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The burning of 5G sites across the UK in April 2020 has shocked the scientific and industrial society in the UK. The UK's mobile networks have reported 20 cases of masts being targeted in suspected arson attacks over the Easter weekend [1]. The attacks have been driven by conspiracy theories, which claim that the deployment of 5G networks has caused or helped accelerating the spread of COVID-19. But scientists say the connection between COVID-19 and 5G is a "complete nonsense" and biologically impossible. This article discusses the claims about 5G technology and its link to COVID-19 and will make a conclusion whether conspiracy theories have any ground. Our fact checking investigation lead to the conclusion that any claims connecting this technology to the pandemic are false. Inversely, the huge capabilities offered by 5G especially with IoT and AI that could be used to revolutionize the healthcare sector by providing better assistance to the frontline staff, and facilitating improved virus tracking, patient monitoring, data collection, and analysis.

We investigated the prevalence and clinical outcomes of COVID-19 in recipients of kidney transplants in the Bronx, New York, one of the epicenters of the pandemic. Between March 16 and June 2, 2020, 132 kidney transplant recipients tested positive by SARS-CoV-2 RT-PCR. From May 3 to July 29, 2020, 912 kidney transplant recipients were screened for SARS-CoV-2 IgG antibodies during routine clinic visits, of which 16.6% tested positive. Fifty-five of the 152 patients had previously tested positive by RT-PCR, while the remaining 97 did not have significant symptoms and had not been previously tested by RT-PCR. The prevalence of SARS-CoV-2 infection was 23.4% in the 975 patients tested by either RT-PCR or SARS-CoV-2 IgG. Older patients and patients with higher serum creatinine levels were more likely diagnosed by RT-PCR compared to SARS-CoV-2 IgG. Sixty-nine RT-PCR positive patients were screened for SARS-CoV-2 IgG antibodies at a median of 44 days post-diagnosis (Inter Quartile Range 31-58) and 80% were positive. Overall mortality was 20.5% but significantly higher (37.8% ) in the patients who required hospitalization. Twenty-three percent of the hospitalized patients required kidney replacement therapy and 6.3% lost their allografts. In multivariable analysis, older age, receipt of deceased-donor transplantation, lack of influenza vaccination in the previous year and higher serum interleukine-6 levels were associated with mortality. Thus, 42% of patients with a kidney transplant and with COVID-19 were diagnosed on antibody testing without significant clinical symptoms, 80% of patients with positive RT-PCR developed SARS-CoV-2 IgG and mortality was high among patients requiring hospitalization., Graphical abstract

In this work, the distributed base station (DBS) with remote radio head (RRH) is considered as the envisioned architecture of the fifth generation (5G) network. DBS network architecture supports easier scalability for network expansions using remote antennas in the form of RRHs. RRHs have been used in this work in order to compensate for the high path loss and penetration loss that characterise millimetre wave (mmWave) communications. The band of interest is the pioneer band at 26 GHz, which has been recently released for 5G services focused on areas of high traffic demand in the UK. DBS architecture can minimise the number of base stations required for the same quality of service (QoS). An algorithm has been developed for DBS scheduling. In addition to that, the gain of using DBS has been demonstrated in terms of: increasing the user data throughput, decreasing the unnecessary handovers as a result of dense network deployment, increasing the coverage probability in terms of line-of-sight (LoS) coverage, and minimising the impact of shadow fading. The results have shown significant improvement in terms of peak, average, and cell-edge data throughput, and the LoS coverage probability has been improved due to the spatial distribution of RRHs.

Background and objectives: In patients with kidney failure due to IgA nephropathy, IgA deposits can recur in a subsequent kidney transplant. The incidence, effect, and risk factors of IgA nephropathy recurrence is unclear, because most studies have been single center and sample sizes are relatively small.Design, setting, participants, & measurements: We performed a multicenter, international, retrospective study to determine the incidence, risk factors, and treatment response of recurrent IgA nephropathy after kidney transplantation. Data were collected from all consecutive patients with biopsy-proven IgA nephropathy transplanted between 2005 and 2015, across 16 “The Post-Transplant Glomerular Disease” study centers in Europe, North America, and South America.Results: Out of 504 transplant recipients with IgA nephropathy, recurrent IgA deposits were identified by kidney biopsy in 82 patients; cumulative incidence of recurrence was 23% at 15 years (95% confidence interval, 14 to 34). Multivariable Cox regression revealed a higher risk for recurrence of IgA deposits in patients with a pre-emptive kidney transplant (hazard ratio, 3.45; 95% confidence interval, 1.31 to 9.17) and in patients with preformed donorspecific antibodies (hazardratio, 2.59; 95%confidence interval, 1.09 to 6.19).Afterkidneytransplantation,development of de novo donor-specific antibodies was associated with subsequent higher risk of recurrence of IgA nephropathy (hazard ratio, 6.65; 95% confidence interval, 3.33 to 13.27). Immunosuppressive regimen was not associated with recurrent IgA nephropathy in multivariable analysis, including steroid use. Graft loss was higher in patients with recurrence of IgA nephropathy compared with patients without (hazard ratio, 3.69; 95% confidence interval, 2.04 to 6.66), resulting in 32% (95% confidence interval, 50 to 82) graft loss at 8 years after diagnosis of recurrence.Conclusions: In our international cohort, cumulative risk of IgA nephropathy recurrence increased after transplant and was associated with a 3.7-fold greater risk of graft loss.

The basic idea of this project is to support blind people in general and to support young people with blindness in particular, where the person will be able to walk comfortably with the use of this smart system. The smart system consists of gloves and shoes, which contain a set of sensors that will alert the user about the existence of any obstacle and also contains a GPS system, which will facilitate access to the person at time and in any emergency. This system will also help the person move and walk easily without using a walking stick.

Background Simultaneous pancreas and kidney transplantation (SPK) in the setting of end-stage renal disease offers unmatched outcomes in insulin dependent diabetic patients. Donor pool expansion through the transplantation of kidneys with acute kidney injury (AKI) is controversial. Methods 59 SPK transplants were classified by presence of donor AKI, defined as donor terminal creatinine ≥ 1.5x the initial creatinine or donor terminal creatinine > 4.0 mg/dL. Endpoints included graft and patient survival, delayed graft function (DGF), serum creatinine, glomerular filtration rate (GFR), Hemoglobin A1c (HbA1c) and acute rejection. Results The donor AKI group (n = 35) had significantly higher rates of DGF (38 v. 9%, p = 0.01). There was no difference in creatinine or GFR at 1, 3, 6 and 12 months. HbA1c was comparable at 3, 6 and 12 months. There was no significant difference in the percentage of patients that required anti-diabetic agents after transplant (14 v. 4%, p = 0.56). Conclusions We observed increased rates of DGF in SPK recipients with donor AKI. However, equivalent outcomes of pancreas and kidney function in both groups were observed.

In order to meet the huge growth in global mobile data traffic in 2020 and beyond, the development of the 5th Generation (5G) system is required as the current 4G system is expected to fall short of the provision needed for such growth. 5G is anticipated to use a higher carrier frequency in the millimetre wave (mm-wave) band, within the 20 to 90 GHz, due to the availability of a vast amount of unexploited bandwidth. It is a revolutionary step to use these bands because of their different propagation characteristics, severe atmospheric attenuation, and hardware constraints. In this paper, we carry out a survey of 5G research contributions and proposed design architectures based on mm-wave communications. We present and discuss the use of mm-wave as indoor and outdoor mobile access, as a wireless backhaul solution, and as a key enabler for higher order sectorisation. Wireless standards such as IEE802.11ad, which are operating in mm-wave band have been presented. These standards have been designed for short range, ultra high data throughput systems in the 60 GHz band. Furthermore, this survey provides new insights regarding relevant and open issues in adopting mm-wave for 5G networks. This includes increased handoff rate and interference in Ultra-Dense Network (UDN), waveform consideration with higher spectral efficiency, and supporting spatial multiplexing in mm-wave line of sight. This survey also introduces a distributed base station architecture in mm-wave as an approach to address increased handoff rate in UDN, and to provide an alternative way for network densification in a time and cost effective manner.

Cloud computing is considered as one of the key drivers for the next generation of mobile\ud networks (e.g. 5G). This is combined with the dramatic expansion in mobile networks, involving millions\ud (or even billions) of subscribers with a greater number of current and future mobile applications\ud (e.g. IoT). Cloud Radio Access Network (C-RAN) architecture has been proposed as a novel concept to\ud gain the benefits of cloud computing as an efficient computing resource, to meet the requirements of future\ud cellular networks. However, the computational complexity of obtaining the channel state information in\ud the full-centralized C-RAN increases as the size of the network is scaled up, as a result of enlargement in\ud channel information matrices. To tackle this problem of complexity and latency, MapReduce framework\ud and fast matrix algorithms are proposed. This paper presents two levels of complexity reduction in the\ud process of estimating the channel information in cellular networks. The results illustrate that complexity\ud can be minimized from O(N3) to O((N/k)3), where N is the total number of RRHs and k is the number of\ud RRHs per group, by dividing the processing of RRHs into parallel groups and harnessing the MapReduce\ud parallel algorithm in order to process them. The second approach reduces the computation complexity\ud from O((N/k)3) to O((N/k)2:807) using the algorithms of fast matrix inversion. The reduction in complexity\ud and latency leads to a significant improvement in both the estimation time and in the scalability of\ud C-RAN networks.

Cognitive radio networks (CRNs) are prone to emerging coexistence security threats such as primary user emulation attack (PUEA). Specifically, a malicious CRN may mimic licensees' [primary users (PUs)] signal characteristics to force another CRN to vacate its channels thinking that PUs have returned. While existing schemes are promising to some extent on detecting PUEAs, they are not able to prevent the attacks. In this article, the authors propose a PUEA deterrent (PUED) algorithm that can provide PUEAs' commission details: offender CRNs and attacks' time and bandwidth. There are many similarities between PUED and closed‐circuit television (CCTV) in terms of: deterrence strategy, reason for use, surveillance characteristics, surveillance outcome, and operation site. According to the criminology literature, robust CCTV systems have shown a significant reduction in visible offences (e.g. vehicle theft), reducing crime rates by 80%. Similarly, PUED will contribute the same effectiveness in deterring PUEAs. Furthermore, providing PUEAs' details will prevent the network's cognitive engine from considering the attacks as real PUs, consequently avoiding devising unreliable spectrum models for the attacked channels. Extensive simulations show the effectiveness of the PUED algorithm in terms of improving CRNs' performance.

Background and objectives FSGS recurrence after kidney transplantation is a major risk factor for graft loss. However, the natural history, clinical predictors, and response to treatment remain unclear because of small sample sizes and poor generalizability of single-center studies, and disease misclassification in registry-based studies. We therefore aimed to determine the incidence, predictors, and treatment response of recurrent FSGS in a large cohort of kidney transplant recipients. Design, setting, participants, & measurements The Post-Transplant Glomerular Disease (TANGO) project is an observational, multicenter, international cohort study that aims to investigate glomerular disease recurrence post-transplantation. Transplant recipients were screened for the diagnosis of idiopathic FSGS between 2005 and 2015 and details were recorded about the transplant, clinical outcomes, treatments, and other risk factors. Results Among 11,742 kidney transplant recipients screened for FSGS, 176 had a diagnosis of idiopathic FSGS and were included. FSGS recurred in 57 patients (32%; 95% confidence interval [95% CI], 25% to 39%) and 39% of them lost their graft over a median of 5 (interquartile range, 3.0–8.1) years. Multivariable Cox regression revealed a higher risk for recurrence with older age at native kidney disease onset (hazard ratio [HR], 1.37 per decade; 95% CI, 1.09 to 1.56). Other predictors were white race (HR, 2.14; 95% CI, 1.08 to 4.22), body mass index at transplant (HR, 0.89 per kg/m2; 95% CI, 0.83 to 0.95), and native kidney nephrectomies (HR, 2.76; 95% CI, 1.16 to 6.57). Plasmapheresis and rituximab were the most frequent treatments (81%). Partial or complete remission occurred in 57% of patients and was associated with better graft survival. Conclusions Idiopathic FSGS recurs post-transplant in one third of cases and is associated with a five-fold higher risk of graft loss. Response to treatment is associated with significantly better outcomes but is achieved in only half of the cases.

Background Kidney allocation system allows blood type B candidates accept kidneys from A2/A2B donors. There is no mandate by UNOS on which the anti-A2 level is acceptable. We aimed to investigate the safety of kidney transplant in blood group B patients with anti-A2 titers ≤16. Methods We performed 41 A2-incompatible kidney transplants in blood group B recipients between May 2015 and September 2019. Clinical outcomes were compared with a control group of 75 blood group B recipients who received blood group compatible kidney transplantation at the same period. Results Of the 41 recipients, 85% were male, 48% African American, with a median age of 53 (20-73) y. Thirty-eight (93%) were deceased-donor and 3 (7%) were living-donor kidney transplant recipients. Pretransplant anti-A2 IgG titers were 2 in 16, 4 in 9, 8 in 6, and 16 in 5 and too weak to titer in 5 recipients. Eight patients had pretransplant donor-specific antibodies. During a median follow-up of 32.6 mo (6-57.3) patient and graft survival were 100% and 92% in the A2-incompatible kidney transplant group, and 91% and 92% in the blood group compatible group, respectively. Twelve A2-incompatible recipients underwent a 21 clinically indicated kidney biopsies at a median 28 d (6-390) after transplantation. None of the patients developed acute antibody-mediated rejection and 2 patients (5%) had acute T-cell-mediated rejection. Interestingly, peritubular capillary C4d positivity was seen in 7 biopsies which did not have any findings of acute rejection or microvascular inflammation but not in any of the rejection-free biopsies in the control group. C4d positivity was persistent in 5 of those patients who had follow-up biopsies. Conclusions A2-incompatible transplantation is safe in patients with anti-A2 titers ≤16 with excellent short-term kidney allograft outcomes. C4d positivity is frequent in allograft biopsies without acute rejection.

Background. Patients undergoing kidney transplantation have increased risk of adverse cardiovascular events due to histories of hypertension, end-stage renal disease, and dialysis. As such, they are especially in need of accurate preoperative risk assessment. Methods. We compared three different risk assessment models for their ability to predict major adverse cardiac events at 30 days and 1 year after transplant. These were the PORT model, the RCRI model, and the Gupta model. We used a method based on generalized U-statistics to determine statistically significant improvements in the area under the receiver operator curve (AUC), based on a common major adverse cardiac event (MACE) definition. For the top-performing model, we added new covariates into multivariable logistic regression in an attempt to create further improvement in the AUC. Results. The AUCs for MACE at 30 days and 1 year were 0.645 and 0.650 (PORT), 0.633 and 0.661 (RCRI), and finally 0.489 and 0.557 (Gupta), respectively. The PORT model performed significantly better than the Gupta model at 1 year (p=0.039). When the sensitivity was set to 95%, PORT had a significantly higher specificity of 0.227 compared to RCRI’s 0.071 (p=0.009) and Gupta’s 0.08 (p=0.017). Our additional covariates increased the receiver operator curve from 0.664 to 0.703, but this did not reach statistical significance (p=0.278). Conclusions. Of the three calculators, PORT performed best when the sensitivity was set at a clinically relevant level. This is likely due to the unique variables the PORT model uses, which are specific to transplant patients.

Modern communication circuits use adaptive modulation techniques to fulfill its task. These techniques require changing the clock frequency of the of the communication units inside the communication circuit. The clock frequency can affect the power consumption of the digital circuits. In this paper, Dynamic Voltage / Frequency Scheduling (DVFS) is modified to use the clock frequency variation so that the CRC stage power is decreased. The DVFS is represented by a fuzzy controller that uses the frequency and the calculated power of the system as its input to calculate the required CRC unite supply voltage. The simulations show that for a 16bit CRC circuit a reduction in power in low frequencies can reach 75 % and the reduction is 4% in high frequencies.

To cope with massive growth over the past decade experienced by mobile network due to the popularity of smartphones and tablets, 5G networks are anticipated to use larger amounts of electromagnetic spectrum, spanning all the way from the microwave (sub 3GHz) to the millimetre wave (mmWave) bands (3–300 GHz). However, moving to the mmWave band will increase the exposure of users to high power/frequency radiation. This paper discusses the regulatory requirements at mmWave band. In this work, the performance of Cloud-Radio Access Network (C-RAN) network with uniformly distributed Remote Radio Heads (RRHs) was investigated and compared with default network architecture. This work provides insights on how to minimise the exposure to mmWave radiation in C-RAN network using Low-Power Nodes (LPN) by adopting Distributed Base Station (DBS) architecture. DBS can use remotely located low power antennas to extend the coverage of mmWave base stations. The results show that this architecture can significantly reduce the exposure to mmWave radiation without compromising the quality of service of C-RAN network, where the data throughput improvement is shown as the performance metric.

Inter Cell Interference (ICI) is a major challenge that degrades the performance of mobile systems, particularly\ud for cell-edge users. This problem arises significantly in the next generation system, as the trend of deployment is with high densification, which yields an ultra-dense network (UDN). One of the challenges in UDN is the dramatic increase of ICI from surrounding cells. A common technique to minimise ICI is interference coordination techniques. In this context, the most efficient ICI coordination is fractional frequency reuse (FFR).\ud This paper investigates the FFR in UDN millimetre wave\ud network at 26GHz band. The focus is on dense network with short inter site distance (ISD), and higher order sectorisation (HOS). The metrics used in frequency reuse is the signal to interference plus noise ratio (SINR) rather than the distance, as the line of sight in millimetre wave can be easily blocked by obstacles even if they are in close proximity to the serving base station. The work shows that FFR can improve the network performance in terms of per user cell-edge data throughput and average cell throughput, and maintain the peak data throughput\ud at a certain threshold. Furthermore, HOS has a potential gain over default sectored cells when the interference is carefully coordinated. The results show optimal values for bandwidth split per each scenario in FFR scheme to give the best trade-off between inner and outer zone users performance.

One of the challenges of Fifth Generation (5G) networks is how to support massive number of wireless devices in the Internet of Things (IoT). IoT will interconnect billions of devices under machine-to-machine communication links (M2M). However, this massive connectivity will create burden on the cellular network. Fixed sensors and wearable devices are expected to make the majority of future IoT traffic. And scheduling their huge traffic is the scope of this work. Sensors mobility has been considered with three speed, namely zero speed sensors (fixed), and medium and high speed of 30 and 100kmph, to simulate sensors in vehicles, and model the impact of vehicle mobility on the M2M links. This work defines the dimensionality in terms of the number of M2M devices that can be successfully connected, the required bandwidth, sensors mobility, and the transmission mode used. The mutual use of multi antennas, dense deployment of small cells, and the adoption of millimetre wave band, particularly in the 28GHz have been considered as the key enabling technologies to address the massive traffic generated by IoT. An algorithm has been set to schedule this type of traffic and to show whether the M2M devices completed their traffic upload or failed to reach the margin.

During the last decade, there has been a growing interest in developing automatic drilling process control solutions to increase drilling efficiency and consistency. But any drilling automation solution must be able to cope with drilling incidents as unexpected situations occur very frequently during the drilling process. Testing and verifying how drilling process control functions respond to drilling incidents on full scale rigs is both costly and risky, therefore it is tempting to perform such tests at a smaller scale where expenses and hazards are easier to manage. At the laboratory-scale, it is possible to reproduce many of the classical drilling problems, like torsional vibrations, forward and backward whirls, pack-offs, drill-pipe washouts, overpulls, buckling. However, the very small scale of the rig highlights specific technical challenges that are not usually relevant for full-scale drilling operations, while other demanding conditions associated with drilling wells over several kilometers, are absent at such a small scale. For that reason, the small scale of the autonomous drilling rig influences greatly the mechanical setup and its instrumentation, as the requirements for autonomy forces to cope, in a timely fashion, with extremely short reaction times. This paper describes the limits by which a small-scale rig should work and analyzes whether these restrictions are relevant for a standard drilling setup. The first part of the analysis focuses on how such small-scale rig experiments can be used to support the investigation of new real-time fault detection and model-based control algorithms and their associated instrumentation requirements, when the final objective is to improve full scale drilling automation. But thereafter, the study investigates how an autonomous small-scale rig can be used as a pedagogical tool for drilling engineering students. The comparison between the specific requirements of the small-scale laboratory setup with those of a standard drilling operations exacerbates the importance of scale when analyzing drilling automation solutions, as technical solutions that may look satisfactory for wells of normal dimensions may be inadequate for more extreme drilling conditions.

One challenge of wireless networks integration is to provide ubiquitous wireless access abilities and seamless handover for mobile communication devices between different types of technologies (3GPP and non-3GPP), such as Global System for Mobile Communication, Wireless Fidelity, Worldwide Interoperability for Microwave Access, Universal Mobile Telecommunications System and Long Term Evolution. This challenge is critical as mobile users are becoming increasingly demanding for services regardless of the technological complexities associated with them. To fulfil these requirements for seamless vertical handover (VHO) two main interworking frameworks have been proposed by IEEE Group and 3GPP for integration between the aforementioned technologies; namely, Media Independent Handover IEEE 802.21 and IP Multimedia Subsystem, where each of them requires mobility management protocol to complement its work, such as Mobile IP and Session Initiation Protocol, respectively. Various VHO approaches have been proposed in the literature based on these frameworks. In this paper, we survey the VHO approaches proposed in the literature and classify them into four categories based on these frameworks for which we present their objectives and performances issues.

Body Sensor Networks (BSNs) are mainly concerned with the human body. There are many restrictions concerning the sensor antenna design placed on/in the body due to harmful effects that may take place due to high power levels. Therefore, a dual-mode helical antenna resonating at the 2.4 GHz ISM band for medical application is proposed in this paper. The design includes two helices (normal and axial modes) acting as a single antenna with single feed. This combination gives the capability of serving both on-and off-body communication modes to enhance body coverage and reduce power consumption. The antenna is of a wide band from 2.2 GHz and extending beyond the 10 GHz of maximum gain of 9.67 dBi at the 2.45 GHz. The simulation results are obtained using the Ansoft HFSS software. Finally, another design of the dual-mode helix is presented using a dual-feed to give the flexibility of switching between communication modes (on-and off-body) as required.

Long Term Evolution Advanced (LTE-A) uses four different kinds of Cyclic Redundancy Check (CRC) to verify the integrity of the transmitted data, which implies using four circuits for each CRC in the transceiver system. In this paper, a novel algorithm is introduced to combine three of these CRC circuits into one in order to minimize the total area of the transceiver. This method will insure a considerable reduction in the dynamic power of the system. The new circuit is designed in a parallel fashion and is tested on an Altera FPGA platform to verify its power consumption and number of used gates hence, the total reduction in size. The result shows a good reduction in the number of used logic gates.

The radio spectrum is a finite resource and it is important that all users exploit it efficiently. Consequently, modulation schemes used for the wireless environment should utilize the RF channel bandwidth, and the transmitted power, as efficiently as possible. Across Europe, the digital video broadcasting (DVB) group has proposed a technique for a high data-rate return path known as DVB-return channel through terrestrial (DVB-RCT) specifically for consumer device convergence (full Internet connectivity through a television set). The introduction of adaptive M-ary quadrature amplitude modulation (MQAM) into the DVB-RCT standards as opposed to static modulation (as used in the DVB-terrestrial (DVB-T) standard) has enhanced the performance of bidirectional communication. In this paper, the impact of using diversity techniques in such systems is investigated. In specific, the gain, obtained from utilizing this combination of adaptive MQAM and diversity techniques in the system, is also shown.

Smart cities have recently become the mainstream approaches for urbanisation. Environmental, social and economic sustainability, digital inclusion and high quality of life are considered important elements in smart cities design. Emergency response system and resilience are among the most crucial dimensions of smart and future cities design due to the increase in various disruptions caused by frequent manmade and natural disasters such as September 2001 and Philippines Typhoon Haiyan 2013. Disasters cause great economic and human losses each year throughout the world. Transportations and Telecommunications play a crucial role in disaster response and management. Our research is focused on developing emergency response systems for disasters of various scales with a focus on transportation systems. We have proposed and evaluated a disaster management system that uses Intelligent Transportation Systems including Vehicular Ad hoc Networks (VANETs), mobile and Cloud Computing technologies. In this paper, we report our recent work on two major evacuation strategies, Demand Strategies (DS) and Speed Strategies (SS), which provide better evacuation results in smart cities settings.

One challenge of wireless networks integration is to provide ubiquitous wireless access abilities and seamless handover for mobile communication devices between different types of technologies (3GPP and non-3GPP) such as Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Long Term Evolution (LTE). This challenge is critical as Mobile Users (MUs) are becoming increasingly demanding for improved services regardless of the technological complexities associated with them. To fulfill these requirements for seamless Vertical Handover (VHO) two main interworking frameworks were proposed by IEEE Group and 3GPP for integration between the aforementioned technologies; namely, Media Independent Handover IEEE 802.21 (MIH) and IP Multimedia Subsystem (IMS), where each of them requires mobility management protocol to complement its work such as Mobile IP (MIP) and Session Initiation Protocol (SIP), respectively. In this paper, we overview these frameworks and show their components, benefits and drawbacks. Then we present our Imperative Alternative MIH for Vertical Handover (I AM 4 VHO) algorithm based on MIH framework and using fuzzy logic to provide low connection failure (probability of session rejection) and low signaling cost for enhancing VHO in heterogeneous wireless networks environment. Simulation based performance evaluation shows that the proposed algorithm reduces the probability of VHO connection failure by up to 75%.

In this paper, we address the problem of Vertical Handover (VHO) connection failure which occurs when a handover is initiated but a target network does not have sufficient resources to complete it. Thus it is important to identify Radio Access Technologies (RATs) list of priority for this purpose. We propose a new algorithm using fuzzy logic called Imperative Alternative Media Independent Handover for VHO (I AM 4 VHO), to provide low connection failure (probability of session rejection) for enhancing VHO in heterogeneous wireless networks environment. Finally, the calculation of the proposed algorithm shows that the probability of minimizing VHO connection failure is reduced.

The Capability of Relay Station deployment towards improving transmission data rates in the LTE-Advanced network has become widely accepted. However, Relay deployments are ususally burdened with the problem of resource allocation on the relay link where the relay station and users directly connected to the Donor eNB (DeNB) compete for available resources. In this paper, we propose a Collaborative Algorithm based on the Market Game theory to address this problem of Resource Allocation with LTE-Advanced Relay network. The result collated from our theoretical analysis indicates an improvement in the data rates achieved by users within the relay station's cell range.

One challenge of wireless networks integration is the ubiquitous wireless access abilities which provide the seamless handover for any moving communication device between different types of technologies (3GPP and non-3GPP) such as Global System for Mobile Communication (GSM), Wireless Fidelity (Wi-Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS) and Long Term Evolution (LTE). This challenge is important as Mobile Users (MUs) are becoming increasingly demanding for services regardless of technological complexities associated with it. To fulfill these requirements for seamless Vertical Handover (VHO) two main interworking architectures have been proposed by European Telecommunication Standards Institute (ETSI) for integration between different types of technologies; namely, loose and tight coupling. On the other hand, Media Independent Handover IEEE 802.21 (MIH) is a framework which has been proposed by IEEE Group to provide seamless VHO between the aforementioned technologies by utilizing these interworking architectures to facilitate and complement their works. The paper presents the design and the simulation of a Mobile IPv4 (MIPv4) based procedure for loose coupling architecture with MIH to optimize performance in heterogeneous wireless networks. The simulation results show that the proposed procedure provides seamless VHO with minimal latency and zero packet loss ratio.

n WiMAX mesh networks (WMN) the interferences among links have high effect on their performance. Therefore, an efficient routing algorithm is needed to choose the less interfered and more balanced links during the construction of the routing tree. Two Routing Tree Construction Algorithms, Paralleled (Par-RTCA) and Balanced-Paralleled (Bal-Par-RTCA) are introduced. The Bal-Par-RTCA, which is based on balancing the data and parallelizing the routes of the data from SS (Subscriber Station) to BS (Base Station), has the feature of Testing the Down-Node Group (TDNG). This feature increases the chance of conversion of Primary Interferences (PI) into Secondary Interferences (SI). The Modified Fair Relay Centralized Scheduling Algorithm (MFRCSA), which make use of spatial reuse efficiently, is also introduced here to avoid SI and increase concurrent transmissions over a certain time slot. As a result, system performance is enhanced in terms of Length of scheduling (L) and Links Concurrency Ratio (LCR). With spatial reuse and relative to the IEEE 802.16 standard Breadth First Tree (BFT) RTCA, the simulation results of the proposed Par-RTCA and Bal-Par-RTCA show LCR enhancement of 11.11% and 14.28%respectively.

Two mechanisms have been proposed independently by IEEE and 3GPP; namely, Media Independent\ud Handover (MIH) and Access Network Discovery and Selection Function (ANDSF), respectively. These\ud mechanisms enable a seamless Vertical Handover (VHO) between the different types of technologies\ud (3GPP and non-3GPP), such as GSM (Global System for Mobile Communication), Wireless Fidelity (Wi-\ud Fi), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications\ud System (UMTS) and Long Term Evolution (LTE). In this paper, we overview these mechanisms and show\ud their components, benefits and drawbacks. Then we present our Imperative Alternative MIH for Vertical\ud Handover (I AM 4 VHO) approach based on the approaches that have been studied in the literature with\ud better performance (packet loss and latency), less connection failure (probability of reject sessions), less\ud complexity and more exhaustive for enhancing VHO heterogeneous wireless networks environment.

In WCDMA 3rd Generation (3G) systems although there is no need for frequency planning as the case with second generation (2G) systems, the limitation of both capacity and coverage by the interference level in the system rendered the planning task for 3G systems far more complex than 2G systems. As the 3G radio networks now more sensitive to radio environment and traffic conditions, the advantage of dropping frequency planning could be cumbersome due to difficulties linked to what is called Cell-Breathing Phenomenon (CBP). In this work we propose a Dynamic WCDMA system that adjusts the spreading factor adaptively to overcome this problem. The simulation design will have the output of mapping the network load in terms of the number of users to the E b /N 0 required; this will give the network controller an idea about the number and type of users that may cause coverage to shrink i.e. start cell breathing. Therefore the network controller will be able to decide on the number and type of users admitted to the network at specific times.

In this paper, a predistortion neural network (PDNN) architecture has been imposed to the Sniffer Mobile Robot (SNFRbot) that is based on spatial multiplexed wireless Orthogonal Frequency Division Multiplexing (OFDM) transmission technology. This proposal is used to improve the system performance by combating one of the main drawbacks that is encountered by OFDM technology; Peak-to-Average Power Ratio (PAPR). Simulation results show that using PDNN resulted in better PAPR performance than the previously published work that is based on linear coding, such as Low Density Parity Check (LDPC) codes and turbo encoding whether using flat fading channel or a Doppler spread channel.

Airports are now amongst the most complex built environments known. Millions of people are using airports every year. However, providing adequate and reliable communication facilities to passengers and to other airport services represents a challenging issue. The Intelligent Airport (TINA) project aims to develop a new seamless wireless/wired ubiquitous infrastructure able to provide seamless integration at the service, network and physical layers. In this paper, we model the traffic and analyze the performance of the airport network through considering queuing networks. Spatial and temporal traffic variations were considered in a numerical example to show the performance of the model in terms of blocking probability. The model helps the network engineer and network operator to determine the location of cells with high traffic load and the time when the network becomes congested as well as the amount of network resources such as channels required to maintain balanced operation.

Fuelled by the phenomenal growth of vehicular and air traffic, motorways and airports are considered to be among the most dynamic environments known. Providing adequate and reliable communication facilities to motorway and airport users is extremely challenging due to the high variability of the environments in which they operate. Moreover, maintaining quality of service (QoS) for all traffic classes (voice, video and data) poses another problem due to their different delay characteristics. To overcome the challenges, in this paper we introduce the design of a medium access control (MAC) protocol namely Pico Cellular MAC (PC-MAC) for motorway and airport environments. For a motorway scenario, based on the analysis of real vehicular motorway traffic we develop our own vehicular simulator to study real-time vehicular traffic scenarios. For The INtelligent Airport (TINA) scenario, we study the airport layout in a cellular form and estimate the bandwidth required for multimedia users using our developed airport simulator.

As a result of increasing international air traffic, airports are one of the most complicated built environments. Airport terminals will increasingly require ubiquitous systems with high levels of computational power to provide the necessary intelligent automation, high quality services to passengers and stringent levels of safety and security that are as unobtrusive as possible. These requirements involve mobile appliances, and hence, an advanced telecommunication network that can handle the teletraffic load reliably and efficiently. In this paper we propose a mixed of series queues to model the airport network. The model cannot result in closed form solution to the steady state probability of the network. Instead, the proposed model divides the whole network into stages of separately defined queues which can be dealt with independently. Important data such as number of passengers in the nodes and the time spent in the queues can be obtained by considering each stage separately. The model is used to find the teletraffic distribution over the network in different times.

This work deals with the performance of a Sniffer Mobile Robot (SNFRbot)-based spatial multiplexed wireless Orthogonal Frequency Division Multiplexing (OFDM) transmission technology. The use of Multi-Input Multi-Output (MIMO)-OFDM technology increases the wireless transmission rate without increasing transmission power or bandwidth. A generic multilayer architecture of the SNFRbot is proposed with low power and low cost. Some experimental results are presented and show the efficiency of sniffing deadly gazes, sensing high temperatures and sending live videos of the monitored situation. Moreover, simulation results show the achieved performance by tackling the Peak-to-Average Power Ratio (PAPR) problem of the used technology using Low Density Parity Check (LDPC) codes; and the effect of combating the PAPR on the bit error rate (BER) and the signal to noise ratio (SNR) over a Doppler spread channel.

In third generation (3G) wireless systems we have a number of resources being used exclusively and simultaneously to satisfy the requirements of an arriving multimedia call. This would require the occupation and release of these resources to be in a manageable fashion. In this paper, we discuss a multi-component teleservice model for multimedia applications. Subsequently, based on this teleservice model, we introduce and analyse a multi-component based resource allocation scheme (MC-RAS) for call and traffic management that exploits the multi-component nature of multimedia traffic. Practical network parameters were used to evaluate the performance of the scheme as compared with the standard approach based on the single multimedia stream flow. The proposed scheme shows better performance in terms of reducing blocking probabilities.

In third generation (3G) wireless systems we have a number of resources being used exclusively and simultaneously to satisfy the requirements of an arriving subscriber. This would require the occupation and release of these resources to be in a manageable fashion. In this article, we have proposed an analytical model for resource allocation to investigate the performance of a multimedia mobile network in terms of call blocking probability. Our model is unlike conventional channel allocation schemes as it assigns resources from each class of services supported by the system to a single subscriber call.

Hierarchical cell structure (HCS) has become a major trend in the design of 3G systems networks in order to support the high capacity demand required for multimedia traffic in 3G systems. In this type of network an efficient cell assignment scheme is required to improve the quality of service (QoS) of the system in terms of dropping probability, blocking probability, and channel utilisation. In this paper we propose a new channel assignment scheme which exploits the delay insensitive property of the non real-time data service to admit users to the preferred cell layer. We believe the new scheme is anticipated to improve the QoS of the realtime voice users for both blocking probability and channel utilisation parameters.

The performance of time division multiple access (TDMA) is affected by various factors. Accurate coverage prediction, modulation and coverage control techniques can significantly improve the capacity. Spectrum efficiency and good coverage are the main objectives of radio system planning. The capacity of a cellular system is directly related to spectrum efficiency and is directly proportional to the cluster size, so that any decrease in the size indicates that co-channel cells are located much closer together. This allows more frequency channels to be reused taking into account minimum co-channel interference (CCI). The above factors have an impact on the capacity, it is therefore crucial to include them in the evaluation to minimize the assumptions made. This paper shows development of a model, which includes these factors, to accurately estimate the system capacity. This paper is related directly to Al-Akaidi et al. (2001).

In this paper, a new Adaptive Centralised Location-Service (ACLS) routing protocol is presented, which tracks mobile node locations and recover the side effects of nodes mobility. In ACLS, some nodes consider themselves as servers serve other nodes according to their location and status in the network. The transmission is achieved by 'anonymous addressing' technique where the receivers decide on their own, whether they are the intended destination. Results indicate very good and impressive performance of the ACLS in terms of scalability with the number of nodes, speed and location update success rate.

The development of airports such as the recently inaugurated Heathrow Terminal 5, as well as the increasing number of people using these facilities every day for business reasons or just for pleasure, reveals the importance of adequate and reliable communication facilities in this context. This environment is characterized by multiservice, multistandard wireless technologies and a highly variable traffic demand in space and time due to passenger flow, behavior, and usage from the terminal's entrance to the corresponding boarding gate, ruled by flight departure schedules, in the indoor environment. The Intelligent Airport (TINA) project establishes its objective as the creation of a seamless hybrid wireless and wired infrastructure capable of providing users with a wide range of services, based on radio-over-fiber (RoF) networks, anticipating the deployment of multiple air interfaces within 4G networks. In this paper the spatial and temporal traffic demand is analyzed and modeled through simulation, as a means of selecting the optimum location for the base stations/antenna units (BSs/AUs) in the network. A load-balancing technique is applied to ease the load on congested cells using strategically located fixed relay nodes, and the network's behavior is analyzed for different BS properties.

Convolutional coding has been classically used in channel coding to provide Forward Error Correction (FEC) capability to the system by adding some carefully designed redundant information to the data being transmitted through the channel. However, in this work, we use convolutional codes for a different purpose: the reduction of the Peak-to-Average Power Ratio (PAPR) in an Orthogonal Frequency Division Multiplexing (OFDM) system by utilising these codes as spreading codes. This is an alternative to turbo coding and Low-Density Parity Check (LDPC) codes, which have been used for the same purpose in our previous works. The PAPR is a major drawback in most multicarrier communication techniques such as OFDM. OFDM consists of lots of independent modulated subcarriers; as a result, the amplitude of such a signal can have very large values. These large peaks increase the amount of intermodulation distortion, resulting in an increase in the error rate. The PAPR of an OFDM signal can be reduced in several ways: Selective Mapping (SLM), Golay sequences, cyclic coding, clipping and filtering and multiple signal representation techniques. Our results show that using LDPC coding in mitigating PAPR led to a 6%-60% reduction in this ratio, which is better than our proposed work based on either turbo coding or convolutional coding and the SLM and clipping techniques in the literature.

Quality of Service (QoS) optimisation of converged networks has become an absolute necessity for mobile communication businesses to deliver business differentiation in a saturated market. In this paper, we present a resource allocation scheme for 3G wireless systems that optimises QoS control by exploiting multi-component nature of multimedia applications. We build a Markovian model of our Multi-Component Resource Allocation Scheme (MCRAS) and analyse its performance by computing steady-state probability distributions. We compute blocking probability – the key QoS parameter – for different system configurations using MCRAS and make comparisons with Complete Partitioning (CP) and Complete Sharing (CSH) resource allocation schemes.

In this paper, we propose and evaluate an adaptive resource allocation scheme for Wideband Code Division Multiple Access multimedia systems. We give a discussion on the inherently multi-component nature of multimedia applications for wireless communication systems, and describe our multi-component model. Subsequently, we introduce our adaptive resource allocation scheme based on the described teleservice model. The multimedia traffic and the adaptive scheme are modelled and analysed next, using queuing theory. The scheme is evaluated and compared against the conventional schemes, namely, the Non-Priority scheme and the Guard Channel scheme, using performance results for blocking and dropping probability. We demonstrate that the proposed scheme is more flexible and efficient in guaranteeing Quality of Service than the conventional schemes.

In this paper, we propose a multi-component teleservice model for multimedia applications. A Novel Resource Allocation Scheme for call and traffic management that exploits the multi-component teleservice is developed and analysed. The scheme was applied to hierarchical cellular structure networks. The performance is compared with the standard approach based on the single multimedia stream flow. The proposed scheme shows better performance in terms of reducing blocking and dropping probabilities.

Hierarchical Cell Structure (HCS) has become a major trend in the design of Third Generation (3G) system networks in order to support the high capacity demand required for multimedia traffic in 3G systems. In this type of network, an efficient call admission scheme is required to improve the Quality of Service (QoS) of the system in terms of dropping probability, blocking probability, and channel utilisation. This paper proposed and analysed a call admission scheme for supporting both voice and data traffic in HCS that uses both guard channels and queuing to handle the communication traffic in the system shows improvement in the performance of the system when a guard channel used.

With the coming about of the 3rd Generation (3G) systems, Universal Mobile Telecommunications System (UMTS) technology, so came with it 'cell breathing'. This phenomenon is directly linked to the codependent of capacity and coverage. The greater the level of influx of users within the cell, the higher the interference and hence the lower the cell coverage becomes. This dynamic behaviour makes network planning and optimisation a complex task. Our paper proposes a power control algorithm to guarantee services for the area of a cell as the load increases. The proposed algorithm reduces the power transmitted from active users for each iteration of the algorithm. This will enable the system to have constant cell coverage. The performance of the proposed algorithm is compared with the traditional power control scheme that tends to increase the power of the users as the load increases to retrieve the target Signal-to-Interference Ratio (SIR).

The September 2001 attacks and the 2011 Japan earthquake and tsunami disaster are examples of manmade and natural disasters which have revealed the importance of having a disaster management system in place. A great deal of advisory and policy documents need to be developed by various government authorities. The Intelligent Transportation Systems and Services (ITSS) are set to play a crucial role in responding to emergencies and large-scale disasters.\ud \ud In previous works, we have proposed and evaluated an intelligent disaster management system based on the emerging ICT technologies such as Vehicular Ad hoc Networks (VANETs) and Cloud Computing with a focus on transportation in urban environments. Also, we have developed a tool to examine previous proposed intelligent system performance in improving the transportation evacuation strategies, and Demand Strategy (DS) has been shown as one of the various evacuation strategies to measure the improvements. In this paper, we applied and evaluated another transportation evacuation strategy called Speed Strategy (SS), independently for traffic network. In addition, the driver response to the emergency situations and their behaviors in travel choices may be difficult to quantify theoretically, however, driver response to evacuation pre-plans is part of the tool design and we present the importance of this factor through various evacuation strategies.

In this paper, we propose a call admission control scheme for supporting voice and data traffic in hierarchical cell structured networks (HCS). The proposed scheme guarantees to satisfy the required quality of service for both traffic types in accordance with their characteristics, such as mobility and delay constraints. In the proposed scheme, slow and fast voice traffic are allowed to overflow from one layer to another in the case of shortage of resources in the preferred layer. Due to their high bit rate, data traffic are not allowed to overflow between layers, therefore data traffic would stay in the originating layer. However, a buffer is available in each cell to serve handoff data traffic. The proposed scheme is analysed using a multi-dimensional Markov chain, and QoS measurement parameters are derived. Analytical results show significant improvements in terms of the blocking and dropping probability.