3G Indoor Coverage Planning

Course Overview

Customers of mobile networks expect to have reliable 2G coverage wherever they are, and they will expect the same and more for 3G. There are new considerations for experienced 2G planners when adding 3G to existing indoor systems or designing new 3G solutions. This course focuses on the differences between GSM and UMTS indoor coverage planning. Students will learn how 3G traffic characteristics differ from those of 2G in the indoor environment and how channels are configured on UMTS cells.

There is a brief review of indoor propagation leading to a discussion of Code Division Multiple Access (CDMA) characteristics in the indoor environment. Both small and large scale Distributed Antenna System (DAS) architectures suitable for UMTS are discussed, with a focus on radio over fibre systems. Students will also learn how to determine the most appropriate and cost effective coverage strategy in a range of scenarios including offices, retail outlets, tunnels and sports stadiums.

Audience

Experienced GSM Indoor planning engineers moving into UMTS indoor coverage, as well as those working in planning-related areas or needing to understand UMTS planning considerations.

Skills Gained

On completion of this course the student will be able to:

• identify effective strategies and general procedures that enhance the indoor planning process
• identify typical 3G offered traffic levels, blocking limits and characteristics for a range of indoor coverage scenarios
• describe how UMTS cells are dimensioned for circuit-switched and packet-switched traffic
• outline how packet data capacity can be provided in 3G cells with WCDMA and HSPA
• review key propagation effects in buildings, tunnels and sports stadiums and identify where waveguide effects may occur
• explain how CDMA characteristics impact the coverage performance of UMTS in the indoor environment
• explain how repeaters can be used to provide indoor coverage and capacity in UMTS
• identify indoor coverage scenarios where it would be better to use a dedicated picocell than a repeater
• review the design of passive and active distributed antenna systems and list factors that determine radiated power and noise contribution
• explain the design of optical fibre for distributed antenna systems and identify advantages in their use
• discuss the relative merits of shared indoor systems in respect of UMTS
• perform link budget and balancing calculations on typical indoor coverage systems
• describe how UMTS indoor cells can be integrated into the wider coverage network

Prerequisites

Attendees should already have knowledge and experience of 2G indoor coverage planning.

Course Outline

Dimensioning for Traffic

• Shared solutions and general benefits
• Sharing for UMTS systems
• Typical voice traffic levels
• Traffic for indoor users
• Target blocking levels
• Office and corporate traffic dimensioning
• Scenario 1 - general office coverage
• Scenario 2 - corporate subscription in office
• Scenario 3 - full corporate solution
• Dimensioning a UMTS Node B
• UMTS cells and channel elements
• UMTS power amplifier limits
• UMTS data requirements
• Dimensioning for shopping centres
• Exercise 3 - CS traffic in the Trafford Centre
• Packet Switched (PS) traffic
• PS service characteristics
• Packet data modelling
• HSDPA capacity utilisation

Indoor Propagation

• Time dispersion
• Inter Symbol Interference (ISI)
• Delay spread for UMTS
• Waveguide effects in buildings
• Waveguides and cellular systems
• Indoor propagation models
• General model types
• Statistical models
• Basic power law model and example
• A site-specific model
• Modified Keenan-Motley model and example
• Exercise 1 - using a statistical model
• Deterministic models
• Ray tracing

Achieving Coverage in the Indoor Environment

• The indoor coverage paradox
• General requirements
• Initial coverage survey
• Measurement using a test transmitter
• Indoor antenna locations
• Indoor-outdoor demarcation
• Maintaining even coverage
• Consideration for service types
• Noise rise and load factor for UMTS
• Link budgets
• Load factor
• Tunnel propagation and tunnel characteristics
• Creating cells
• Stadium coverage requirements
• Antenna location possibilities
• Radiation limits and safety
• ICNIRP guidelines
• Considerations for indoor antennas
• Example calculations for UMTS and GSM
• Multi-operator/multi-RAT system example

Sources of RF for Indoor Coverage

• Indoor coverage methods
• The four main options
• Antenna isolation and gain setting
• UMTS Node B desensitization
• Exercise 1 - repeater gain and isolation
• Customer repeater solutions
• Donor antenna alignment for UMTS
• Repeaters to add capacity in UMTS
• Dedicated pico cell
• Pico cell implementation options
• Pico cell equipment
• System type selection
• Generic radio access for indoor coverage
• The femtocell

Copper and Fibre DAS

• Antennas for indoor systems
• Leaky feeders
• Distributed antennas using coaxial feeder
• Passive distribution
• Measured signal levels for UMTS
• Combined passive/active coax DAS
• Fibre optic distribution systems
• Advantages of using fibre optic cable
• Light spectrum for fibre
• Optical distribution
• Multi mode and single mode (monomode) fibres
• Fibre system architecture
• Indoor diversity designs
• Mobile antenna patterns
• Receive space diversity
• Transmit time diversity

Integrating Indoor Cells

• Indoor cell reselection
• UMTS cell reselection
• Reselection with Hierarchical Cell Structures (HCS)
• Picocell handovers
• Handovers between indoor and outdoor cells
• UMTS handover measurement types
• UMTS event triggers
• Event type 1 - example

Indoor Coverage Planning Exercise

• Building details
• Performance requirement
• Equipment availability

Benefits of the course

In addition to gaining a good understanding of 3G indoor coverage planning, this course will enable the student to deliver operational improvements and generate cost savings or reduce project timelines by:

• improving network design, planning, operations and maintenance
• avoiding the laborious search through specifications, standards and white papers, while benefiting from a practical analysis and
• interpretation of such documentation by experienced engineers
• knowing better where to look to accelerate research and fact finding and facilitate earlier project completion
• improving the equipment procurement process by better analysis and challenge of technical specifications and supplier responses, thus
• giving greater certainty to on-target performance and value-for-money purchasing
• shortening the learning curve and speeding productive inputs from new team members and freeing more experienced employees' time
• evaluating better a system's capabilities through improved knowledge, leading to superior operations and maintenance performance
• providing greater confidence in the sale of equipment by anticipating customers' technical requirements and being able to promote relevant
• superior equipment performance

Follow On Courses

Students may wish to extend their planning skills into optimization by attending the Introduction to GSM Optimization or Introduction to UMTS Optimization courses. Others may wish to increase their knowledge of radio access technologies with the HSPA Principles and Application or WiMAX Engineering Overview courses. SDH Principles, ATM Principles, TCP/IP Protocol Suite, and MPLS Overview may interest those involved with terrestrial communications links for radio sites.

3G Indoor Coverage Planning / MB2701