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A kind of novel method of power allocation with limited cross-tier interference for cognitive radio network (CRN) is proposed in this paper. In this method, an interference-limited power allocation algorithm based on filter bank multi-carrier-offset quadrature amplitude modulation (FBMC-OQAM) is put forward. In order to improve the energy efficiency of the entire network and protect secondary users (SUs) in the network from too much interference, cross-tier interference limit is adopted, at the same time, virtual queue is designed to transform the extra packet delay caused by the contention for the channel of multiuser into the queuing delay. Taking the energy efficiency as the objective function, a nonlinear programming approach with nonlinear constraints is innovatively proposed under the constraints of time delay and transmission power. An iterative algorithm in order to solve the problem is also put forward. In the new algorithm, the fractional objective function is transformed into polynomial form, and the global optimal solution is obtained by iteration after reducing the computational complexity. In addition, a sub-optimal algorithm is proposed to reduce computational complexity. The experimental results show that the optimal algorithm has higher performance while the sub-optimal algorithm has a lower computational complexity. The presented method has very good practical importance for the CRN. INDEX TERMS Cognitive radio network (CRN), power allocation, FBMC-OQAM, Lagrange dual. I. INTRODUCTION The cognitive radio (CR) network (or CRN) [1]-[3] is a wireless communication network composed of cognitive users. Some or all of the devices in a CR network can access authorized as well as unauthorized frequency bands. Thus, compared with traditional wireless networks, CR networks have high spectral efficiency, and this makes them a key technology for next-generation mobile communication networks. The spectrum-sharing cognitive radio network is an interference-controlled CR network that can interfere with the primary user (PU) but cannot exceed its interference temperature limit. An interference temperature limit is added to The associate editor coordinating the review of this manuscript and approving it for publication was Xianfu Lei.

During mobile edge computing, due to the movement of nodes and the exhaustion of node energy, link failure occurs thus reducing the network lifetime in the mobile ad-hoc network. When the route fails, because the single-path protocols need to restart the route discovery process, the delay of the network is greatly increased. Therefore, the multi-path routing protocol is proposed, saving the cost of route discovery. In this paper, we propose an ad hoc on-demand multi-path distance vector (AOMDV) routing protocol based on link lifetime and energy consumption prediction (named LLECP-AOMDV) for mobile edge computing. In the route discovery phase, the energy grading strategy is adopted. When the node energy is lower than the threshold, it no longer participates in the route discovery. In the routing selected phase, the path is selected based on the lifetime of the route link and the minimum energy consumption of the route. According to energy consumption, packet delivery rate, end-to-end delay performance indicators, we evaluate the comparison results. The result shows that under most network performance indicators and parameters, the proposed LLECP-AOMDV is superior to the other three protocols, which improves the network lifetime, reduces the node's energy consumption and the average end-to-end delay. The protocol is very useful for mobile edge computing. INDEX TERMS Mobile edge computing, MANET, AOMDV, energy threshold, link lifetime, energy consumption.

Fused with mobile communication, Global Navigation Satellite System (GNSS) has entered the era of indoor applications, though it was initially constructed to address the issue of outdoor or open sky navigation. A pilot channel is added to modern signals to enhance tracking sensitivity and stability. In pursuit of higher acquisition sensitivity, two algorithmsdifferentially coherent and quasi-coherent integration -are proposed and analyzed respectively to achieve pilot channel acquisition in terms of its periodicity in nature. Each detection statistics corresponding is dealt with through the study of probability density function (PDF) theoretically in the presence of expected signal (hypothesis HI) as well as in the absence (hypothesis Ho), which are verified individually by numerical evaluation or simulation. The eventual assessment is accomplished by presenting the probability of correct detection (Po) with respect to various carrier to noise density ratios (C/No) and a fixed probability of false alarm (PFA). To this end, the cross-correlation function of incoming signal and local replica is derived mathematically, and proved to be self-consistent over different accumulation time interval.

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