ata rate capabilities, and finally the ability to cycle costs, and SO forth, software was added to the system handle data under software control. designs for increased flexibility. In 2000, the Federal Communications Commission (FCC) adopted the fol- lowing definition for software radios: "A communications 2.4b.2.3 Examples of software device whose attributes and capabilities are developed programmable radios and/or implemented in software" [1]. The culmination of this additional flexibility is an SDR system, as software Several examples of software programmable radios are capable radios transitioned into software programmable shown in Figure 2.4b-2 and detailed in Table 2.4b-2. The radios and finally became SDRs. The next step along this common characteristics of these radios are their ability to path will yield aware radios, adaptive radios, and finally add new functionality through software changes and CRs (see Figures 2.4b-1 and 2.4b-2). their advanced networking capability. SUO-SAS MBMMR MBITR Falcon PSC-5 ICNIA Jaguar Leprechaun EPLRS LST-5 PRC-117 SINCGARS ASIP VRC-99 ARC-210 ARC-220 ARC-164 WSC-3 SINCGARS SoftwareCapable SoftwareProgrammable SoftwareDefined Cognitive SDR Intensity Figure 2.4b-2 Examples of software radios. The most sophisticated software control and applications are reaching cognitive levels (see Tables 2.4b-1-2.4b-3 for descriptions). 1 Note that the radios that are part of Figure 2.4b-2 and Tables 2.4b-1-2.4b-3 are based on the best available public information and are intended only to notionally indicate a distribution of some of the well-known radios. For additional, accurate information about capabilities, contact the respective manufacturers. Cognitive radio: The technologies required CHAPTER 2.4b Table 2.4b-1 Selected software capable radios. SINCGARS (Single-Channel Ground and Airborne Radio System) A family of very high frequency-frequency modulation (VHF-FM) radios that provides a primary means of command and control. SINCGARS has frequency- hopping capability, and certain US Ai