Erasure Correcting Codes for Opportunistic Spectrum Access (OSA).
- Authors
- Publication Date
- Jul 01, 2014
- Source
- HAL-UPMC
- Keywords
- Language
- English
- License
- Unknown
- External links
Abstract
The emergence of new devices especially the smartphones and tablets having a lot of new applications have rocketed the wireless traffic in recent years and this is the cause of main surge in the demand of radio spectrum. There is a need of either more spectrum or to use existing spectrum more efficiently due to dramatic increase in the demand of limited spectrum. Among the new dynamic access schemes designed to use the spectrum more efficiently opportunistic spectrum access (OSA) is currently addressed when one or more secondary users (SU) are allowed to access the channel when the PU is not transmitting. The erasure correcting codes are therefore envisioned to recover the lost data due to sensing impairments. We define the parameter efficiency of SU and optimize it in-terms of spectrum utilization keeping into account sensing impairments, code parameters and the activity of PU. Finally, the spectrum access for multiple secondary users is addressed when there is no primary and each user has equal right to access the channel. The interesting scenarios are Cognitive radio networks and WiFi where 802.11 protocol gives the specification for MAC layer. The throughput curvesachieved by retransmission and using various erasure correcting codes are compared. This modification in MAC layer will reduce the long waiting time to access the channel, as the number of users are increased.
