NM - 2.01 Cognitive Radio Flashcards
Describe the evolution of radio
Firmware -> SDR -> Cognitive Radios -> Cognitive Networks
What’s SDR
A collection of hardware and software technologies that enable reconfigurable system architectures for wireless networks and user terminals.
Provides substrate for cognitive radio. In an ideal world, the only HW we want is an antenna.
What’s Cognitive Radio
A Tx that is aware, adaptive and capable of learning from experience
Aware
- RF environment
- Own capabilities; how much power, how much to process, operational status
- Policies it needs to follow
- Local and global objectives
- Of network conditions; traffic peak, bottleneck
- Users’ priorities and authorisations
Adaption
- Change no. of antennas
- Change modulation schemes
- Routing
- Negotiation of waveforms and protocals
Learning
- ML algo
- Experience-weighted table lookup; co-define what must be done -> low (BPSK), Medium (QPSK), Good (16-QAM)
Name the desirable features
- Wideband; DC to Davylight -> flexible
- Any waveform
- Flexible architecture
- High performance and low power consumption
- Affordable and accessible
- Straightforward to use
- Robust
What does Radio front end deal with?
Front end deals with frequency, filtering and power
What does Radio and Signal Processing Software deal with?
Software handles waveforms and protocals
Name some cognitive radio applications?
- Dynamic spectrum access
- Cooperative medium access and cooperative communications
- Oppurtunisitic switching among available wireless networks
- Adaptive selection of available radio resources
- Increased interoperability of different systems
How do we do spectrum sharing?
Overlay - Opportunistic
Explain self-organising networks
What are self-organising networks?
- Automatically extend, change, configure and optimize their:
- Topology
- Coverage
- Channel allocation
- Excellent scalability, robustness
