Which communication system is a multi-mode radio capable of line-of-sight or satellite operations?

• A. VHF Radio System
• B. SHF Secure Radio
• C. UHF SATCOM Radio System
• D. HF Crossband Radio

Answer: (C)

A radio that can do both line-of-sight and satellite communications is built to switch between direct, short-range links and a satellite relay for beyond-LOS reach. The UHF SATCOM radio system is designed for that versatility: in the LOS mode, it communicates directly with nearby radios within the UHF band, and in SATCOM mode it uses a satellite link to reach distant locations, overcoming the limitations of line-of-sight. This dual capability is what makes it the best match for a multi-mode radio that can operate with either LOS or satellite operations. The other options are more specialized or LOS-focused: VHF systems are typically line-of-sight only; HF Crossband relies on ionospheric propagation for long-range but not satellite; SHF secure radios focus on high-frequency secure transmissions, not the common LOS/SATCOM dual-mode capability described.