widband Channel Should Be? IEEE ICC 2008 Tutorial, Location Based Services for Mobiles Location Based Services for Mobiles: I. Introduction There are many ways locating a mobile in a cellular network. The basic methods include dead reckon, proximity sensing, signal signature tracking, trilateration, multilateration, triangulation, etc. Some major approaches for cellular networks can be illustrated in Figure 1. Figure 1. Mobile Positioning Techniques, IEEE ICC 2008 "Location Based Services for Mobiles" Positioning performance is understood through quantifying the two parameters, hearability and accuracy. Hearability indicates how many hearable good references a terminal can track in a single snapshot. A typical number should be not less than 4. Accuracy is a well-