The TM500 network test system, available from Cobham Wireless, now includes support for 256 QAM modulation – one of the features of LTE-Advanced (LTE-A) which is being introduced in 3GPP Release 12. The use of this modulation scheme in combination with carrier aggregation (CA) in the downlink, boosts data rates up to 600 Mbps and allows network operators to improve spectrum efficiency for mobile terminal devices under favourable operating conditions.
Increasing the modulation order to 256 QAM provides a 33 percent increase in LTE-A data rate compared with 64 QAM. The higher data speed (256 QAM) in conjunction with carrier aggregation and two layers of MIMO enables theoretical data rates of up to 600 Mbps, which is applicable to small cell deployments where users are close to the base station and high signal-to-noise ratios can be achieved. Support for 256 QAM over multiple aggregated carriers allows complex mobility scenarios including a mixture of mobile terminals operating to different 3GPP Release standards. This is accompanied by enhanced mobility models to reflect the challenging operational and mobility scenarios that occur with higher modulation orders.
Downlink 256 QAM support is available as a software upgrade for existing TM500 customers, which gives infrastructure vendors the capability to validate networks under a range of realistic usage scenarios and to determine where the use of the higher order modulation scheme will improve customer experience. The real world of mixed macrocell and small cell combinations provides a complex RF environment for validating the correct operation and performance of dynamically changing modulation schemes. The ability to create a realistic – yet controlled – environment, and to allow different levels of complexity and realism to be selected, is the key to rapid feature deployment. As 256 QAM is rolled out with LTE-A networks, the TM500 network test system will enable network operators to validate both the underlying feature performance and the impact upon end user experience using real data traffic applications.
Benefits of the TM500 network test system
Operating across all the 4G frequency bands specified up to 3GPP Release 12, the TM500 network test system provides end-to-end testing from RF to application layer, validating KPIs to optimize quality of service (QoS) and quality of experience (QoE) under realistic traffic and mobility scenarios, including real-life UE modelling and fading channel models, in a single unit. www.cobham.com/wireless