Overview

In the late 1990s, nearly all telecommunications radios were built using digital signal processor (DSP) processors to implement modulation and signal processing functions, and a General Purpose Processor (GPP) to implement operator interface, network signaling, and system overhead functions. This architecture is attractive to a manufacturer because the same basic electronics can be used over and over for each new radio design, thereby reducing engineering development, enabling volume purchasing, and optimizing production of a common platform, while retaining the flexibility for sophisticated waveforms and protocols. A few manufacturers called their radios Software Defined Radios (SDRs), recognizing the power and market attractiveness of the customer community being able to add additional functionality that is highly tuned to market specific applications.

In the early 2000s, a few of these vendors made application layer software functionality available for additional value added functions to aid the user. Users could add music, games, or other applications, as long as the radio waveform functions remained untampered.

Similarly, in the late 2000s, many radios will make the software functionality available for various classes of adaptivity and significantly extend user support functionality. This will initiate the generation of Cognitive Radios . Thus, with minimal additional hardware, additional software features will enable users, network operators, spectrum owners, and regulators to accomplish much more than with the fixed application radios of an earlier generation.

To understand this important design trend, we must...