The aircraft radio transmits at 10 W output power and can receive secure voice data. The ARC-164 data-handling capability makes it software capable. It has an embedded electronic counter-countermeasure (ECCM) anti-jam capability. The 243.000 MHz guard channel can be monitored. One model of the AN/ARC- 164 is interoperable with SINCGARS [5]. AN/ARC-220 The standard high-frequency (HF) (2.0-29.999 MHz) radio for US Army aviation. It includes secure voice and data communications on any of 280,000 frequencies. The system uses software-realized DSP. Using MIL-STD-2217, software updates can be made over a MIL-STD-1553B bus. ARC-220 data processing capabilities optionally include e-mail applications. The ARC-220 is software capable. MIL- STD-148-141A automatic link establishment (ALE) protocols improve connectivity on behalf of ARC-220 users. ALE executes in microprocessors and is particularly interesting as a cognitive application because of its use of a database and its sounding of the RF environment for sensing. GPS units may be interfaced with the radio, providing geolocation information [6]. AN/VRC-99 A secure digital network radio used for high data rate applications. This 1.2-2.0 GHz broadband direct-sequence spread-spectrum radio has National Security Agency (NSA) certified high-assurance capabilities and provides users with 31 RF channels. It supports TDMA and FDMA (frequency division multiple access). The networking capabilities are software programmable. AN/VRC-99 provides digital battlespace users with the bandwidth to support multimedia digital terminal equipment (DTE) of either an army command-and-control vehicle (C2V), army battle-command vehicle (BCV), or a marine corps advanced amphibious assault vehicle (A3V) with a single wideband secure waveform that supports voice, workstation, data, and imagery with growth for video requirements [7]. (Continued) CHAPTER 2.4b Cognitive radio: The technologies required Table 2.4b-1 Selected software capable radios.-Cont'd LST-5E A software capable UHF tactical SATCOM