HF equipment: Receivers, transmitters, synthesizers, and peripherals

Although long distance communications via satellites has dominated the last two decades of radio equipment development, high frequency (HF) radio equipment is experiencing a high technology renaissance. Satellite systems now transmit quality low data rate communications and navigation aids to mobile users, but the low cost and surviability attributes of HF radio are again being recognized. Emerging new systems automate network operations while adapting to propagation conditions. However, neither new replacement radios nor new systems furnish the potential capability of state-of-the-art components. The advances in equipment, systems, and components are summarized.