Indoor Radio Planning: A Practical Guide for GSM, DCS, UMTS, HSPA and LTE, Second Edition

4.2 Passive Components

Before you start exploring the design of passive distributed antenna systems, you need to have a good understanding of the function and usage of the most common type of passive components used when designing indoor passive distributed antenna systems.

4.2.1 General

Inside buildings you must fulfill the internal guidelines and codex that apply for the specific building. In general you will be required to use fire-retardant CFC-free cables and components.

Be very aware of how to minimize any PIM (passive intermodulation) problems. Also be sure that the components used fulfill the required specification, especially when designing high-power passive distributed antenna systems. The effect of combining many high-power carriers on the same passive distributed antenna system using high-power base stations will produce a high-power density in the splitters and components close to the base stations. Use only quality passive components that can meet the PIM and power requirements, 130 dBc or better specified components (see Section 5.7.4).

4.2.2 Coax Cable

Obviously coax cable is widely used in all types of distributed antenna systems, especially in passive systems. Therefore it is important to get the basis right with regards to cable types, and losses. Table 4.1 shows the typical losses for the commonly used types of passive coaxial cables. For accurate data refer to the specific datasheet for the specific cable from the supplier you use. Often there will be a distance ...