Brian Collins, Chair, AISG
Steven Gallagher, Solution Architect, Alpha Wireless
Steve Giles, Head of RAN design, MBNL
David Barker, CTO, Quintel Technology
Antenna designs have evolved rapidly to provide increased operating bandwidths in response to the ever increasing number of frequency bands assigned for mobile network use. New challenges are being created by the introduction of new frequencies between the existing band blocks. The number of functional arrays that can be packed into a single sector antenna continues to increase, with 10, 12 and even more RF ports on the horizon.
The densification of networks to support solid LTE coverage and the use of higher frequencies that require more, smaller, cells can create visual clutter and potential conflict with city planning authorities. The situation is being addressed by the increased sharing of sites between networks, and the use of compact tri-sector antennas that use a single cylindrical radome. Bespoke disguises are effective but expensive. Small street-works sites are in widespread use in some countries, merging with the existing cityscape of street lights and other street furniture, and easily connected to existing street level fiber.
Active antennas are widely seen as a technology needed to support high-order MIMO operation for later 4G and 5G services. The use of ‘massive’ MIMO is seen as the future for the higher frequency bands, but issues of physical size, potentially high peak eirps and integration into multi-band base stations, make it difficult to predict the extent to which they will be adopted.