Active antenna systems are the next step in the evolution of radio networks, reducing capital and running costs significantly, while also providing even greater capacity and coverage. Nokia Siemens Networks is leading the way with its Flexi Multiradio Active Antenna System, which integrates the base station’s radio frequency (RF) elements into the antenna.
A similar size to conventional passive antennas with the active array included, Nokia Siemens Networks Flexi Multiradio Active Antenna System offers much greater performance and brings major benefits to operators.

Benefits of Flexi Multiradio Active Antenna System
1. Lower overall site costs
- Integrated antenna array eliminates coaxial cabling, feeders and connectors to reduce RF power losses. This raises overall energy efficiency to reduce electricity costs and carbon emissions for a much greener site.
- The active antenna system is easy to install and has fewer components by eliminating the need for Mast Head Amplifier (MHA) and Remote Electrical Tilt (RET) equipment, reducing installation and site costs.
- More compact installation than traditional passive antenna systems with adjacent RF modules/RRHs, helping to reduce site rental costs.
- The active antenna system has inherent redundancy because the failure of one or more TRXs will not disrupt services. This reduces operational costs by enabling a more flexible maintenance program.
2. Higher capacity and coverage
- Advanced features like vertical beamforming, 2 x 2 Multiple Input Multiple Output (MIMO) and independent Tx and Rx electrical tilting per frequency or radio access technology improve coverage and capacity.
- Vertical beamforming provides up to 65% capacity gain, in addition to standard 3-sector feederless site.
- Future active antenna developments are expected to support multiple columns and horizontal beamforming to further enhance capacity.
3. Protects existing site investments
- Supports GSM/EDGE, WCDMA/HSPA, LTE and LTE-Advanced to enable existing base station sites to be upgraded smoothly and quickly.
- Combines active and passive elements to support traditional base stations on additional frequency bands, eliminating the need to install additional antenna elements when deploying new frequency bands.
Nokia Siemens Networks Flexi Multiradio Active Antenna System offers
1. CAPEX/OPEX savings from integrated solution:
- Easy installation
- Less wind load
- Lower site rental cost
- No MHA (Mast Head Amplifier)
- No separate RET (Remote Electrical Tilt) equipment
2. Energy/OPEX savings:
- Radio frequency losses minimized
- No feeders/jumpers/connectors
3. Flexible maintenance from inherent redundancy
4. Supports active/passive antenna combinations, to enable the use of existing feeders on the passive array