Cellphone users know that mobile coverage gets worse when they enter buildings. They nevertheless expect perfect usability from their phone. Shopping malls are a case in question, and the new and luxurious VillageMall in Rio de Janeiro required an efficient solution to such reception problems. About 8,000m² of heat-resistant glass covers the aisles and atriums of the building, and that absorbs radio frequencies just as well as steel and concrete. In order to achieve perfect cellphone communication within the mall, a distributed antenna system (DAS) fed by SPINNER's Mobile Network Combining System (MNCS) was installed.
For such a distributed antenna system the various network technologies of multiple operators have to be combined onto a single cable, which then gets distributed to the antennas. However, the combination of multiple frequencies and operators entails a certain risk. The more radio frequencies and operators are combined to one antenna signal, the higher the risk of dysfunction dominated by passive intermodulation (PIM) and isolation between the different signals. This negatively affects the overall radio quality and ultimately the user experience.
As a leading supplier of passive radio frequency (RF) technology, SPINNER offers best-in-class combining and distributing systems to support cost-efficient 2G, 3G, 4G/LTE and DAS (Distributed Antenna Systems) roll-outs. Brasilian Carrier Oi is hosting SPINNER's MNCS system, which initially combined Oi's and TIM's 2G, 3G and 4G base stations. In the subsequent steps Vivo and Claro were added, with each using another three radio technologies. The next step will involve Nextel being added to the same system.
"We've been impressed by the excellent quality of SPINNER's MNCS system. Low insertion loss and PIM as well as high isolation are critical for in-building systems and SPINNER's system has convinced us by delivering the best technical performance," said Gerson Monteiro, in-building systems engineer at Oi. "We also saw the flexibility of MNCS as advantage since we did not know in the beginning which radio technologies and operators would be going to join the system. The modularity of the MNCS system with its expansion possibilities is unique."
Anyone who visits a big mall like the VillageMall will tend to take perfect mobile reception for granted. Cellphone users do not see the tremendous behind-the-scene efforts required to achieve that goal. But thanks to the flexible and powerful MNCS from SPINNER, the effort involved for network carriers has now been reduced.