 |
| Remote Radio Unit |
A Remote Radio Unit (RRU) is a key component in wireless communication networks that provides flexibility and cost benefits. RRUs allow the separation of radio frequency components from the baseband unit, which controls network configurations and connections. This article explores the components, features, and advantages of using RRUs in wireless networks.
What are the Key Components of an RRU?
An RRU contains the radio frequency components needed to transmit and receive
signals. The main components included in most RRUs are:
- Power amplifier: Boosts the power of uplink signals received from user
devices before transmission to the baseband unit.
- Low-noise amplifier: Amplifies downlink signals from the baseband unit with
minimal noise added.
- Filters: Help isolate and separate uplink and downlink frequency bands to
prevent interference.
- Duplexers: Combine or separate transmit and receive signals on a single
antenna using frequency division duplexing.
- Antennas: Used for transmitting and receiving radio signals to and from user
equipment in the coverage area.
Remote
Radio Unit also have an interface to connect to the baseband unit using
Common Public Radio Interface (CPRI) or Open Base Station Architecture
Initiative (OBSAI) protocols. This allows remote control and management from a
centralized location.
Baseband Unit Functions
The baseband unit controls multiple Remote Radio Unit and performs crucial
network functions like:
- Resource allocation: Assigning timeslots and frequencies for uplink/downlink
transmissions.
- Power control: Adjusting transmit power levels of RRUs and user devices.
- Mobility management: Handling handovers as users move between coverage areas.
- Admission control: Determining if a network can accept additional user connections.
- OAM&P: Performing operations, administration, maintenance, and
provisioning tasks.
- Protocol termination: Managing communication protocols like 3G UMTS, 4G LTE,
etc.
The baseband unit provides intelligence, while RRUs handle the actual radio
interfaces with user equipment in the field. This separation of
responsibilities streamlines operations.
Key Benefits of Using Remote Radio Unit Architecture
There are several technical and operational advantages of deploying RRUs
instead of traditional combined radios:
Flexibility
RRUs allow radio resources to be dynamically reconfigured from the baseband
unit by adjusting settings like transmit power and antennas used. This makes
them highly flexible for fluctuating traffic demands.
Simplified Maintenance
Individual RRU components like power amplifiers and antennas can be easily
replaced or upgraded without affecting the entire radio system. Periodic
on-site maintenance is minimized.
Lower TCO
RRU architecture significantly reduces total cost of ownership over long-term
network operation through simplified logistics, replacement of components, and
energy efficiency gains.
Capacity Expansion
Adding additional RRUs to an existing baseband unit's coverage provides a
simple way to boost capacity without deploying whole new base stations.
Future Proofing
The modular RRU approach future-proofs network investments as radio
technologies evolve over years. RRUs can adapt to new standards like 5G through
software upgrades managed remotely.
RRUs have emerged as an important technology enabler, giving
operators greater control, flexibility, and economics compared to combined
radio solutions. Their use will continue expanding in cellular and private
network deployments globally.
This article provided an overview of remote radio units as a key partitioning
technology in modern wireless infrastructure. RRUs separate the radio frequency
components from the baseband unit's intelligence and network control functions.
By doing so, they deliver significant technical, operational and economic
advantages to network operators. The modular RRU architecture supports seamless
capacity increases and future-proofs investments as wireless technologies
advance. RRU adoption is poised to grow further with the rollout of 5G networks
worldwide.
0 Comments