What is RRU, BBU and Antenna?

Refreshing some basic concepts.

  • BBU (Baseband Unit): manages the whole base station, including operating maintenance as will as signal processing.

  • RRU (Remote Radio Unit): interface with Antenna in one side and with BBU in the another side.

    • Converts the RF signal into data signal and the vice versa.
    • Filtering and amplification of RF signal.
    • Decides the coverage of the power capability.
  • Antenna: interfaces with cell phone wirelessly and transmits/receivers RF signals

    • Decides that shape of the coverage

1 Like
  • Important Information about Radio Unit (RRU)

    • Radio Remote Unit (RRU) is the distributed and integrated frequency unit that connects to an operators network with the User Equipment’s (UE’s) like Cell Phone and mobile devices.

    • The logical term “distributed and integrated” is because traditionally the radio architecture for cellular system is based on a single-standalone system (Base Stations) usually installed indoor but now, the cellular architecture is divided.

    • BTS (Base Transceiver Station) is the integration of various radio unit like BBU and RRU. Despite installing only in indoor , radio units are now installed in the tower below the Antenna.

    • The RRU is connected to the base station via the fiber optic link which is bi-directional link. The optical interface link is also known as CPRI(Common Public Radio Interface). CPRI is a interface protocol developed by combination of major telecom equipment’s manufacturing company.

    • The RRU helps to reduce the coaxial feed line losses, increase system efficiency and provide high level of flexibility in cellular site construction. Undoubtedly, this helps in upgrading to new equipment’s and devices more easily.

  • RRU Functions :

    • Acts as a transceiver: transmit and receive the user signals to the base station and vice-versa.
    • Provides back to back support and connectivity between user equipment’s like power, delay,etc.
    • Control and process the EM signals received from the Antenna via Jumper(Hollow Guide).
    • Provide interface between two physical link: Optical and EM(Electromagnetic).
    • Provide controlling support of the Auxiliary equipment’s like RCU (Remote Control Unit) for electrical tilt adjustment generally known as RET (Remote Electrical Tilt).
    • Generate and sends the different signals like VSWR, RET, ACT,etc.
  • RRU Hardware Description

    • CPRI Port

      • Here are 2 ports generally named as CPRI0 and CPRI1. However there may be 1’s in some model. The name at suffix may vary. Its function is to connect to BBU.
    • RF Port

      • We say it as a Jumper port. The number of jumper port may vary with model and company’s architecture. At least there is * jumper port, one of which is for Tx and another for Tx/Rx. The RF port is connected to the Antenna via Jumper Cable.
    • RET Port

    • There is at least one RET port for connection to RCU. The connector is mostly DB9 in Huawei and may vary with other company’s. RCU is connected to the Antenna. RET cable connects the RCU and RRU.

    • Power Supply Port

      • There is one port for powering the RRU. Mostly blue and black. Blue is for negative (-) and black is for zero(0). Generally all RRU operates in -48V.
    • Ground Port

      • There is two OT port for the grounding. The ground cable: mostly copper wire, one end is connected to RRU and another end into Bus Bar near by RRU. Thus it provides the surge and high voltage protection of RRU and thus keeping safe from natural weather and climates.

5G Baseband Units (BBUs)

5G Baseband Units (BBUs) are essential components of modern wireless communication networks, particularly in 5G technology. They manage and process the digital signal to ensure seamless connectivity and high-speed data transmission.

  1. :brain: Brain of the Network: BBUs act as the brain :brain: of a 5G network. They process and control the digital data flow :globe_with_meridians: between the radio frequency (RF) side (Radio Unit, RU) and the network core side (Central Unit, CU), making sure the data is transmitted efficiently and accurately.

  2. :control_knobs: Modulation & Demodulation: BBUs handle the modulation :signal_strength: and demodulation of signals. They convert the digital data bits (0s and 1s) into waveforms :ocean: suitable for wireless transmission and vice versa. This process ensures that the data can be transmitted over the airwaves and received accurately by the user devices :iphone:.

  3. :tokyo_tower: Cell Tower Management: BBUs are installed at cell towers :tokyo_tower: to manage the radio resources within a specific geographical area, known as a cell. They help allocate and optimize radio resources :satellite: for each user, ensuring a smooth and reliable connection for everyone in the area.

    Example: When you make a video call :video_camera: using your 5G smartphone :iphone:, the BBU at your nearest cell tower :tokyo_tower: modulates your voice and video data, allocating the necessary radio resources to transmit the data to your friend’s phone :calling:. The BBU at your friend’s nearest cell tower demodulates the data and ensures it’s delivered to their phone.

  4. :arrows_counterclockwise: Handover Management: As users move from one cell to another, BBUs manage the handover process :handshake:, seamlessly transferring the connection from one cell tower to another. This ensures continuous and uninterrupted connectivity :globe_with_meridians: as you travel :walking_woman::red_car::airplane:.

  5. :chart_with_upwards_trend: Scalability & Flexibility: Modern 5G BBUs are designed to be scalable :chart_with_upwards_trend: and flexible, meaning they can adapt to varying network demands and support new features as technology evolves. This enables network operators to efficiently manage their resources and provide improved performance :rocket: and coverage :globe_with_meridians:.

In summary, 5G Baseband Units (BBUs) play a crucial role in managing and controlling wireless networks, ensuring seamless connectivity, efficient resource allocation, and adaptability to support the ever-growing demands of 5G technology. :star2::signal_strength::iphone:

LinkedIn: :point_down:

1 Like