During the LTE Masterclass at the LTE World Summit in Barcelona, Ajay Khanna, CTO and VP of Engineering, discussed the challenges of rolling out an efficient and profitable LTE network on top of the existing 2G /3G technologies and multiple vendor equipment deployments.
Recently we have seen a huge growth in demand for data, caused by the explosion in new devices and applications, and operators are looking towards LTE to provide the increased capacity that is required. Deployment figures for LTE are already impressive – out of 258 networks scheduled to be deployed, by mid-May this year 72 were already operational. This growth has a major impact on networks – not only is it difficult to manage a multi-technology network (2G, 3G, and 4G) because of the complexity, but also more than ever there is a need to deliver a high quality experience to the user. Is there a better way to increase operational efficiency and provide subscribers with the data capacity and quality of experience they need? Multi-technology self-optimising networks (SON) solutions can help.
As 3G and 4G networks continue to grow, network management will become increasingly challenging. Under traditional network management procedures, the optimisation engineer has to analyse the status of the network each morning using several disparate tools and assess the impact of alarms, service tickets etc. before manually optimising the network. As the networks become more complex, this approach is becoming unsustainable and inefficient. So, is multi-vendor, multi-technology SON merely a desire, or is it now becoming a necessity? Celcite’s strong view on this is that multi-technology SON solutions are an absolute necessity for operators to efficiently manage and optimise their networks.
Celcite’s approach to SON is that of a closed loop system (see illustration). Various interfaces collect data – traces and mobile measurements, raw performance counters, site data, trouble tickets and so on ‑ and input these into the SON framework. The SON Monitor in the framework compares the data against the operator’s KPIs and determines which SON function needs to be triggered in order to improve the KPIs. A key ingredient of Celcite’s SON is our Automatic Intelligent Correlation (AIC) engine. AIC tracks the top offender list and performs a root cause analysis, highlighting and reporting discrepancies and making engineering recommendations resulting in executable solutions and automatic scripts.
Typical use cases where SON can help the operator include:
1) Self optimisation by Automatic Neighbor Relations (ANR) which enables the addition, removal or re-prioritisation of neighbors in the network
2) Automatic Load Balancing (LB) which alleviates network congestion based on the cell load using several parameters
3) Self-Healing (SH) function which responds to an outage alarm by changing the coverage footprint of neighboring cells, as well as implementing parameter changes
4) Automatic Parameter Optimisation (APO) which changes various parameters that will improve network KPIs, as well as accommodate new sites coming on air.
For each of the SON functions, the operators can set their own thresholds for triggering adjustment of the parameters, based on their judgment of the effects on customer experience and how much variation the network can tolerate before efficiency is compromised.
In conclusion, the benefits of multi-technology, multi-vendor SON are numerous. They include improved network quality and customer satisfaction; increased operational efficiency; CAPEX and OPEX savings; and provide better network control and management across multiple vendors. Furthermore, SON can also co-exist with and complement RAN vendors’ proprietary SON solutions, which in themselves are much more limited in their scope – they cover LTE only, not inter-RAT, and are only applicable to that single vendor’s equipment. Celcite believes multi-vendor, multi-technology SON is the next key step to ensure operator profitability and survival.