Wireless Infrastructure Quiz

Philippine Electronics Code (Book 4) - Distributed Antenna System (DAS)

• The Distributed Antenna System (DAS) is an in-building solution comprised of multiple pico cells to provide wireless coverage using 2G, 3G, 4G, and potentially 5G technology.
• A specific number of antennas forms a single sector strategically installed within a building or compound to achieve a unified objective.
• In in-building solutions, a sector serves a grouping of dedicated antennas within the structure, methodically arranged.

Table of Contents

• Distributed Antenna System (DAS)
• RF Material Specifications
• RF Material Design Criteria
• DAS Installation
• DAS Technical Standards
• DAS Physical & Logical Installation & Quality Acceptance
• General Safety Precautions Practices

Chapter 1: The Distributed Antenna System

• The Distributed Antenna System (DAS) is an in-building solution for wireless coverage and services employing 2G, 3G, 4G, and upcoming 5G technologies.
• A predetermined number of antennas create a single sector, strategically placed within a building or compound.
• These sectors function as one entity, delivering targeted wireless services.
• In in-building scenarios, a single sector manages a cluster of strategically positioned antennas within the structure.

Chapter 1: Sector

• A sector is a designated division within a Base Transceiver Station (BTS) containing dedicated resources for wireless service delivery to a specific number of users.
• Three sectors collectively compose a single BTS.
• Sector configuration is adjustable based on building service/capacity requirements to maximize user benefit.
• Wi-Fi and Trunk radio communication systems are handled independently from the DAS.

Chapter 1: Schematic Diagram of a Distributed Antenna System

• Visual representation of a DAS, showcasing the equipment room, Base Transceiver Station (BTS), jumper cable, and distributed antenna system.
• Components like technology 1, technology 2, technology 3, and combiners are indicated.
• Illustrates the interconnections between various components of a DAS

Chapter 1: Classes of Distributed Antenna Systems

• Individual DAS System (IDAS): A DAS system exclusively serving a single wireless service provider or operator.
• Common DAS System (CDAS): A DAS system jointly used by multiple wireless service providers or operators. Each antenna within a common DAS simultaneously carries signals from multiple service providers who have agreed on shared use.

Chapter 2: The RF Antenna

• RF antennas operate based on the fundamental principles of electromagnetism. When an RF signal is applied to an antenna, an electromagnetic field is generated, radiating energy into space.
• Includes classifications of antennas like Pico Omni-Directional antennas and Directional/Panel antennas.
• Contains general technical specifications for omni-directional and directional/panel antennas detailed in tabular formats (frequency, gain, VSWR, impedance, polarization).

Chapter 2: RF Material Specifications

• Overview of RF cables (feeder/coaxial cable, fiber optics cable, jumper cables, radiating/leaky cables).
• The presentation identifies two major feeder cable sizes (7 and 8).
• Detailed technical specifications for the 1/8 feeder cable, including different components (e.g., inner conductor, dielectric, outer conductor).
• Specifications are given in tabular formats.

Chapter 2: Combiners, Couplers, Splitters

• Discusses the functions and types of combiners, couplers, and splitters in various forms—diplexer, triplexer.
• Explains what directional couplers are and how they distribute signal power.
• Covers hybrid couplers, which split input power equally among outputs.
• Includes Dummy Load component in the system.

Chapter 2: RF Equipment Type Approvals

• This outlines the international standards for the materials used in RF installations based on IFC and IEEE standards.
• Discusses specific tests like Mechanical Tests, Thermal Expansion and Temperature Tests, Corrosion Tests, Weather Protection, and Electromagnetic Discharge to ensure component stability and performance over time and under various environmental conditions.

Chapter 3: The RF DAS Design Criteria

• Presents considerations for wireless technology deployment in designing in-building solutions.
• Considers target coverage objectives, the number of subscribers, and technology deployment.
• Key Performance Indicators (KPIs) which include: CPICH, RSCP, Ec/lo, RSRP, RSRQ, SINR and PIM are identified for quality design.
• Table presentation showing the required minimum values for each indicator and technology.
• Capacity design considerations are described considering foot traffic and seating capacity.
• The importance of Grade of Service (GoS) - the probability of call blocking or delays over a given interval -- when calculating capacity in the building.

Chapter 3: Target Coverage Objective

• Establishes a categorization of target areas based on their nature (e.g., public access areas versus incidental areas).
• Presents classifications of buildings by purpose (e.g., shopping malls, hospitals etc.).
• Includes building types classification based on vertical rise (e.g., low rise versus high rise) and horizontal configuration (e.g., low rise expanded or arenas).
• Defines various design requirements given by building types.

Chapter 3: Types of DAS Design

• Describes Passive DAS Solutions - those using only passive components with no line amplifiers.
• Describes Pure Active DAS Solutions - those where every antenna features a dedicated remote radio unit.
• Introduces Hybrid Active – Passive DAS Solutions - where the entire radio unit is situated close to the first passive component.

Chapter 4: The DAS Installation

• Indoor Antenna Installation Overview - describing installation techniques for various antenna types including omni-directional and panel antennas, placement and aesthetics.
• Detailed information on installation procedures.
• Overview of component installations (specific components and their installation points).
• Installation steps for wall/roof feed-thru plates, including marking points and securement.
• Detailed information regarding RRU (Remote Radio Unit) installation: placement methods on metal poles, walls, and U-steel. Details on cable installation at the riser.

Chapter 5: The DAS Technical Standards

• Equipment Room Standards—specifying dimensions, location, requirements, and auxiliary components (e.g., grounding).
• Electrical Standards—outlining AC power supply and surge protection requirements (Transient Voltage Suppressors and AC Power Distribution Block and their function). Describing the grounding system used for the DAS.
• Transport Standards— detailing microwave, fiber optic, and IP RAN installation guidelines (including cable types, components that are used, and installation procedures).

Chapter 6: The DAS Physical and Logical Installations Quality and Acceptance

• Quality Assurance (QA) process - describes a process that ensures a product, service, and process meets quality standards.
• DAS installation is secure via methods like visual inspections and checklist adherence.
• DAS acceptance testing involves verifying signal quality with measurements and acceptable coverage levels.
• Handover — describes the smooth signal transition between neighboring antennas or different zones, considering operator specifications and constraints.
• Spillpage and Overshoot — defines and describes undesirable signal characteristics like spillage and overshoots that needs to be minimized.
• General Safety Precautions Practices covering topics like personal equipment checks, working procedures, ensuring de-energization, and working area requirements.