Performance Enhancement for Multihop Cognitive DF and AF Relaying Protocols under Joint Impact of Interference and Hardware Noises: NOMA for Primary Network and Best‐Path Selection for Secondary Network

Abstract

In this paper, we propose and evaluate performance of multihop multipath underlay cognitive radio networks. In a primary network, an uplink nonorthogonal multiple access method is employed to allow primary transmitters to simultaneously transmit their data to a primary receiver. Using an underlay spectrum-sharing method, secondary source and secondary relays must adjust their transmit power to guarantee quality of service of the primary network. Under the limited transmit power, cochannel interference from the primary transmitters, and hardware noises caused by impairments, we propose best-path selection methods to improve the end-to-end performance for the secondary network. Moreover, both multihop decode-and-forward and amplify-and-forward relaying protocols are considered in this paper. We derive expressions of outage probability for the primary and secondary networks and propose an efficient method to calculate the transmit power of the secondary transmitters. Then, computer simulations employing the Monte-Carlo approach are realized to validate the derivations.

On the Performance of Cellular Networks with Adaptive Modulation and Energy Harvesting—A Stochastic Geometry Approach

“…Meanwhile, the closed-form expression of ergodic capacity in multi-hop decode and forward (DF) was given in [11]. Duy and others in [12] derived outage probability expressions in cognitive radio networks. Moreover, the transmit power of the secondary transmitter was computed in [13].…”

An Optimized Distributed Routing Protocol for Energy Management Systems Based on Wireless Sensor Networks in Intelligent and Smart Structures

“…In [23], the authors evaluated the performance of dual-hop CR WSNs in the existence of hardware noises and proposed three relaying algorithms, namely, best ORS (B-ORS), conventional ORS (C-ORS), and hybrid PRS (H-PRS) protocols. However, researchers proposed a better PRS scheme, where CSIs of the relay-destination connections are used to choose the relay [24]. In [23][24][25][26][27][28][29], several relay selection methods have been described in CR networks.…”

“…However, researchers proposed a better PRS scheme, where CSIs of the relay-destination connections are used to choose the relay [24]. In [23][24][25][26][27][28][29], several relay selection methods have been described in CR networks. Especially in [23], the PRS and ORS methods evaluated the overall performance in terms of bit error rate (BER) and outage probability (OP).…”

“…In [32], the authors give a detailed analysis of the performance of a two-way CR EH-TWCR wireless network (EH-TWCR), which is based on decodeand-forward (DF) in the existence of transceiver limitations. In [19,20,24,25,33,34], the authors proposed the performance of multihop CR wireless networks, specifically end-to-end, where PB or RF signals of the primary transmitter can be used from SUs to harvest energy.…”

“…Because of the low-cost transceiver equipment, wireless sensor nodes fall victim to hardware limitations due to amplifier nonlinearities and phase noise [24,26,35,36,43]. The performance degradation can be recovered using a cooperative relaying algorithm.…”