This thought leadership report is a companion to our recently published: “DAS Rises to the Small Cell Challenge” (AN-1506) which examined the innovations in DAS (Distributed Antenna Systems) architectures as they evolve to compete with small cells in the medium to large building size verticals. This report builds on that and examines the impact on DAS and small cells architectures of the major trends in the industry.
Out of the many trends which are occurring in mobile telecoms today we chose to discuss the influence of 3GPP Progression, Virtualization, Traffic Steering and Load Balancing and Network Convergence on in-building wireless architectures. We believe that these trends will have a first-order influence on the architecture and performance of in-building wireless systems.
The progression of the 3GPP mobile standards will have a major influence on in-building wireless systems as the industry progresses to LTE, LTE-Advanced, and beyond. In-building wireless systems must evolve to accommodate LTE-A by ensuring there is enough bandwidth in the transport to carry the high data rates involved. This is particularly true for converged in-building wireless networks which will carry high data rate 802.11ac, Ethernet and other traffic in addition to the mobile traffic.
Since its inception DAS was a method of distributing cellular coverage but has now moved to enhancing capacity. Today’s systems are increasingly dynamic with various schemes for distributing capacity to where the demand is. This traffic steering and load balancing feature will become essential to lowering the CAPEX and OPEX of in-building installations by eliminating the need to provision for peak demand.
The concept of virtualization and CRAN are driving DAS and small cell architectures together to become a blended Distributed Radio System (DRS) where the baseband is centralized and the radio and antenna are distributed. Unlike DAS where only the antenna is distributed or small cells where the baseband, radio and antenna are all distributed. This evolution renders in-building DAS-style architectures economically viable in medium (100,000 sq. ft.) to large (500,000 sq. ft.) building sizes. Before DRS, DAS was only really economically viable in the large to very large (>500,000 sq. ft.) building sizes.