A Software-Defined Radio (SDR) is any collection of hardware and software that enables a single radio to be quickly and easily reconfigured to a desired standard. Until now, software-defined radios (SDRs) were reconfigured by installing new software on built-in RISC or DSP chips, creating multimode, multiband, multifunction radios. But a new approach called reconfigurable logic (RCL) is emerging.
RCL is essentially any IC whose function can be changed at the gate level by applying an external command. One example is an FPGA that can be reprogrammed on-the-fly. Today's very high-density gate arrays can easily handle the special DSP algorithms required by SDRs. They also can be quickly reconfigured to support any desired function.
Under the sponsorship of the SDR Forum, more than 50 companies met to swap insights and strategies for RCL in January. Altera, Intel, QuickSilver, Xilinx, and others examined the current state of the RCL architecture and functionality as it applies to SDR. Widespread adoption of RCL depends on the software tools and intellectual-property (IP) core software that implements the various radio functions and standards.
So far, SDRs have primarily served as military radios. Ultimately, though, their manufacturers have their sights set on much more, including cell-phone basestations and handsets and eventually public-service radios used by police and firefighting services.