Sequence Detection in Dynamic Spectrum Access Networks.
This technology avoids the shortcoming of energy detection which can be ineffective in high noise, low SNR environments.
Secondary users of a licensed radio band need a reliable means of detecting the primary users’ presence. Optimally sharing a communication channel requires accurately finding holes in the PU’s transmission. Knowing both when a SU can and cannot transmit allows both users to maximize data transmitted. TECHNOLOGY: The PU access pattern is exploited in order to benefit channel access by the SU. Errors involved in sensing PU access involve both missed detections, causing interference, and missed openings, unnecessarily limiting the SU. Both errors can be weighted to account for the different cost factors experienced by a SU on a PU’s channel. Decision making by the SU is improved over time as the PU access pattern is developed. A forward-algorithm is used to calculate an on/off estimate for the PU and can be combined with a backward algorithm to increase predictive accuracy. PU sensing is conducted in order update the predicted state of the PU and improves system performance.
- Avoids the shortcoming of energy detection which can be ineffective in high noise, low SNR environments. - Weight factors can be modified to account for systems costs, constraints, and specific channel regulations. - PU state change in the middle of a sensing window can be modelled for further exploitation by the system.