Book contents
- Frontmatter
- Dedication
- Contents
- Preface
- Acknowledgements
- List of abbreviations
- 1 Introduction
- 2 WCDMA in a nutshell
- 3 Spreading codes and modulation
- 4 Physical layer
- 5 RF aspects
- 6 Chip rate processing functions
- 7 Symbol rate processing functions
- 8 Layer 2 - medium access control (MAC)
- 9 Layer 2 - RLC
- 10 PDCP and BMC protocols
- 11 Layer 3 - RRC
- 12 Measurements
- 13 NAS
- 14 Idle mode functions
- Appendix
- References
- Index
12 - Measurements
Published online by Cambridge University Press: 05 October 2013
- Frontmatter
- Dedication
- Contents
- Preface
- Acknowledgements
- List of abbreviations
- 1 Introduction
- 2 WCDMA in a nutshell
- 3 Spreading codes and modulation
- 4 Physical layer
- 5 RF aspects
- 6 Chip rate processing functions
- 7 Symbol rate processing functions
- 8 Layer 2 - medium access control (MAC)
- 9 Layer 2 - RLC
- 10 PDCP and BMC protocols
- 11 Layer 3 - RRC
- 12 Measurements
- 13 NAS
- 14 Idle mode functions
- Appendix
- References
- Index
Summary
Introduction
The UTRAN contains many terminals spread across the coverage area. WCDMA is an RAT that is dependent upon the interference levels within the network. To maintain an acceptable operating point, therefore, the UTRAN needs to have precise knowledge of the system status at any given point in time. To provide this understanding, measurements are made throughout the radio network, and the measurement information delivered to the UTRAN for processing.
The measurements themselves are made by the UE and the UTRAN. The types of measurements made by the UE range from cell signal quality measurements to traffic volume measurements. In general, the type of measurement that a specific UE makes at a given point in time is defined by the UTRAN.
One overriding concept that we meet through the course of this chapter is the relationship between the RRC states and the cell signal measurements that are made by the UE. We will see that there is a distinct difference between the measurement activities of a UE in the CELL_DCH state compared with its activities in all other states (CELL_FACH, CELL_PCH, URA_PCH and idle mode). In CELL_DCH the UE makes measurements and reports them to the UTRAN for action by the UTRAN, in all other states the measurements are not reported to the UTRAN and the UE takes action based on the measurements.
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- Information
- WCDMA Design Handbook , pp. 395 - 436Publisher: Cambridge University PressPrint publication year: 2005