Configurable RF receiver architectures

In the heterogeneous world of communication and radar systems, a steadily increasing number of technical approaches for different applications are observed. A new application on the horizon is the transmission of very high data rate streams (> 500 Mb/s) during a short time interval between moving clients. Such applications may be applicable to future intelligent traffic control systems based on R.D. Kuhne (2002) and will require the support of different standards for communication and radio location services. The high data rates require high bandwidths, which become available at millimeter wave frequencies. From an engineering point of view, we may not be unsatisfied with a growing number of tasks, however, economic aspects are forcing us to search for unified solutions that do not require reengineering for every new or modified application. Therefore, the goal is to shift functionality from hardware to software. For example, channel selection and demodulation can be implemented as software codes and are no longer hardware realizations. These software-defined radios (SDRs), which compute classical receiver functions, can be reconfigurable. Therefore, the need for hardware solutions that can handle several standards and related software implementations arises. It is the purpose of this article to compare two very promising solutions (sampling and six-port) with respect to their suitability in the millimeter-wave range and to discuss some related research aspects.