A cross‐layer study for application‐aware multi‐hop cognitive radio networks

Abstract

Satisfying the different requirements of applications is important in multi-hop cognitive radio networks, because the spectrum resources change dynamically and the requirements for various applications could be very different. In this paper, we propose new schemes of channel allocation and route selection for real-time and non-real-time applications to tackle this challenge. Our scheme is flexible so that it can adapt to the different application requirements, and it can provide enough throughput while maintaining the packet loss rate and transmission rate requirements. First, we give the network model in a cognitive radio network environment, and show how to calculate the capacity of the route in multi-hop cognitive radio networks. Second, we formulate optimization problems to fulfill the rate requirements of different applications for each unicast session. We also consider the primary user activities, channel availability, interface and interference constraint. We propose the corresponding routing and channel allocation schemes for different application scenarios. Third, we propose an admission control scheme to study the impact of application requirements for multiple sessions in cognitive radio networks. Finally, we implement simulations to show the performance of our schemes and compare them with existing schemes.

A game theoretic approach for energy‐efficient communications in multi‐hop cognitive radio networks

“…Each primary user works on one channel and the primary user activity on channel c at each time slot t can be denoted as A c ( t ), (1≤ c ≤ C ), where C is the number of channels (primary users). When A c ( t ) = 1, primary user on channel c is ON, which means that the transmission of the secondary users might have interference to the primary users; when A c ( t ) = 0, primary user on channel c is OFF, which means that the channel is available and the transmission on this channel will not interfere with the primary user . In this paper, we assume that a secondary user can only use a portion of a primary user's bandwidth when the primary user does not use that portion.…”

A delay‐centric parallel multi‐path routing protocol for cognitive radio ad hoc networks

“…An on‐demand local table at each CR network node was built to determine trend of paths from source to destination. The paper proposed new schemes of channel allocation a route selection for real‐time and non‐real‐time applications in multi‐hop CR networks, which guaranteed the quality of service requirements for different types of applications. The paper investigated the problem of streaming multiple videos over multi‐hop CR networks that considered spectrum sensing and sensing errors, spectrum access and PU protection, video quality and fairness, and channel/path selection for concurrent video sessions.…”

“…The presence of PUs in CRAHNs introduces new challenges to routing metric design, route selection, and traffic assignment, which make routing in CRAHNs fundamentally different from that in traditional multi‐channel multi‐radio multi‐hop wireless networks. There already are several works on routing protocols for CRAHNs . Unfortunately, these works are all single‐path routing protocols, which have not fully exploited path diversity in CRAHNs.…”

Spectrum-Efficient Resource Allocation in Multi-Radio Multi-Hop Cognitive Radio Networks

“…Apparently, to realize cognitive radio networks (CRNs), spectrum sensing and spectrum management are two important building blocks that have been extensively studied in single-hop CRNs. However, in the last few years, researchers have gained a great deal of interest in investigating the multi-hop CRN [8,9,10,11,12,13,14,15,16,17,18]. The major reason is that wireless nodes can communicate with each other over long distances by forming multi-hop links [8].…”

“…Nevertheless, the successful implementation of a multi-hop CRN requires a clear recognition of the internal distinction between single-hop and multi-hop CRNs. Thus, as stated in [9], the crucial technical difference between single-hop and multi-hop CRNs comes from two aspects: routing and spectrum allocation.…”