Feb 27, 2012 - Rohde & Schwarz and Cognovo to demonstrate realtime LTE-Advanced testing at Mobile World Congress 2012.
Rohde & Schwarz and Cognovo will demonstrate a realtime 3GPP Release 10 LTE-Advanced downlink scenario using the R&S®SMU200A vector signal generator, the R&S®EX-IQ-Box digital signal interface module, the R&S®FSW signal and spectrum analyzer and the Cognovo software defined baseband chip.
The demonstration – hosted at the Rohde & Schwarz booth, 1E51, in hall 1 – shows the R&S®SMU200A providing a fully 3GPP Release 10 compliant carrier aggregation signal, where two 20 MHz OFDM carriers are decoded by the Cognovo baseband device to deliver data bandwidth equivalent to 40 MHz. The R&S®FSW provides the RF characterization of the signal using its up to 160 MHz analysis bandwidth.
The R&S®SMU200A vector signal generator enables creation of arbitrary intra- and interband carrier aggregation scenarios using its two basebands. The new R&S®SMU-K85 software option makes it possible to generate a signal with up to five LTE-Advanced component carriers, where each carrier can be configured with a flexible bandwidth from 1.4 MHz to 20 MHz as well as with an individual cell ID, power, time offset and frequency offset. Cross-carrier scheduling in accordance with 3GPP Release 10 is also supported. The new R&S®FSW signal and spectrum analyzer provides all relevant RF measurements on each individual carrier, including modulation accuracy, power vs. time, and spectrum mask. The large 12.1-inch touchscreen allows users to configure the measurements and can display multiple measurement results simultaneously.
Wolfgang Kernchen, Director of the Signal Generators, Audio Analyzers and Power Meters Subdivision at Rohde & Schwarz, commented: “Closing the loop between simulation, development and validation is essential to maintaining the industry’s pace of innovation. Rohde & Schwarz has a reputation for working at the edge of innovation, and this partnership with Cognovo enables us to demonstrate real-world testing as early as possible in the design flow.”
The Cognovo CDC160 chip, together with the associated development platform (CDP), enables wireless developers to create a complete multimode modem design in software before they finalize their production baseband device. The chip is currently being used by customers developing modems for LTE and LTE-Advanced.
Pascal Herczog, CTO at Cognovo, said: “Bringing any new wireless standard to market presents a significant engineering challenge, since reliable test equipment and a realtime platform are both needed early on in the program, so that we can move beyond simulation models and explore real-world performance and optimization. This has become critical with newer standards such as LTE-Advanced, where die size, cost, power consumption and performance must be optimized during the design stage. The Cognovo CDP and integrated tool chain makes it possible to optimize and validate the modem at an early stage.”
LTE-Advanced specifies several extensions to the LTE standard, increasing bandwidth to 1 Gbyte/s in the downlink. These extensions are known as carrier aggregation, extended MIMO, enhanced ICIC supporting heterogeneous network deployments and enhanced uplink transmission. The most talked about of these – carrier aggregation – is seen by many as the key to realizing LTE’s mobile broadband promise and is already being planned into service rollout as early as 2013.
3GPP LTE Release 8 enables up to 150 Mbit/s downlink – shared by each user within a given sector – but in many cases, mobile carriers can only implement a fraction of this. In North America, for example, where spectrum is fragmented, channels of only 5 MHz or 10 MHz are commonly available, rather than the maximally defined 20 MHz. Furthermore, spectrum is often noncontiguous, with channels being spread across several bands; as the demand for new services drives new spectrum allocation, spectrum often becomes available in even more bands.
Carrier aggregation is important because it allows the baseband device to receive multiple parallel streams and aggregate them to create a wider channel, e.g. 5+5 MHz, 5+10 MHz, 20+20 MHz, etc. This scalability operates across contiguous and noncontiguous bands, allowing carriers to exploit their spectrum efficiently and dynamically to give users required bandwidth and quality of service regardless of the size or location of individual radio channels. Several carriers have already announced deployment as early as next year.