Wireless Powered Cognitive-Based Mobile Edge Computing With Imperfect Spectrum Sensing

Abstract

Most mobile edge computing (MEC) works assume that the mobile devices (MDs) can offload their tasks to the MEC-severs at anytime, which may not be a practical assumption due to the tension between a large number of MDs and the scarce spectrum resources. In this paper, a framework for wireless powered cognitive radio (CR)-based MEC-enabled networks is proposed, which integrates three technologies: MEC, CR, and wireless power transfer (WPT). CR technology with imperfect spectrum sensing is adopted by the MD to find the spectrum access opportunities. An optimization problem is formulated to maximize the average calculated number of bits (CNoB) of the MD, which is non-convex and hard to solve. A two-loop procedure using a one-dimensional line search method is proposed. The time for spectrum sensing, WPT, energy harvesting (EH) and offloading, the central processing unit (CPU) frequency, and the transmit power of the MD are jointly optimized. Some semi-closed form solutions are obtained through Lagrangian dual decomposition and successive pseudo-convex approximation (SPCA) methods. Simulation results are presented to show the effectiveness of the proposed CR-based MEC scheme with different parameters.INDEX TERMS Mobile edge computing, cognitive radio, imperfect spectrum sensing, wireless power transfer, semi-closed form.

A Survey of Multi-Access Edge Computing in 5G and Beyond: Fundamentals, Technology Integration, and State-of-the-Art

“…Specifically, the authors proposed a new algorithm to minimize the required energy under the constraints on required information transmissions and processing rates. The work in [124] studied imperfect spectrum sensing in cognitive radio MEC with WPT. Specifically, a joint CPU frequency control, time power allocation problem was formulated and solved via a number of techniques, including dual decomposition, 1-dimensional search, bisection and subgradient method.…”

Secure MISO Cognitive-Based Mobile Edge Computing With Wireless Power Transfer

“…However, no detailed studies have been undertaken. A CR-WPT MEC system was considered in [20], [21], both cooperation [20] and the noncooperation [21] scenarios between the PU and the MD were studied, the computation efficiency [20] and the number of computation bits (NCB) [21] of the MD were maximized, respectively.…”

Robust Secure Wireless Powered MISO Cognitive Mobile Edge Computing

“…Obviously, WPT, CR and MEC can be combined to construct a WPT-CR based MEC system, which can simultaneously alleviate the energy and the spectrum limitations of the MEC. A WPT-CR based MEC system was studied in [12], [13], [16]. In [13], the MD sensed the status of the primary transmitter (PT) and adjusted its parameters based on the sensing results to access the spectrum for WPT and task offloading.…”

“…A WPT-CR based MEC system was studied in [12], [13], [16]. In [13], the MD sensed the status of the primary transmitter (PT) and adjusted its parameters based on the sensing results to access the spectrum for WPT and task offloading. In [12], a cooperation mode was considered in WPT-CR based MEC system.…”