Cognitive Radio/ CR

Definition

Cognitive Radio extends SDR with a sensing and decision loop that continuously evaluates spectrum occupancy, link quality, and threats, and re-tunes the waveform to maintain communication. In contested environments, cognitive radios autonomously hop frequencies, change modulation, or switch waveforms to evade jamming. DARPA's Spectrum Collaboration Challenge is the canonical reference event for the technology class.

Reference attributes

Loop

Sense, decide, adapt

Adapts

Frequency, modulation, power, coding

Reference program

DARPA Spectrum Collaboration Challenge

Related terms

• Software-Defined Radio (SDR)
  Radio whose physical-layer behavior is defined in software, enabling waveform reprogramming.
• Dynamic Spectrum Access (DSA)
  Real-time, opportunistic use of spectrum based on sensing and policy.
• Anti-Jam Techniques (AJ)
  Waveform and protocol techniques that preserve link integrity under deliberate jamming.