Name
Abstract | ||
|---|---|---|
Cognitive Radios have been advanced as a technology for the opportunistic use of under-utilized spectrum since they are able to sense the spectrum and use frequency bands if no Primary user is detected. However, the required sensitivity is very demanding since any individual radio might face a deep fade. We propose light-weight cooperation in sensing based on hard decisions to mitigate the sensitivity requirements on individual radios.We show that the "link budget" that system designers have to reserve for fading is a significant function of the required probability of detection. Even a few cooperating users (similar to 10-20) facing independent fades are enough to achieve practical threshold levels by drastically reducing individual detection requirements. Hard decisions perform almost as well as soft decisions in achieving these gains. Cooperative gains in a environment where shadowing is correlated, is limited by the cooperation footprint (area in which users cooperate). In essence, a few independent users are more robust than many correlated users.Unfortunately, cooperative gain is very sensitive to adversarial/failing Cognitive Radios. Radios that fail in a known way (always report the presence/absence of a Primary user) can be compensated for by censoring them. On the other hand, radios that fail in unmodeled ways or may be malicious, introduce a bound on achievable sensitivity reductions. As a rule of thumb, if we believe that 1/N users can fail in an unknown way, then the cooperation gains are limited to what is possible with N trusted users. |
Year | DOI | Venue |
|---|---|---|
2006 | 10.1109/ICC.2006.254957 | 2006 IEEE INTERNATIONAL CONFERENCE ON COMMUNICATIONS, VOLS 1-12 |
Keywords | Field | DocType |
probabilistic analysis,indexing terms,system design,rule of thumb,face detection,spectrum,cognitive radio,robustness,shadow mapping,computer science,fading,probability of detection | Link budget,Fading,Computer science,Computer network,Shadow mapping,Robustness (computer science),Rule of thumb,Face detection,Radio spectrum,Cognitive radio | Conference |
ISSN | Citations | PageRank |
1550-3607 | 617 | 102.55 |
References | Authors | |
2 | 3 | |
Name | Order | Citations | PageRank |
|---|---|---|---|
| Shridhar Mubaraq Mishra | 1 | 830 | 117.53 |
| A. Sahai | 2 | 1888 | 198.31 |
| Robert W. Brodersen | 3 | 1857 | 401.31 |