Since 5G new radio comes with non-standalone (NSA) and standalone (SA) versions in 3GPP, research on 6G has been schedule by academics industries. Though is supposed to have much higher capabilities than 5G, yet there no clear description about what is. In this article, a comprehensive discussion of given based the review developments, covering visions requirements, technology trends challenges, aiming at tackling challenge coverage, capacity, user data rate movement speed mobile...

Internet of Vehicles (IoV) has drawn great interest recent years. Various IoV applications have emerged for improving the safety, efficiency, and comfort on road. Cloud computing constitutes a popular technique supporting delay-tolerant entertainment applications. However, advanced latency-sensitive (e.g., auto/assisted driving emergency failure management), cloud may result in excessive delay. Edge computing, which extends storage capabilities to edge network, emerges as an attractive...

As the traditional resources (frequency, time, space, and so on) are efficiently utilized, it becomes more challenging to satisfy ever-lasting capacity-growing users-boosting demand in wireless networks. Recently, EM wave was found possess not only linear momentum, but also angular momentum. The OAM is a kind of wavefront with helical phase. OAM-based vortex has different topological charges, which orthogonal each other, bridging new way for multiple access communications. In this article,...

As a critical step towards the next new era of mobile wireless networks, recently 5G networks have received significant research attention and efforts from both academia industry. The are expected to provide different delay-bounded QoS guarantees for wide spectrum services, applications, users with extremely diverse requirements. Since time-sensitive services in multimedia may vary dramatically large range milliseconds few seconds diversity uniform/ constant delay-bound different/variable...

Since the Information and Communications Technologies (ICT) were designed without taking energy-saving into account, unexpected excessive energy consumption of fourth-generation (4G) pre-4G wireless networks causes serious carbon dioxide emissions. To achieve green networks, fifth-generation (5G) are expected to significantly increase network efficiency while guaranteeing quality service (QoS) for time-sensitive multimedia traffics. In this paper, we develop statistical delay-bounded QoS...

By enabling very high bandwidth for radio communications, the millimeter-wave (mmWave), which can easily be integrated with massive-multiple-input-multiple-output (massive-MIMO) due to small antenna size, has been attracting growing attention as a candidate fifth-generation (5G) and 5G-beyond wireless communications networks. On other hand, communication over orthogonal states/modes of orbital angular momentum (OAM) is subset solutions offered by massive-MIMO communications. Traditional...

For unforeseen natural disasters, such as earthquakes, hurricanes, and floods, etc., the traditional communication infrastructure is unavailable or seriously disrupted along with persistent secondary disasters. Under circumstances, it highly demanded to deploy emergency wireless (EWC) networks restore connectivity in accident/ incident areas. The emerging fifth-generation (5G)/beyond-5G (B5G) system, like unmanned aerial vehicle (UAV) assisted intelligent reflecting surface (IRS) based...

As an attractive and challenging transmission mode, the wireless full-duplex can potentially double system throughput if self-interference be efficiently cancelled or suppressed as compared with that of half-duplex transmission. Recently emerged advanced cancellation suppression techniques have shown possibility avoiding overwhelmed However, to achieve in networks, not only efficient physical-layer is necessary, but also practical medium access control (MAC) protocol highly demanded datalink...

Because of the asynchronization between primary and secondary wireless networks, synchronization users (PUs) (SUs) can be hardly guaranteed in nontime-slotted cognitive radio networks (CRNs). In this paper, we propose a novel framework for multichannel CRNs, where PUs randomly access leave licensed channels. Since cannot distinguish signals, may sense busy channel when start to reactivate during SUs' transmission, thus generating collision or entering backoff stage. To guarantee...

By enabling two adjacent mobile devices to establish a direct link, device-to-device (D2D) communication can increase the system throughput over underlaying wireless networks, where D2D and cellular communications coexist share same radio resource. Traditional schemes mainly focus on maximizing without taking into account quality-of-service (QoS) provisioning. To overcome this problem, we develop framework investigate impact of delay-QoS requirement performance in networks. Then, propose...

As the fourth-generation (4G) standards have been successfully deployed in all 4G-based wireless communication industries and mobile devices, research attention efforts of academia industry already moved onto fifth-generation (5G) technologies. While frequency-division duplexing (FDD) timedivision (TDD) are widely used 4G networks, they their inherent deficiencies low spectrum efficiency because FDD TDD both based on half-duplex transmission mode. To overcome these problems existing systems,...

We consider the full-duplex transmission over bidirectional channels with imperfect self-interference cancelation in wireless networks. In particular, together using propagation-domain interference suppression, analog-domain cancellation, and digital-domain we develop optimal dynamic power allocation schemes for sum-rate optimization problem which aims at maximizing of transmissions. high signal-to-interference-plus-noise ratio (SINR) region, maximization is a convex problem. For...

Swarm of drones, as an intensely significant category swarm robots, is widely used in various fields, e.g., search and rescue, detection missions, military, etc. Because the limitation computing resource dealing with computation-intensive tasks locally difficult. Hence, cloud-based computation offloading adopted, nevertheless, for some latency-sensitive tasks, object recognition, path planning, etc., manner inappropriate due to excessive delay. Even harsh environments, disaster area,...

The emerging orbital angular momentum (OAM) based wireless communication is expected to be a high spectrum-efficiency paradigm solve the growing transmission data rate and limited bandwidth problem. Academic researchers mainly concentrate on OAM-based line-of-sight (LoS) communications. However, there exist some surroundings around transceiver in most practical scenarios, thus forming multipath transmission. In this paper, hybrid orthogonal division multiplexing (HODM) scheme by using OAM...

Airborne mobile wireless networks (AMWNs), which use spacecrafts and aircrafts such as satellites, airships, airplanes, unmanned aerial vehicles, other high/medium/low-altitude platforms (HAPs/MAPs/LAPs) can efficiently support high dynamic network topologies weakly connected communication links. Due to the dramatic dynamics of AMWNs, it is very difficult provide deterministic delay-bounded quality service (QoS) provisioning for time-sensitive real-time traffics (such video audio) over...

Frequency hopping (FH) has been widely used as a powerful technique for antijamming in wireless communications. However, the spectrum is becoming more and crowded, it very difficult to achieve efficient results with FH-based schemes. Orbital angular momentum (OAM), which provides new angular/mode dimension communications, offers an intriguing way antijamming. In this paper, we propose use orthogonality of OAM-modes particular, mode (MH) scheme within narrow frequency band. We derive...

Orbital angular momentum (OAM) waves with different modes usually perform divergence angles, leading to a big challenge and high complexity for signal receiving. To address this issue, letter presents novel antenna array generating four-mode OAM equal angle. In the proposed antenna, center patch three concentric uniform circular arrays (UCAs) are employed carry 0, -1, -2, -3 from outer rings, respectively. Each UCA is carefully optimized control mode propagate along same validate design,...

Facing the dramatic increase of real-time applications and time-sensitive services, large-scale ultra-low delay requirements are put forward for sixth generation (6G) wireless networks. To support massive ultra-reliable low-latency communications (mURLLC), in this paper we propose an adaptive finite blocklength framework to reduce over-the-air short packet transmissions with multiple-access delay-bounded demands. In particular, first give specified model. Then, reveal tradeoff relationship...

Orbital angular momentum (OAM) carried electromagnetic waves have the potential to improve spectrum efficiency in optical and radio-frequency communications due orthogonal wavefronts of different OAM modes. However, beams are vortically hollow divergent, which significantly decreases capacity transmissions. In addition, unaligned transceivers transmissions can result a high bit error rate (BER). The Talbot effect is self-imaging phenomenon that be used generate or with periodic repeating...

The extensive data interaction demands of an immersive metaverse necessitate the adoption emerging technologies to enable high-capacity communication. Vortex electromagnetic waves with different orbital angular momentum (OAM) modes are spatially orthogonal, providing a novel spatial multiplexing dimension achieve However, number orthogonal OAM based on discrete uniform circular array (UCA) is limited by elements in UCA, and traditional channel models unable accurately capture physical...

Magnetic induction (MI) communication, with stable channel conditions and small antenna size, is considered as a promising solution for underwater communication network. However, the narrowband nature of MI link can cause significant delays in To comprehensively ensure timeliness effectiveness network, this paper we introduce statistical quality service (QoS) framework aiming to maximize achievable rate while provisioning delay queue-length requirements. Specifically, employ effective...