Advantages and Disadvantages Distributed Antenna System DAS

This page covers advantages and disadvantages of Distributed Antenna System (DAS). It mentions advantages of DAS (Distributed Antenna System) technology and disadvantages of Distributed Antenna System (DAS).

What is DAS or Distributed Antenna System?

As the name suggests DAS is a network of spatially separated antennas. They are connected to transport medium usually coaxial line or fiber optic line to provide wireless services within home or building premises. Distributed antenna system can be driven using direct connection with cellular base station or cellular tower or repeater.

Due to mobile data and cellular growth, it has become essential to install more number of small cells to counter rapid increase in number of mobile subscribers. This has opened door for distributed antenna system (DAS). In DAS, it is not required to install fresh cell phone tower rather antennas are mounted on existing cell phone towers. The figure depicts various cell phone tower types designed for specific applications. Refer tutorials on DAS basics and types >> and cell phone tower basics >>.

cell phone tower types used as DAS, Distributed Antenna System

In DAS technology, different antennas are mounted on single cell tower to relay frequencies in different bands of same or different technologies (GSM, CDMA, LTE etc). Antennas are installed by single telecom operator or by multiple operators on the cell tower.

DAS technology is required at following venues.
• Multi-tenant high rise building located in close vicinity.
• Corporate offices of Fortune 500 companies
• University campuses
• Manufacturing and production facilities
• Hospitals and Healthcare facilities
• Casinos
• Stadiums or sports venues
• Religious places such as Kaaba at Mecca
• Convention centers
• Hotels
• Federal or local Government facilities

Distributed Antenna System DAS

DAS are deployment of various antenna configurations. They are used to enhance or extend coverage of cellular signals inside and outside of structures. Hence DAS is used both as indoor antenna system as well as outdoor antenna system. Some of these system cover 2 or 3 floors and some cover many floors or areas of building or campus.

Advantages of Distributed Antenna System (DAS)

Following are the advantages of Distributed Antenna System (DAS):
➨They provide increase in capacity of cellular tower by having multiple antennas for single or multiple bands for multiple technologies (GSM, CDMA, LTE, LTE-Advanced etc).
➨In DAS technology, cell towers have provision to add antennas as per specific requirements in the future. Hence increase in bandwidth demand can be managed very easily.
➨It helps to provide internet connectivity in the single area by multiple telecom carriers.
➨It helps to overcome RF interference as same coverage is covered with lower transmit powers from various antennas.
➨It helps to provide greater customer satisfaction as there are no dropped calls or blocked calls. Moreover network access failures are less.
➨It helps to improve the speed of communication using MIMO/Beamforming techniques.

Disadvantages of Distributed Antenna System (DAS)

Following are the disadvantages of Distributed Antenna System (DAS):
➨DAS system requires multiple radio heads (or RRH >>) and connections of them with central Hub using fiber optic cables. Hence DAS system is very expensive.
➨DAS technology requires complex cable managament task in the backhaul part.
➨It is difficult to upgrade the system during modification process compare to small cell networks. This is due to the fact that OTA upgradation process is used in the small cell networks while DAS technology requires replacement of the systems (e.g. base stations and radio heads).

Antenna Related Links

Antenna tutorial    Types of antenna    TV Antenna    TV Antenna Booster    Satellite Dish Antenna    Mobile Antenna    Antenna Installation    Antenna Gain calculator    Antenna G/T Ratio calculator   Parabolic Dish Antenna   Antenna Near Field   Horn Antenna

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