DREW

Purpose and goal

Broadband receivers are key components in the majority of Saab´s electronic warfare products and Ericsson´s development of telecom products. Todays demands to lower cost and size, the need for extremely broadband digital receivers is increasing. A successful collaboration between LTH, Ericsson and Saab that began with comprehensive studies has shown that by replacing parts of traditional microwave electronics with commercial Sample-and-Hold circuits, this technology shift can succeed in pushing down both cost and size of the end product.

Expected results and effects

Initial studies concluded that for extremely wideband digital receivers different bottlenecks exist depending on frequency range. In the low-GHz region, unwanted signals within the sought RF spectrum cause degraded dynamic range of digital receiver. Which resulted in the design of a novel low noise 2-6 GHz RF front-end. For higher frequencies the main limiting factor was identified to be the limited spurious free dynamic range of existing S/H solutions. Evaluation of existing 2-18 GHz S/H circuits show that they are possible to utilize in sought application up to and beyond 20 GHz.

Planned approach and implementation

The work was performed with each party´s participation in studying system requirements, examining appropriate architectures and requirements for integrated digital receivers. The knowledge and experience that exists among the participants at Saab, Ericsson and Lunds Universitet in radio systems and integrated digital receivers has made it possible to design, implement and manufacture integrated circuits in advanced CMOS MMIC process. The project characterized commercial S/H circuits, built demonstrators and made initial S/H simulations in the available GaAs MMIC process.