ISE Magazine, January 2019

JANUARY 2018 WWW ISEMAG COM 93 C RAN The Challenges As with every innovation centralized RAN faces some considerable challenges in its deployment as a practical solution None are insurmountable but they can alter the calculus involved in deciding where and when to deploy C RAN architecture in a wireless network Fiber Optic Fronthaul Requirements Owing to the enormous amount of bandwidth required by current generation LTE networks to speak nothing of emerging 5G networks the fiber optic fronthaul infrastructure linking a sites radios to the remote BBU must meet high performance standards With LTE 10 Gbps speed is required along with extremely low latency time For many operators this means adding or upgrading existing fiber optic installations and investment in fiber infrastructure Reliable Baseband Interconnectivity Because C RAN concentrates BBU locations it can also create a point of vulnerability in the network In the event a BBU unit or multiple BBU units fails the C RAN hub itself must be equipped with a high speed low latency fiber optic switching infrastructure Without this foundation a failure in one unit could not be efficiently compensated by other units Its also important that the hubs switching network provide the flexibility and scalability to grow and adapt as the networks needs change over time Advanced Coordinated Multipoint CoMP Transmission and Reception All cellular networks face the challenge of interference that occurs in the overlapping areas of coverage between two sites In C RAN deployments its possible to pool signals from multiple antennas to create additional capacity where interference would otherwise occur This is done via a complex software algorithm Such an operation requires the extremely low latency times afforded by high speed fiber optic fronthaul infrastructure The real time cooperative processing involved requires virtualized BBUs interfaced with adequate speed and latency in order to process the channel information and end user data needed to make the solution work It also requires a correspondingly fast and low latency backhaul solution on the other side of the baseband processing Hub Locations Finding the best location to place a C RAN hub is a balancing act for network operators Placing it closer to the core enables them to consolidate a larger number of sites in one location but placing it closer to the edge could allow the operator to better utilize and repurpose existing facilities Often though the ideal location may be difficult or impossible to secure particularly in denser more urban environments In Building Wireless IBW Solution Centralized RAN has wireless applications beyond its obvious benefit to the macro network Wireless operators neutral hosts and even enterprise owners managers have access to C RAN based in building wireless IBW solutions As they do on the macro level C RAN IBW solutions make a strong case based on their improved economics reduced complexity and increased capacity C RAN is among the most exciting developments in the wireless industry over the past 20 years It represents a radical fundamental re imagining of the way wireless networks are designed and built a necessity considering how we are constantly re imagining what we expect our wireless networks to do Both in its centralized and Cloud based incarnations C RAN will answer operators calls for a more efficient more powerful network at a time when subscriber expectations far exceed their potential incremental revenue value In this way C RAN represents as fundamental a change to the business model of the wireless industry as it does to its architecture C RAN is indeed the network of the future and its already here n This article was adapted from a section of a CommScope e book Understanding the RF Path For more information about the e book please visit https www commscope com Resources eBooks Understanding the RF Path eBook utm_ medium social utm_ source commscope com blog utm_ campaign ebook rfpath Additional information and more about the e book can be found on the CommScope blog The Future of Cell Site Development by Mike Fabbri posted August 23 2018 https www commscope com Blog The Future of Cell Site Development utm_ source CommScope Blog utm_ campaign d29e8a5dcb RSS_ EMAIL_ CAMPAIGN utm_ medium email utm_ term 0_ 2f7cb19f4c d29e8a5dcb 189761169 Wes Oxlee is Director of Business Development at CommScope Connectivity Solutions business unit of CommScope Wes has 32 years of telecommunications industry experience with a primary focus on optical fiber external plant networks Previously Wes was with Telstra and NDC where he was the National Technical Specialist for fiber optics external For more information please email Wes Oxlee@ commscope com or visit https www commscope com