In-Building COVERAGE SolutionS

Active DAS concept distributes RF signal from BTS or Node-B to antennas inside a building by making use of fiber optics and active modules that converts the optical signals back into RF signals after long distribution runs

There are 2 concepts for Active DAS which are Full Active DAS and Hybrid Active DAS:

• Full Active DAS concept distributes RF signals from BTS, Node-B or eNode-B to the active antennas through an active unit which consists of a Main Unit (MU), Expansion Unit (EU) and Low Power Remote Unit (LPRU). 

  • The Low Power Remote Unit (LPRU) demodulates the signal to RF Signals and amplifies the signal before transmitting it through its internal Active Antenna. 

• Hybrid Active DAS concept distributes RF signals from BTS, Node-B or eNode-B to the passive antennas through an active unit which consists of a Main Unit (MU) and High Power Remote Unit (HPRU). 

  • The High Power Remote Unit (HPRU) demodulates the signal to RF Signals and amplifies the signal before transmitting it into the Passive DAS where the antennas are connected using coaxial cables and passive components. 

Passive DAS concept distributes RF signals from BTS or Node-B to antennas inside a building using coaxial cable and passive components such as filters, combiners, splitters, couplers

 There are 2 deployment scenarios for Passive DAS which are Centralized RRU and Distributed RRU:

• Centralized Remote Radio Unit (RRU) concept refers to the placement of all sector RRU, whereby the RRU is located together with the BTS, Node-B or eNode-B in the Equipment Room or the Main Distribution Frame (MDF) Room.

  • Centralized concepts are used if coverage areas are not too far away from the MDF Room where the RRU's are located, thus having minimal RF losses from RRU to Antenna via coaxial cables.

• Distributed Remote Radio Unit (RRU) concept refers to the placement of all sector RRU, whereby the RRU is located in remote locations instead of being placed together with the BTS, Node-B or eNode-B in the Equipment / MDF Room.

• The RRUs will be placed nearer to the intended sector coverage area using optical cables which connects it to the BTS thereby eliminating coaxial cable losses from the main trunk.