HETEROGENEOUS NETWORKS VIKAS REDDY BEERAVALLY Radio Network Evolution to heterogeneous Todays Networks Single Standard Radio Single Layer Network Fragmented homogenous deployment scenarios •Macro outdoor •DAS indoor, some outdoor •Femto indoor •WiFi indoor, some outdoor 2015 Heterogeneous Networks Multi Standard Radio Multi Layer Network Heterogeneous deployment scenarios Operator Deployed (Macro, Micro, Pico, DAS, WiFi, Femto) Neutral Host Deployed (DAS, WiFi) User Deployed (Femto, Wifi) MBB Heterogeneous Networks MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Improve existing macro cell sites • By enhancing macro cells with more spectrum, advanced antennas, increased order of diversity on the receiver and/or the transmitter, and greater baseband processing capacity within and between nodes. • Continued evolution of HSPA and LTE technology will drive macro network efficiency through specialized features, such as higher-order modulation, higher sectorization, multi-carrier and multi-antenna solutions, as well as spectrum reframing using hybrid radio solutions. • Increasing capacity and data rates in this way eliminates the need for new sites MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Densify the macro network The capacity and data rates achieved by enhancing the macro network alone will eventually prove insufficient to meet demand. The targeted addition of strategically located small cells can improve capacity. This approach keeps the total number of sites relatively low, while network performance becomes less sensitive to traffic location. A simple way to density a network could be a cell-split, which enables a site to transition from a three-sector site to a six-sector site. these strategic cells could use macro equipment or even micro equipment MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Add small cells Complement macro cells with small cells and dedicated indoor solutions based on the 3gPP standard. this approach can include the use of micro cells, pico cells or low-power remote radio units (RRUs), as well asWi-Fi. It delivers high per-user capacity and rate coverage in areas covered by the small cells, with the potential to improve performance in the macro network by offloading traffic generated in hotspots. The degree of integration that can be achieved throughout the heterogeneous networks will determine the overall network performance MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Super Macro Micro, Pico Relays MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Cell Coordination In a heterogeneous network, the coordination between macro cells and small cells has a positive impact on the performance of the radio network and consequently on the overall user experience. Coordinated embedded small cells improve performance through frequency reuse, increasing both network data capacity and throughput without the need to split the available spectrum. The highest coordination gain is achieved when using a dedicated high-bandwidth, low-latency link among several radios provided by the same baseband MAKING RIGHT HETEROGENEOUS NETWORK CHOICES MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Coordination between the macro and small cells enables close cooperation on cell selection especially in areas where the macro signal is strongest in downlink and the received uplink signal is strongest in the small cell – the area indicated by the dotted line in above Figure In this imbalance area, the downlink signal from the macro is strongest because it transmits at a higher power, whereas the uplink signal from the pico node is much stronger because it is closer. In this situation, coordination between the macro and pico cells for features like joint transmission and reception, such as soft handover in WCDMA, provides the user with significantly higher speeds than would be possible with separate, uncoordinated, macro and small cell layers MAKING RIGHT HETEROGENEOUS NETWORK CHOICES High-performance backhaul The various radio base station solutions used in a heterogeneous network deployment should not be limited by the backhaul solution, if possible. The level of coordination that can be achieved affects the level of spectrum efficiency, which in turn determines the quality of the user experience. to increase the level of coordination and create a high performing radio-access network, the backhaul link needs to be fast, with low latency and low latency-variation characteristics. Tighter integration between the radio-access network and the backhaul is needed to implement scalable and cost-efficient smallcell solutions, and achieve the optimal balance between radionetwork performance and coverage at a given location MAKING RIGHT HETEROGENEOUS NETWORK CHOICES Examples of such high-performance backhaul technologies are Ethernet-based line-of-sight (los) microwave and optical fiber To support multi-standard radio deployments – for example when WCDMA, LTE and Wi-Fi traffic share backhaul – the selected solutions are required to assure Qos .this Qos needs to be aligned with the Qos offered by the radio-network solution to give operators control over system performance in the event of backhaul overload or link degradation HetNet ensures higher performance HETNETS IN ACTION One size does not fit all when it comes to deploying a heterogeneous network. Instead, a flexible. Approach is needed to maximize capacity, coverage and spectrum efficiency. How to increase coverage and capacity depends on: The existing radio access and backhaul infrastructure. Site availability. Radio environment in terms of interference and mobility. The availability of radio spectrum. Time-to-market considerations. Example to Illustrate how RAN can be designed effectively Small office As with many localized indoor hotspots, it is not cost effective to install a das solution in a small office environment. Instead, a multi-standard pico radio base station supporting WCDMA, LTE and Wi-Fi – all well integrated with the macro radio-access network – provides an ideal solution. With a single base station, such a solution offers seamless access for spaces with a considerable number of highly active smart phone users. By using this approach subscribers are given a premium service locally, while the operator increases overall network capacity due to valuable and significant offloading of the outdoor macro network Conclusion A heterogeneous network – based on a single-vendor, 3gPP- standardized and coordinated radio network with integrated Wi-Fi, advanced traffic management and high-performance backhaul – can help deliver a consistent, high-quality and seamless mobile broadband experience. Making the right technology choices at the right time is the key for a smooth capacity expansion and with maximum efficiency.