In an article entitled, "Software Defined Radio Flexible Air Interface" that appeared in the April 27 issue of the IMEC Scientific Report, Dr. Liesbet Van der Perre, scientific director, of wireless research at IMEC in Leuven, Belgium discussed how software-defined radio (SDR) terminals will become crucial in enabling seamless and transparent inter-working between various wireless access systems and communication modes.

He expects that future wireless systems of the fourth-generation (4G) will support a wide variety of services over a wide variety of networks in ways transparent to the user.

On the longer term, SDRs will be extended to become cognitive radios coupling energy savings to efficient spectrum usage. The SDR `flexible air interface' (FLAI) project plans to deliver SDR baseband solutions for nomadic terminals, with a cost- and power-efficient integrated architecture supporting all radio standards from CDMA (3GPP-LTE), up to the most demanding OFDM-based communication standards (802.11n, 802.16e, DVB-H).

This goal is achieved with a heterogeneous multiprocessor system-on-chip platform for the baseband processing, and algorithmic solutions to bring standards real-life wireless, including synchronization and analog front-end non-ideality compensation—crystal frequency offset, IQ imbalance, phase noise techniques—to achieve a high spectral efficiency at low cost and power. Scalability is provided in the architecture and in the algorithms, to enable trading off performance/power.

A multiprocessor system-on-chip (MPSoC) platform is proposed as best suited to match the requirements. The digital baseband platform achieves functional flexibility and energy efficiency through partitioning. The subfunctions are divided according to their nature and flexibility/energy efficiency requirements. The multiprocessor SoC includes a digital baseband front-end to implement packet detection.

IMEC (Interuniversity Microelectronics Center) is a microelectronics research facility on the outskirts of Leuven, Belgium with affiliated laboratories throughout Flanders. IMEC focuses on next-generation electronics research, about three to 10 years ahead of industrial needs. The organization employs approximately 1400 people.