Vol.:(0123456789) Wireless Personal Communications https://doi.org/10.1007/s11277-019-06396-w 1 3 Efcient Spectrum Handof Using Hybrid Priority Queuing Model in Cognitive Radio Networks S. Nandakumar 1  · G. V. S. Sai Bharadwaj 1  · Divyanshu Srivastava 1 © Springer Science+Business Media, LLC, part of Springer Nature 2019 Abstract Cognitive radio networks can achieve high spectrum efciency through dynamic spectrum allocation to the secondary users (SU) by way of using primary user (PU) spectrum. An efcient handof scheme for cognitive radio networks using hybrid priority queuing model has been proposed using discretion rule. This method is divided into two parts: (1) hybrid priority queuing model with discretion rule is proposed by prioritizing the secondary users in the channel and then calculate the waiting time during the spectrum handof and (2) to obtain better efciency by reducing the waiting time, the learning rate of the second- ary users from the other users should be increased. This can be done with multi teacher apprentice learning (MAL) along with sparse regression by considering multiple users into consideration at a time instead of a single user for better efciency of the spectrum. The normalized load, arrival rate and the service time of the proposed model is compared to the existing models with respect to the average data delivery time of the users. Keywords Hybrid priority queuing model · Cognitive radio networks · Secondary users · Primary users · Multi teacher apprentice learning · Sparse regression 1 Introduction Cognitive radio networks (CRN) are based on dynamic spectrum allocation where the channels are being allocated to other users (secondary users) when a primary user is not present. By this efciency of the spectrum is increased as multiple users are using the same channels in the spectrum. In cognitive radio networks the secondary users should either leave or wait in the channel when a primary user has arrived. The secondary user will be waiting in a queue of the channel if the waiting case is considered; if the secondary user is decided to leave the channel then it should perform spectrum handof [1]. When the handof is taking place, there will be a delay because of the user shifting from one chan- nel to the other channel. This delay is calculated by two types of queuing models. That is, preemptive and non-preemptive resume priority queuing models [4]. The proposed method is a hybrid priority queuing model which is a mixed preemptive resume priority queuing * S. Nandakumar snandakumar@vit.ac.in 1 School of Electronics Engineering, VIT University, Vellore, India