Chaitanya Chakravarty . M, Application Engineer-Wireless, Electronic Measurement Group, Agilent Technologies India Pvt. Ltd.

Results in many surveys depict that the network operation cost is about 20 percent of the overall OpEx. To be in the race with increasing demand for mobile broadband, operators need solutions to rapidly expand and quickly deploy additional radio capacity and coverage. Traditionally, deployments involve manual processes to configure and optimize new cell sites. To reduce this, automation is required at the planning stage and also during configuring cell sites. Automation helps in speeding up deployment by reducing the risk of manual errors. With the help of automation, operating costs fall and the services delivered to consumers improve.

SON in an LTE network can help in configuring and optimizing network coverage, capacity, cell size, topology, frequency allocation, and bandwidth, based on changes in interference, signal strength, location, and traffic pattern and also can help reduce human interactions. SON helps operators save operational expenditures by eliminating manual configuration of equipment at the time of deployment, right through to dynamically optimizing radio network performance during operation.

SON has some key features like automatic neighbor relations (ANR), mobility load balancing (MLB), and mobility robustness optimization (MRO). ANR helps automatic discovery of new neighbor eNodeBs via UE assistance. MLB allows tuning handover thresholds between cells based on cell loading. MRO monitors failed handovers to fine tune mobility parameters. These SON features enable optimal mobility and network load balancing in LTE, which reduces the operational effort.

On challenges vis-?†-vis testing the present-day networks

Presently, most of the networks deployed use two or more radio technologies. Operator's networks have a mixture of equipment from several vendors and multiple (radio) nodes with a range of different characteristics. For example, GSM, W-CDMA, HSPA, and LTE multi-carriers can now be simultaneously transmitted from a single multi-standard radio (MSR) base-station unit. These networks are complex and have challenging operating environment. As mobility carriers embrace to a new technology, new equipment must co-exist with older standards. MSR testing characterizes these interactions. Traditionally, RF specifications for base station transmitters and receiv¬?ers have been developed separately for different radio access technologies (RATs). However, in an MSR base station, the base station transmitter and receiver are capable of processing multiple carriers of different RATs simultaneously using com¬?mon RF hardware, requiring a new set of RF specifications.

3GPP developed a dedicated RF specifica¬?tion for MSR-capable base stations in the 3GPP Release 9 (TR/TS 37 series). Trans¬?mitter measurements in a multi-RAT configuration include channel power, modulation quality (EVM), frequency error, spurious emissions, and operat¬?ing band unwanted emissions (SEM), while the adjacent channel leakage ratio (ACLR), occupied BW, and time alignment between transmitter branches are performed in single-RAT configurations, as defined in TS37.141 conformance requirements. Agilent provides a powerful MSR test and design solutions including single button embedded measurement applications in accordance with 3GPP Rel.9.

On growth plans for FY 2012-13

One of the key growth drivers beyond 2012 will be the wireless boom and digital convergence on mobile. The future of wireless will be riding on 3G and WiMAX/LTE deployment and value-added services. All services like Internet banking, stock trading, web surfing, video conferencing, m-banking, and m-health are moving toward mobile networks. National Telecom Policy would also play an important role in shaping up this industry moving forward. Technologies prevailing in the Indian market are 2G, 3G, and WiMAX/LTE, and for these technologies, most chipset designers, protocol stack developers, and telecom manufacturers are increasing their RF test capabilities in India.

This provides opportunity to a company like Agilent Technologies, which already has a wide range of testers for R&D, manufacturing, and installation/deployment segments.