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With increased activity in the horizon, the T&M vendors, nevertheless, seem to be stuck with pressure on price points, yearly maintenance costs, high import duties, and frequent hardware and software upgrades.
With an ongoing increase in subscriber base, as operators move toward 3G, WLAN, LTE, LTE-A, R&D investments in the ongoing LTE and LTE-Advanced technologies fuel demand for test and measurement instruments and test solutions to optimize the networks.
The LTE/LTE-Advanced technology is continuously enhanced either by adding new technology components or by improving the existing ones. LTE-Advanced as specified in the 3GPP Release 11 timeframe comprises a number of improvements based on the existing features, like LTE carrier aggregation enhancements or further enhanced ICIC.
Testing of LTE-Advanced technology components. The different technology components of LTE-Advanced have different market priorities and require different testing strategies. Generally, each of the LTE-Advanced technology components can be considered as single optional feature to be supported on both infrastructure and end-user device side - whether or not to implement carrier aggregation in the network is driven by operator requirements and infrastructure manufacturer implementation capabilities. Likewise, the implementation of various LTE-Advanced features at the user device side depends on the individual chip set and user device manufacturer plans. The testing of each aspect may be considered. However, this does not prevent the implementation and consequently testing of multiple features in a single Device Under Test (DUT). Relaying is not considered here, as it was not completed in 3GPP Release 10 timeframe but moved to 3GPP Release 11.
Carrier Aggregation (CA) introduces the capability to aggregate up to five LTE Release 8 carriers, although practical implementations specifically at the terminal side are restricted to two DL carriers and one UL carrier (potentially also two UL carriers). Three different modes of carrier aggregation exist within LTE-Advanced:
Intra-band contiguous
Intra-band non-contiguous
Inter-band
Intra-band describes the aggregation of component carriers within the same frequency band in a contiguous or non-contiguous way. For inter-band carrier aggregation the two component carriers reside in different frequency bands. For carrier aggregation the main test challenge from RF perspective is to verify simultaneous transmission of multiple carriers in terms of modulation accuracy or unwanted inter-modulation products. Additionally, components like power amplifier need to work with the required number...