A guide to choosing Base Station Antennas
Challenges of 5G roll out
Today’s mobile applications require a high network availability as well as high traffic throughput. With the challenging landscape of the modern cities (tall buildings, city squares, high population density, etc.), efficient network coverage becomes critical for the delivery of a good quality of service to the end user. Moreover, in dense urban areas, the population density increases the need for high-capacity networks absorbing the increased traffic demand.
In addition to the demands we have spoken previously about the site footprint challenges that operators are facing. It could be that increased loading results in the need for early reinforcement of the tower due to increased windload, or the increase of fees paid by the mobile operators to the tower companies. However, in all cases the result is the same – increased site TCO. The combination of demands and restrictions puts operators in a challenging situation making selecting the right equipment imperative.
Pushing passive to its potential
5G sites are expensive in terms of CAPEX and OPEX. That’s why the legacy, less-expensive technologies will continue to be a big part of any cellular network. This leads to the imminent need for highly efficient passive base station antennas supporting various frequency bands, with minimal footprint and windload. It is vital legacy technology does not mean legacy equipment. It must continue to evolve and address site restriction challenges and integration with new technologies to benefit the wider ecosystem.
The ‘form factor’ factor
Form factor is a big part of continuing evolution. A slimmer form factor can allow more antennas on a site and reduce windloading which puts particular strain on existing site. Equipment working harder, incorporating more technologies, in the same space is a must for operators as 5G roll outs continue. Let’s look particularly at how we have tackled this at RFS.
RFS compact antennas have an innovative radome design which reduces windloading by up to 25% to help postpone costly structural upgrades to towers and lower total cost of ownership (TCO). Combined with a slim design to maximize space and constant innovation to improve performance, we have worked to tackle head on the issues that continue to plague operators.
Selection guide
Multiple solutions allow operators to ensure the BSA solution they select best addresses the problems they face at that site. The RFS Compact platform is the basis of a wide portfolio of BSA systems covering various antenna technologies to support a huge range of use cases. Below is a guide to the four main antenna families and the use cases they are best suited to.
| Multi-band Passive | Hybrid FDD/TDD | Hybrid Multibeam | Small size | |
| Overview | Supports configurations from 2 ports up to 18+ ports. They are able to support a wide frequency spectrum and offer various configurations of RF ports and frequencies | Offers a low power and low-cost way of rolling out basic 5G NR. 5G NR with TDD 8T8R beamforming can be introduced in a single antenna that also supports legacy technologies (e.g. 2G/3G/4G.) |
Passive antennas with a variety of beam configurations. Allows density to be increased in specific areas or coverage extended with improved signal at radio cell edge. |
Small form factor antennas with a height below 90cm. Can be single band or multiband. Offer configurations from 2 ports up to 16+ RF ports. They can be also panel or omnidirectional antennas. |
| Use Case | Supporting legacy technologies (e.g. 2G/3G/4G). It combines all legacy technologies in a single antenna and maximize free space on the tower to introduce 5G mMIMO active antennas. | To deliver standard 5G where there are other site constraints preventing the use of 5G mMIMO active antennas. This can be used in low density sites, or if there is a power consumption restriction. | For outdoor areas with high population density or high footfall (e.g. a stadium). This type of antennas can also be used as a long range radio cell to improve the signal strength at site borders. | Suitable for areas with high-rise buildings and high population density. Where the cellular macro layer is not sufficient to deliver the required high-capacity. Small size antennas can fill the coverage and capacity gaps. |
Conclusion
Sadly, there isn’t a silver bullet when it comes to solving 5G roll out challenges. There isn’t a one size fits all or a single ‘best’ base station option but instead operators need to be able to choose from multiple options each catering to specific use cases. The selection of the equipment is a balancing act of form and function and having a partner with a broad and comprehensive portfolio gives the tools to build the best infrastructure configuration depending on the environment.
