10–50 m
MmWave is a very high band spectrum between 30 to 300 GHz. As it is a significantly less used spectrum, it provides very high-speed wireless communication. MmWave offers ultra-wide bandwidth for next-generation mobile networks. MmWave has lots of advantages, but it has some disadvantages, too, such as mmWave signals are very high-frequency signals, so they have more collision with obstacles in the air which cause the signals loses energy quickly. Buildings and trees also block MmWave signals, so these signals cover a shorter distance. To resolve these issues, multiple small cell stations are installed to cover the gap between end-user and base station [ 18 ]. Small cell covers a very shorter range, so the installation of a small cell depends on the population of a particular area. Generally, in a populated place, the distance between each small cell varies from 10 to 90 meters. In the survey [ 20 ], various authors implemented small cells with massive MIMO simultaneously. They also reviewed multiple technologies used in 5G like beamforming, small cell, massive MIMO, NOMA, device to device (D2D) communication. Various problems like interference management, spectral efficiency, resource management, energy efficiency, and backhauling are discussed. The author also gave a detailed presentation of all the issues occurring while implementing small cells with various 5G technologies. As shown in the Figure 7 , mmWave has a higher range, so it can be easily blocked by the obstacles as shown in Figure 7 a. This is one of the key concerns of millimeter-wave signal transmission. To solve this issue, the small cell can be placed at a short distance to transmit the signals easily, as shown in Figure 7 b.
Pictorial representation of communication with and without small cells.
Beamforming is a key technology of wireless networks which transmits the signals in a directional manner. 5G beamforming making a strong wireless connection toward a receiving end. In conventional systems when small cells are not using beamforming, moving signals to particular areas is quite difficult. Beamforming counter this issue using beamforming small cells are able to transmit the signals in particular direction towards a device like mobile phone, laptops, autonomous vehicle and IoT devices. Beamforming is improving the efficiency and saves the energy of the 5G network. Beamforming is broadly divided into three categories: Digital beamforming, analog beamforming and hybrid beamforming. Digital beamforming: multiuser MIMO is equal to digital beamforming which is mainly used in LTE Advanced Pro and in 5G NR. In digital beamforming the same frequency or time resources can be used to transmit the data to multiple users at the same time which improves the cell capacity of wireless networks. Analog Beamforming: In mmWave frequency range 5G NR analog beamforming is a very important approach which improves the coverage. In digital beamforming there are chances of high pathloss in mmWave as only one beam per set of antenna is formed. While the analog beamforming saves high pathloss in mmWave. Hybrid beamforming: hybrid beamforming is a combination of both analog beamforming and digital beamforming. In the implementation of MmWave in 5G network hybrid beamforming will be used [ 84 ].
Wireless signals in the 4G network are spreading in large areas, and nature is not Omnidirectional. Thus, energy depletes rapidly, and users who are accessing these signals also face interference problems. The beamforming technique is used in the 5G network to resolve this issue. In beamforming signals are directional. They move like a laser beam from the base station to the user, so signals seem to be traveling in an invisible cable. Beamforming helps achieve a faster data rate; as the signals are directional, it leads to less energy consumption and less interference. In [ 21 ], investigators evolve some techniques which reduce interference and increase system efficiency of the 5G mobile network. In this survey article, the authors covered various challenges faced while designing an optimized beamforming algorithm. Mainly focused on different design parameters such as performance evaluation and power consumption. In addition, they also described various issues related to beamforming like CSI, computation complexity, and antenna correlation. They also covered various research to cover how beamforming helps implement MIMO in next-generation mobile networks [ 85 ]. Figure 8 shows the pictorial representation of communication with and without using beamforming.
Pictorial Representation of communication with and without using beamforming.
Mobile Edge Computing (MEC) [ 24 ]: MEC is an extended version of cloud computing that brings cloud resources closer to the end-user. When we talk about computing, the very first thing that comes to our mind is cloud computing. Cloud computing is a very famous technology that offers many services to end-user. Still, cloud computing has many drawbacks. The services available in the cloud are too far from end-users that create latency, and cloud user needs to download the complete application before use, which also increases the burden to the device [ 86 ]. MEC creates an edge between the end-user and cloud server, bringing cloud computing closer to the end-user. Now, all the services, namely, video conferencing, virtual software, etc., are offered by this edge that improves cloud computing performance. Another essential feature of MEC is that the application is split into two parts, which, first one is available at cloud server, and the second is at the user’s device. Therefore, the user need not download the complete application on his device that increases the performance of the end user’s device. Furthermore, MEC provides cloud services at very low latency and less bandwidth. In [ 23 , 87 ], the author’s investigation proved that successful deployment of MEC in 5G network increases the overall performance of 5G architecture. Graphical differentiation between cloud computing and mobile edge computing is presented in Figure 9 .
Pictorial representation of cloud computing vs. mobile edge computing.
Security is the key feature in the telecommunication network industry, which is necessary at various layers, to handle 5G network security in applications such as IoT, Digital forensics, IDS and many more [ 88 , 89 ]. The authors [ 90 ], discussed the background of 5G and its security concerns, challenges and future directions. The author also introduced the blockchain technology that can be incorporated with the IoT to overcome the challenges in IoT. The paper aims to create a security framework which can be incorporated with the LTE advanced network, and effective in terms of cost, deployment and QoS. In [ 91 ], author surveyed various form of attacks, the security challenges, security solutions with respect to the affected technology such as SDN, Network function virtualization (NFV), Mobile Clouds and MEC, and security standardizations of 5G, i.e., 3GPP, 5GPPP, Internet Engineering Task Force (IETF), Next Generation Mobile Networks (NGMN), European Telecommunications Standards Institute (ETSI). In [ 92 ], author elaborated various technological aspects, security issues and their existing solutions and also mentioned the new emerging technological paradigms for 5G security such as blockchain, quantum cryptography, AI, SDN, CPS, MEC, D2D. The author aims to create new security frameworks for 5G for further use of this technology in development of smart cities, transportation and healthcare. In [ 93 ], author analyzed the threats and dark threat, security aspects concerned with SDN and NFV, also their Commercial & Industrial Security Corporation (CISCO) 5G vision and new security innovations with respect to the new evolving architectures of 5G [ 94 ].
AuthenticationThe identification of the user in any network is made with the help of authentication. The different mobile network generations from 1G to 5G have used multiple techniques for user authentication. 5G utilizes the 5G Authentication and Key Agreement (AKA) authentication method, which shares a cryptographic key between user equipment (UE) and its home network and establishes a mutual authentication process between the both [ 95 ].
Access Control To restrict the accessibility in the network, 5G supports access control mechanisms to provide a secure and safe environment to the users and is controlled by network providers. 5G uses simple public key infrastructure (PKI) certificates for authenticating access in the 5G network. PKI put forward a secure and dynamic environment for the 5G network. The simple PKI technique provides flexibility to the 5G network; it can scale up and scale down as per the user traffic in the network [ 96 , 97 ].
Communication Security 5G deals to provide high data bandwidth, low latency, and better signal coverage. Therefore secure communication is the key concern in the 5G network. UE, mobile operators, core network, and access networks are the main focal point for the attackers in 5G communication. Some of the common attacks in communication at various segments are Botnet, message insertion, micro-cell, distributed denial of service (DDoS), and transport layer security (TLS)/secure sockets layer (SSL) attacks [ 98 , 99 ].
Encryption The confidentiality of the user and the network is done using encryption techniques. As 5G offers multiple services, end-to-end (E2E) encryption is the most suitable technique applied over various segments in the 5G network. Encryption forbids unauthorized access to the network and maintains the data privacy of the user. To encrypt the radio traffic at Packet Data Convergence Protocol (PDCP) layer, three 128-bits keys are applied at the user plane, nonaccess stratum (NAS), and access stratum (AS) [ 100 ].
In this section, various issues addressed by investigators in 5G technologies are presented in Table 13 . In addition, different parameters are considered, such as throughput, latency, energy efficiency, data rate, spectral efficiency, fairness & computing capacity, transmission rate, coverage, cost, security requirement, performance, QoS, power optimization, etc., indexed from R1 to R14.
Summary of 5G Technology above stated challenges (R1:Throughput, R2:Latency, R3:Energy Efficiency, R4:Data Rate, R5:Spectral efficiency, R6:Fairness & Computing Capacity, R7:Transmission Rate, R8:Coverage, R9:Cost, R10:Security requirement, R11:Performance, R12:Quality of Services (QoS), R13:Power Optimization).
Approach | R1 | R2 | R3 | R4 | R5 | R6 | R7 | R8 | R9 | R10 | R11 | R12 | R13 | R14 |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Panzner et al. [ ] | Good | Low | Good | - | Avg | - | - | - | - | - | - | - | - | - |
Qiao et al. [ ] | - | - | - | - | - | - | - | Avg | Good | Avg | - | - | - | - |
He et al. [ ] | Avg | Low | Avg | - | - | - | - | - | - | - | - | - | - | - |
Abrol and jha [ ] | - | - | Good | - | - | - | - | - | - | - | - | - | - | Good |
Al-Imari et al. [ ] | - | - | - | - | Good | Good | Avg | - | - | - | - | - | - | - |
Papadopoulos et al. [ ] | Good | Low | Avg | - | Avg | - | - | - | - | - | - | - | - | - |
Kiani and Nsari [ ] | - | - | - | - | Avg | Good | Good | - | - | - | - | - | - | - |
Beck [ ] | - | Low | - | - | - | - | - | Avg | - | - | - | Good | - | Avg |
Ni et al. [ ] | - | - | - | Good | - | - | - | - | - | - | Avg | Avg | - | - |
Elijah [ ] | Avg | Low | Avg | - | - | - | - | - | - | - | - | - | - | - |
Alawe et al. [ ] | - | Low | Good | - | - | - | - | - | - | - | - | - | Avg | - |
Zhou et al. [ ] | Avg | - | Good | - | Avg | - | - | - | - | - | - | - | - | - |
Islam et al. [ ] | - | - | - | - | Good | Avg | Avg | - | - | - | - | - | - | - |
Bega et al. [ ] | - | Avg | - | - | - | - | - | - | - | - | - | - | Good | - |
Akpakwu et al. [ ] | - | - | - | Good | - | - | - | - | - | - | Avg | Good | - | - |
Wei et al. [ ] | - | - | - | - | - | - | - | Good | Avg | Low | - | - | - | - |
Khurpade et al. [ ] | - | - | - | Avg | - | - | - | - | - | - | - | Avg | - | - |
Timotheou and Krikidis [ ] | - | - | - | - | Good | Good | Avg | - | - | - | - | - | - | - |
Wang [ ] | Avg | Low | Avg | Avg | - | - | - | - | - | - | - | - | - | - |
Akhil Gupta & R. K. Jha [ ] | - | - | Good | Avg | Good | - | - | - | - | - | - | Good | Good | - |
Pérez-Romero et al. [ ] | - | - | Avg | - | - | - | - | - | - | - | - | - | - | Avg |
Pi [ ] | - | - | - | - | - | - | - | Good | Good | Avg | - | - | - | - |
Zi et al. [ ] | - | Avg | Good | - | - | - | - | - | - | - | - | - | - | - |
Chin [ ] | - | - | Good | Avg | - | - | - | - | - | Avg | - | Good | - | - |
Mamta Agiwal [ ] | - | Avg | - | Good | - | - | - | - | - | - | Good | Avg | - | - |
Ramesh et al. [ ] | Good | Avg | Good | - | Good | - | - | - | - | - | - | - | - | - |
Niu [ ] | - | - | - | - | - | - | - | Good | Avg | Avg | - | - | - | |
Fang et al. [ ] | - | Avg | Good | - | - | - | - | - | - | - | - | - | Good | - |
Hoydis [ ] | - | - | Good | - | Good | - | - | - | - | Avg | - | Good | - | - |
Wei et al. [ ] | - | - | - | - | Good | Avg | Good | - | - | - | - | - | - | - |
Hong et al. [ ] | - | - | - | - | - | - | - | - | Avg | Avg | Low | - | - | - |
Rashid [ ] | - | - | - | Good | - | - | - | Good | - | - | - | Avg | - | Good |
Prasad et al. [ ] | Good | - | Good | - | Avg | - | - | - | - | - | - | - | - | - |
Lähetkangas et al. [ ] | - | Low | Av | - | - | - | - | - | - | - | - | - | - | - |
This survey article illustrates the emergence of 5G, its evolution from 1G to 5G mobile network, applications, different research groups, their work, and the key features of 5G. It is not just a mobile broadband network, different from all the previous mobile network generations; it offers services like IoT, V2X, and Industry 4.0. This paper covers a detailed survey from multiple authors on different technologies in 5G, such as massive MIMO, Non-Orthogonal Multiple Access (NOMA), millimeter wave, small cell, MEC (Mobile Edge Computing), beamforming, optimization, and machine learning in 5G. After each section, a tabular comparison covers all the state-of-the-research held in these technologies. This survey also shows the importance of these newly added technologies and building a flexible, scalable, and reliable 5G network.
This article covers a detailed survey on the 5G mobile network and its features. These features make 5G more reliable, scalable, efficient at affordable rates. As discussed in the above sections, numerous technical challenges originate while implementing those features or providing services over a 5G mobile network. So, for future research directions, the research community can overcome these challenges while implementing these technologies (MIMO, NOMA, small cell, mmWave, beam-forming, MEC) over a 5G network. 5G communication will bring new improvements over the existing systems. Still, the current solutions cannot fulfill the autonomous system and future intelligence engineering requirements after a decade. There is no matter of discussion that 5G will provide better QoS and new features than 4G. But there is always room for improvement as the considerable growth of centralized data and autonomous industry 5G wireless networks will not be capable of fulfilling their demands in the future. So, we need to move on new wireless network technology that is named 6G. 6G wireless network will bring new heights in mobile generations, as it includes (i) massive human-to-machine communication, (ii) ubiquitous connectivity between the local device and cloud server, (iii) creation of data fusion technology for various mixed reality experiences and multiverps maps. (iv) Focus on sensing and actuation to control the network of the entire world. The 6G mobile network will offer new services with some other technologies; these services are 3D mapping, reality devices, smart homes, smart wearable, autonomous vehicles, artificial intelligence, and sense. It is expected that 6G will provide ultra-long-range communication with a very low latency of 1 ms. The per-user bit rate in a 6G wireless network will be approximately 1 Tbps, and it will also provide wireless communication, which is 1000 times faster than 5G networks.
Author contributions.
Conceptualization: R.D., I.Y., G.C., P.L. data gathering: R.D., G.C., P.L, I.Y. funding acquisition: I.Y. investigation: I.Y., G.C., G.P. methodology: R.D., I.Y., G.C., P.L., G.P., survey: I.Y., G.C., P.L, G.P., R.D. supervision: G.C., I.Y., G.P. validation: I.Y., G.P. visualization: R.D., I.Y., G.C., P.L. writing, original draft: R.D., I.Y., G.C., P.L., G.P. writing, review, and editing: I.Y., G.C., G.P. All authors have read and agreed to the published version of the manuscript.
This paper was supported by Soonchunhyang University.
Informed consent statement, data availability statement, conflicts of interest.
The authors declare no conflict of interest.
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Scientific Reports volume 11 , Article number: 636 ( 2021 ) Cite this article
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5G has been designed for blazing fast and low-latency communications. To do so, mm-wave frequencies were adopted and allowed unprecedently high radiated power densities by the FCC. Unknowingly, the architects of 5G have, thereby, created a wireless power grid capable of powering devices at ranges far exceeding the capabilities of any existing technologies. However, this potential could only be realized if a fundamental trade-off in wireless energy harvesting could be circumvented. Here, we propose a solution that breaks the usual paradigm, imprisoned in the trade-off between rectenna angular coverage and turn-on sensitivity. The concept relies on the implementation of a Rotman lens between the antennas and the rectifiers. The printed, flexible mm-wave lens allows robust and bending-resilient operation over more than 20 GHz of gain and angular bandwidths. Antenna sub-arrays, rectifiers and DC combiners are then added to the structure to demonstrate its combination of large angular coverage and turn-on sensitivity—in both planar and bent conditions—and a harvesting ability up to a distance of 2.83 m in its current configuration and exceeding 180 m using state-of-the-art rectifiers enabling the harvesting of several μW of DC power (around 6 μW at 180 m with 75 dBm EIRP).
Introduction.
Our era is witnessing a rapid development in the field of millimeter-wave (mm-wave) and Internet of Things (IoT) technologies with a projected 40 billion IoT devices to be installed by 2025 1 . This could result in a huge number of batteries needing to be continuously charged and replaced. The design and realization of energy-autonomous, self-powered systems: the perpetual IoT, is therefore highly desirable. One potential way of satisfying these goals is through electromagnetic energy harvesting. A powerful source for electromagnetic scavenging is mm-wave energy, present in the fifth-generation (5G) of mobile communications bands (above 24 GHz), where the limits of allowable transmitted Effective Isotropic Radiated Power (EIRP) by the Federal Communications Commission (FCC) regulations are pushed beyond (reaches 75 dBm) that of their lower-frequency counterparts. Following the path loss model defined by the 3rd Generation Partnership Project Technical Report 3GPP TR 38.901 (release 16) in outdoor Urban Macro Line of Sight conditions (UMa LOS), the power density expected to be received at 28 GHz for a transmitted power of 75 dBm EIRP is 28 μW cm −2 at a distance of 100 m away from the transmitter. This demonstrates the ability of 5G to create a usable network of wireless power. In addition to the advantage of high transmitted power available at 5G, moving to mm-wave bands allows the realization of modular antennas arrays instead of single elements, thereby allowing a fine scaling of their antenna aperture, which can more than compensate for the high path loss at these frequencies through the addition of extremely-large gains 2 . However, one limitation accompanies large gain antennas: their inability to provide a large angular coverage. As the relative orientations of the sources and harvesters are generally unknown, the use of large aperture mm-wave harvesters may seem limiting and impossible. Individual rectennas, constituted of small antenna elements, can realistically be DC combined. However, this approach does not increase the turn-on sensitivity (lowest turn-on power) of the overall rectenna system: RF combination is needed.
Beamforming networks (BFNs) are used to effectively create simultaneous beam angular coverage with large-gain arrays, by mapping a set of directions to a set of feeding ports. An important class of these multiple networks is the microwave passive BFN that has been widely used in switched-beam antenna systems and applications. Hybrid combination techniques, based on Butler matrix networks, have been used in previous works for energy harvesting at lower frequencies 3 , 4 ,—more specifically at 2.45 GHz—to achieve wider angular coverage harvesting. However, these Ultra-High Frequency (UHF) arrays are impractically large for IoT applications and the implementation of their Butler matrices at higher frequencies would necessitate costly high-resolution fabrication. While sub-optimal—because of its large size—in the UHF band, the Rotman lens becomes the BFN of choice in the realm of mm-wave energy harvesting. Compared to their lower frequencies counterpart, fewer implementations are presented in the literature targeting energy harvesting at higher frequencies, more specifically 24 GHz and above. However, these systems later displayed in the table of comparison 5 , 6 , 7 , suffer from a narrow angular coverage.
In this paper, the authors demonstrate a full implementation of an entirely flexible, bending-resilient and simultaneously high gain and large angular coverage system for 5G/mm-wave energy harvesting based on a Rotman lens. For IoT applications, there is a benefit to making extremely low-profile devices that can conformally fit onto any surface in the environment such as walls, bodies, vehicles, etc. Therefore, thanks to the use of mm-waves, antennas with such features can be readily designed and fabricated. A Rotman lens-based rectenna has been first proposed in 8 , where a preliminary prototype and approach were presented, resulting in a quasi-flexible system, 80° angular coverage and 21-fold increase in the harvested power compared to a non-Rotman-based system. Here, the previously-predicted potential of 5G-powered nodes for the IoT and long-range passive mm-wave Radio Frequency IDentification (RFID) devices, is further taken advantage of, and effectively demonstrated. In order to do so, a thorough analysis of the lens itself—a structure that was not revealed in 8 —is first presented, exposing its key design parameters and resulting measured broadband behavior tested in both planar and bent conditions over more than 20 GHz of bandwidth. In addition, a scalability study of the approach, outlining the optimal size of such a system is reported, thereby proving the extent of the capability of providing a combination of good array factor and wide beam coverage. The novelty of this system also lies in the realization of a fully-flexible 28 GHz Rotman-lens-based rectenna system, completed by the design of a new DC combiner on a flexible 125 μm-thin polyimide Kapton substrate. The new DC combiner uses a reduced number of bypass diodes and increases the angular coverage of the system by more than 30% compared to 8 . Furthermore, the frequency-broadband behavior enabled by the use of the Rotman lens makes the full rectenna system bending-resilient, a property now demonstrated through its characterizations in flexing and conformally-mounted configurations. Finally, the system’s potential for long-range mm-wave harvesting is expressed for the first time, by reporting an unprecedented harvesting range of 2.83 m.
Rotman lens scalability study for harvesting applications.
The Rotman lens, introduced in the 1960s, constitutes one of the most common and cost-effective designs for BFNs and is commonly utilized to enable multibeam phased array system 9 and wide-band operation, thanks to its implementation of true-time-delays 10 . By properly tuning the shape of the lens according to the geometrical optics approximation with the goal of focalizing plane waves impinging on the antenna side of the lens to different focal points on the beam-ports side of the lens, one achieves a lens-shaped structure with two angles of curvatures: one on the beam-ports side, and the other on the antenna side 11 . Because the lens is capable of focusing the energy coming from a given direction into its geometrically-associated beam port, the proposed scheme loads each of these ports with a rectifier, thereby channeling the energy coming from any direction to one of the rectifiers as shown in Fig. 1 a. This subsection investigates the effect of varying the number of antenna ports Na and beam ports Nb in the Rotman lens on its maximum array factor and angular coverage. The ( Na , Nb ) set, resulting in the best combination, will define the Rotman lens design parameters used for this work. Structures of varying sizes were designed using Antenna Magus and identical material parameters (substrate, conductors) as the ones of the presented design, before being simulated in CST STUDIO SUITE 2018. The simulated data was then processed in MATLAB to output the array factors created by the respective lens structures using a modified version of Eq. ( 1 ) 12 , presented next in Eq. ( 2 ):
where AF , n , Na , k , d , \(\theta\) and \(\beta\) are, respectively, the lossless array factor, the antenna number, the total number of antenna ports, the wave vector, the spacing between the elements, the direction of radiation and the difference in phase excitation between the elements. Since this formula describes a lossless array with a single antenna port, we introduced the following equation that takes into account the losses induced by the feeding network as well as the introduction of multiple feeding ports.
where \(AF_j\) and \(S_{nj}\) are, respectively, the array factor for beam port j and the S parameters between antenna ports n and beam ports j . The maximum value of the array factors as well as their total (accounting for the aggregated coverage of all ports) 3 dB beamwidths where then tabulated. The five simulated lenses had the following ( Na , Nb ) combinations: (4,3), (8,6) representing the system implemented in this work, (16,12), (32,24) and (64,48). Figure 1 b shows the increase in the array factor until reaching a peak of around 7.8 dB for a lens surrounded by 16 antennas and 12 beam ports, after which the array factor starts dropping, down to approximately 5.2 dB for a 64 antennas structure with 48 beam ports. The array factor reduction is explained by the increased losses within the lens accompanied by the increase of complexity and internal reflections, as the lens grows in electrical size. The same plot shows the decrease in angular coverage from 180° with 4 antennas down to 80° with 64 antennas. This study shows that the combination composed of eight antennas and six beam ports, offers a nearly optimal compromise, with these materials, between a high array factor of 5.95 dB and a 120° total angular coverage, while maintaining a reasonable number of antennas and beam ports. It should be noted that the choice of the number of beam ports is related to the 3dB-beamwidth of the individual antennas, the reason for which will be detailed later.
( a ) Dual combining (RF + DC) enabled by the use of the Rotman lens between the antennas and the rectifiers, ( b ) plot of the simulated maximum array factors and angular coverages for different-size Rotman lenses and ( c ) picture of the fabricated Rotman lens structure.
After setting the number of antenna ports and beam ports, the design was printed on flexible copper-clad Liquid Crystal Polymer (LCP) substrate ( \(\varepsilon _r = 3.02\) and \(\hbox {h}= 180\,\upmu \hbox {m}\) ) using an inkjet-printed masking technique followed by etching, resulting in the structure shown in Fig. 1 c. It should be noted that the use of impedance-matched dummy ports is common with Rotman lenses 13 , 14 , 15 , 16 . Nevertheless, the goal in the implementation hereby described is not (as is usually the case) the generation of clean beam patterns with low side-lobe levels. Here, the lens’ properties are used for harvesting. Consequently, as long as the presence of the side lobes does not significantly interfere with the level of the array factor at broadside, side lobes are of no concern. Such a structure, including eight antenna ports and six beam ports—and, therefore, six radiating directions—was designed, simulated, and tuned. The structure, shown in Fig. 1 c, with the antenna ports connected to matched loads, was then tested in planar and bent configurations—cylinders with different bending radii ranging from 1.5 to 2.5 in. radii—to assess the effect of bending on the S parameters behavior. Figure 2 a shows the measured reflection coefficient of the Rotman lens at beam port 4 for four different scenarios, in comparison with the simulated structure in a planar position. The results reveal the Rotman lens’ ability to be mounted on curved surfaces down to a radius R = 1.5″, while maintaining a stable matching and minuscule losses compared to being held in a planar position.
( a ) Plot of the simulated and measured reflection coefficients at beam port 4 under planar and bent conditions and ( b ) Plots of the maximum array factors and angular directions of beam ports P1, P3 and P5 with respect to frequency.
The gain and angular bandwidths of this structure—defined by the frequency range in which the maximum array factor and angular direction per beam are stable within 3 dB and 5° respectively,—are studied next. The ultimate assessment of these properties involves calculating the beams’ magnitude and angular directions over a wide range of frequencies 17 , in order to ascertain their stability or lack thereof. For this purpose, the maximum array factors were calculated and the beams’ angular directions were extracted and plotted in Fig. 2 b for the first, third and fifth beam ports, P1, P3 and P5, representing the edge, secondary and central beams in this symmetrical structure. These plots prove the unique capabilities offered by the Rotman lens; although the Rotman lens is designed at a specific frequency—28 GHz in this work—this analysis proves that both the magnitude and the angular direction of the beams remain relatively stable over a very wide frequency range. In Fig. 2 b, three plots refer to the maximum array factors of the three beam ports, where minor fluctuations between 4 and 7 dB are observed over the range from 10 to 43 GHz for ports P3 and P5 and similar fluctuations over a fairly reduced frequency range for the extreme edge beam P1. On the same graph, three plots present the angular direction’s stability of P1, P3 and P5 beams, where P3 (in particular) preserves its angular direction over 33 GHz of bandwidth. The lens’ angular coverage resides between ports 1 and 6 and can be extracted from Fig. 2 b. Knowing that the structure is symmetrical and that beam port P1 is at around \({-54}^\circ\) , the overall structure covers an angle larger than 100° in front of the lens, a result further detailed in the next subsection. It should be noted that such a beamwidth is maintained over a large angular bandwidth exceeding 20 GHz, as shown in Fig. 2 b. This study demonstrates the stability and robustness of a low-cost, printed and flexible mm-wave Rotman lens structure, tested with respect to bending and frequency, and supports the choice of such an architecture at the heart of the harvesting system proposed in this work.
Eight of the linear antenna sub-arrays introduced in 8 were then added to the antenna ports of the array, and its beam-ports were extended by microstrip lines to enable their connection to end-launch \({2.92}\,\upmu \hbox {m}\) connectors. The antenna sub-array consists of five serially-fed patch antenna elements, providing an operation centered at 28.55 GHz with a reflection coefficient \(S_{11}\) lower than \({-20}\) dB within this range. Their E-plane beamwidth of about \({18}^\circ\) (provided by the five antennas) is appropriate for most use cases, where environments expand mostly horizontally. Its simulations showed a gain of 13 dBi and a H-plane beamwidth of 80° in the plane perpendicular to the linear array. In this configuration, six beams were chosen to intersect at angles providing 3dB lower gain than broadside. Eight antennas provide a 3dB-beamwidth of 15°, which covers a total of \(6\times {18}^\circ = {108}^\circ\) in front of the array. The design was then also printed on flexible LCP substrate, resulting in the structure shown in Fig. 3 a, mounted on a 1.5″ radius cylinder. The radiation properties of the lens-based antenna system were simulated using the time-domain solver of CST STUDIO SUITE 2018, resulting in the six gain plots shown in Fig. 3 b. The gain of the Rotman lens at every port was also accurately measured using a 20 dBi transmitter horn antenna and by terminating all five remaining ports with a \({50}\,\Omega\) load for every port measurement to guarantee the proper operation of the lens. Both simulated and measured radiation patterns (shown in Fig. 3 b) display a remarkable similarity with a measured gain of approximately 17 dBi, and an angular coverage of around 110°, thereby validating the operation of the antenna array. The gains on the first three ports were also measured for the bent structure over a curvature of 1.5″ radius, shown in Fig. 3 a and compared to the measured results on a planar surface. The previous subsection in addition to previous works 18 , 19 have demonstrated that the performance of the Rotman lens is not deteriorated by wrapping or folding the structure compared to its conventional planar counterpart. However, after adding the antenna arrays, bending the structure can indeed have effects on its phase response, especially if the structure is large and the bending is severe. Figure 3 c shows the gains of P1, P2 and P3 for the two scenarios (three ports only because the structure is symmetrical), demonstrating again the ability of the lens in maintaining a stable gain (especially over the center beams) upon bending. The beam located at the edge, however, suffers additional deterioration in received power under bending, because of the shift of the source away from the broadside of the bent antenna arrays.
( a ) Picture of the flexible Rotman-lens-based antenna array, ( b ) measured (solid lines) and simulated (dashed lines) gains of the antenna array held in a planar position and ( c ) measured gains of the antenna array for beams P1, P2 and P3 only (because of the symmetry of the structure) in planar and bent conditions.
Rotman-lens-based rectenna.
In this section, the fully-flexible rectenna system—based on the Rotman lens and a new DC combiner network—is presented. This architecture, shown in Fig. 4 a, consists of a series of eight antenna sub-arrays attached to the Rotman lens from one side, facing six rectifiers at the opposite side where DC serial combination is implemented. The basic rectenna elements, that are the antenna and the rectifier, are presented in details in 8 . The diode used in this work is the MA4E2038 Schottky barrier diode from Macom. The Rotman-based rectenna was first characterized as a function of its received power density. The system was positioned at a specific harvesting angle (approximately \(-25^\circ\) ) and illuminated with a horn antenna with a gain of 20 dBi, placed at a distance of 52 cm away from the rectenna array, within the far field region starting at 23 cm, and outputting powers ranging from 18 to 25 dBm, corresponding to an RF input power sweep from around − 9 dBm to − 2 dBm. The array was loaded with its optimal load impedance of 1 \(\hbox {k}\Omega\) , corresponding to the optimal load of a single rectifier—since only one rectifier will be “ON” at a time, given that the Rotman lens focalizes all the power to one beam port depending on the direction of the incoming wave—as detailed earlier. The results of this experiment are shown in Fig. 4 b, where the harvested voltages and powers of the array are shown. It can be observed that, at low powers, the Rotman-based rectenna effortlessly produces an output. The Rotman-based rectenna turns on well below − 6 dBm cm −2 , which compares quite favorably to the literature 6 . The output voltage of the rectenna was also measured over its operating frequency range. Like in the first experiment, the system was positioned at the same harvesting angle, at a range of 25 cm away from the source’s horn antenna. The output voltages under open load conditions were recorded and plotted, as shown in Fig. 4 c for the Rotman lens-based rectenna, for \(P_d = {9}\,{\hbox{dBm cm}}^{-2}\) , \(P_d = {10.5}\,{\hbox{dBm cm}}^{-2}\) and \(P_d = {12}\,{\hbox{dBm cm}}^{-2}\) incident power densities. The plots present a wide frequency coverage—from 27.8 to 29.6 GHz.
( a ) Picture of the fully-flexible Rotman-based rectenna, ( b ) plot of the measured voltages and output powers versus incident power density for the Rotman-based rectenna and ( c ) plot of the measured voltages with respect to frequency for the Rotman-based rectenna.
Power summation is very critical when it comes to the unbalanced rectification outputs produced from realistic RF sources, and can be implemented differently depending on its costs and benefits 20 .
This paper does not rely on a direct voltage summation topology (i.e. back-to-back RF diodes); however, it introduces a minimalist architecture relying on a total of \(2\times (N-1)\) bypass diodes, where N is the number of RF or rectifying diodes. Equipped with a low turn-on voltage of 0.1 V, the Toshiba 1SS384TE85LF bypass diodes used in the DC combiner design create a low resistance current path around all other rectifiers that received very low or close to zero RF power. This topology is optimal when only one diode is turned on, which can be assumed if a single, dominant source of power irradiates this particular design from a given direction. This new combiner circuit is shown in the schematic of Fig. 5 a. This simplified schematic—shown for four rectifying diodes—uses different colors to highlight the paths that the current will take for every case where an RF diode turning “ON” while the serially-connected diodes are “OFF”. This DC combiner was then fabricated on a flexible \({125\,\upmu \mathrm{m}}\) -thin polyimide Kapton substrate and connected to the Rotman lens-based rectenna through a series of single connectors to make the entire system fully flexible and bendable. The harvested power under a load of 1 \(\hbox {k}\, \Omega\) versus the angle of incidence of the mm-wave energy source for the Rotman-lens-based rectenna is compared for both rigid (presented in 8 , and relying on \(2\times N\) bypass diodes) and flexible new DC combiners. For this experiment, a horn transmitter antenna was used to send 25 dBm of RF power at 28.5 GHz to the lens placed 70 cm away, as shown in Fig. 5 b, while the array was precisely rotated in angular increments of 5°. Figure 6 a shows that the new DC combiner, with a reduced number of diodes, was able to provide a complete angular coverage of almost 110° over the entire lens spectrum as presented in Fig. 3 b, thus solving the voltage nulling occurring at the first and last ports, using the rigid DC combiner adopted previously in 8 . The new DC combiner offers therefore, an increase of more than 30% in the system’s spatial angular in addition to enabling a fully-bendable structure due to the unique fabrication on flexible Kapton substrate and connection to the rectenna using individual interconnects.
( a ) Rotman-based rectenna power summation network and ( b ) picture of the setup used to measure the angular response of the rectenna.
( a ) Plot of the measured harvested powers by the rectenna with respect to the source’s incidence angle for the two DC combiners, rigid and flexible and ( b ) plots of the measured harvested powers and voltages with respect to the incident power density under different load conditions for the Rotman lens rectenna with and without the flexible DC combiner.
As mentioned earlier, the DC combiner is mainly used with the Rotman-lens-based rectenna to automatically direct the active rectifier’s output to a single DC common port, independent of which port this might be. An alternative to the DC combiner in the Rotman lens-based system, would be to manually connect to the active port if the location of the source were known. To study the effect of the implemented DC combiner on the turn-on sensitivity of the system, the output voltage of the rectenna was measured for a specific source location with and without the combiner over a range of RF transmitted power and load variations; the direction was chosen such that the non-DC-combined rectifier would output its maximum power. Figure 6 b shows eight different plots where three of them represent the harvested power with a direct connection to the active rectifier for 1 \(\hbox {k}\Omega\) , 10 \(\hbox {k}\Omega\) and 100 \(\hbox {k}\Omega\) conditions. Plotted with the same colors are the other three, representing the harvested power with the addition of the DC combiner for the same load values. The last two plots display the measured voltages with and without the combiner under open load conditions. The rectenna was placed 61 cm away from the transmitter horn antenna and the power was swept from 10 to 25 dBm. The results show the performance superiority in all considered load conditions when the contact is made directly to the rectifier and not through the DC combiner. The lens-based system is able to achieve a turn-on power as low as \(-15\,{\hbox{dBm cm}}^{-2}\) in this case. This behavior is explained by the voltage drop introduced by the bypass diodes present in the combiner—that consistently decrease the expected output voltage by 0.1 to 0.2 V—when one or two diodes are, respectively, added to the current path. The variation of load values also shows that the rectenna can achieve better efficiencies at lower loads. More importantly, the reduction in the turn-on sensitivity—the minimum power density required output 10 mV—induced by the combiner is only of about 2 dB in loaded conditions, while the combiner enables an increase in the angular coverage of the rectenna system from about 18° to 110°. The remarkable angular and high-power turn-on sensitivity offered by the Rotman-lens-based rectenna are finally benchmarked using the following table for comparison with several state-of-the-art works, as presented in literature. In Table 1 , the striking performance of the proposed system is displayed, highlighted by its flexibility and ability of achieving an angular coverage as large as 110° at extremely high turn-on sensitivity, thereby allowing mm-wave long-range harvesting in ad-hoc and conformal-mounting implementations.
This section displays the operation of the Rotman-lens-based system under different bending scenarios. This and previous work 18 , 19 show that the lens is able to maintain an efficient electromagnetic energy distribution across the output ports under convex and concave flexing conditions. The lens-based rectenna was placed on cylinders with different curvatures, 70 cm away from the transmitter sending 25 dBm of power at 28.5 GHz, as shown on Fig. 7 a. The voltage was collected using a load of 1 \(\hbox {k}\Omega\) for the planar and three bent conditions and plotted in Fig. 7 b with respect to the source’s angle of incidence. The graph shows an unprecedented consistency and stability in the system’s scavenging and rectification abilities, knowing that several sub-systems are exposed to warping and the pressures of bending: the antenna sub-arrays, the Rotman lens and the rectifiers. Slight attenuation can be observed at the edges, but the system otherwise performs unimpeded by the bending. This remarkable property qualifies this system as a perfect candidate for use in wearables, smart phones and ubiquitous, conformal 5G energy harvesters for IoT nodes.
( a ) Picture of the flexible Rotman lens-based rectenna placed on a 1.5″ radius cylinder and ( b ) measured harvested powers versus incidence angles for different curvatures, ( c ) long-range harvesting testing setup.
As described earlier, one of the main appeals of the proposed approach is its ability to use the high EIRPs allowed for 5G base-stations while guaranteeing an extended beam angular coverage, which is a necessary feature for ad-hoc ubiquitous harvesting implementations. In order to demonstrate the lens based-rectenna for longer-distance harvesting and detect that maximum range, a high-performance antenna system—comprised of a 19 dBi conical horn antenna and a 300 mm-diameter PTFE dielectric lens (for high directivity) providing an additional 10 dB of gain—was used as shown in Fig. 7 c. With a transmitted power of 25 dBm (and an associated EIRP of approximately 54 dBm), corresponding to an incident power density of approximately − 6 dBm cm −2 , the lens-based rectenna displayed an extended range of 2.83 m under open load conditions, with an output voltage around 10 mV, thereby demonstrating (to our knowledge) the longest-ranging rectenna demonstration at mm-wave frequencies. With a transmitter emitting the allowable 75 dBm EIRP, the theoretical maximum reading range of this rectenna could extend to 16 m. In addition, the use of advanced diodes—designed for applications within the 5G bands and enabling rectifiers’ sensitivities similar to that common at lower (UHF) frequencies—are showing a potential path towards achieving a turn-on sensitivity of the rectifiers as low as − 30 dBm 21 , 22 . If this were practically applied to the Rotman lens system presented in this work, the harvesting range could be extended beyond 180 m (where the received power density for a transmitted power of 75 dBm is \({7.8}\,\upmu \hbox {W cm}^{-2}\) ), which is only slightly smaller than the recommended cell size of 5G networks 23 . This observation enables the striking idea that future 5G networks could be used not only for tremendously-rapid communications, but also as a ubiquitous wireless power grid for IoT devices.
Through the use of the Rotman lens, this paper demonstrates that the usual paradigm constrained by the (often considered fundamental) trade-off between the angular coverage and the turn-on sensitivity of a wireless harvesting system can be broken. Using the reported architecture, one can design and fabricate flexible mm-wave harvesters that can cover wide areas of space while being electrically large and benefit from the associated improvements in link budget (from source to harvester) and, more importantly, turn-on sensitivity. The approach has been shown, however, to only be scalable up to the degree where the additional incremental losses introduced by the growing lens counterbalance the increase in the aperture of the rectenna. Nevertheless, this inflection point only appears (in the particular context considered in this paper) after the arraying of 16 elements, or up to a scale of \(8\lambda\) . In the 5G Frequency Range 2 (FR2), this translates to harvesters of 4.5 cm to 9.6 cm in size, which are perfectly suited for wearable and ubiquitous IoT implementations. With the advent of 5G networks and their associated high allowed EIRPs and the availability of diodes with high turn-on sensitivities at 5G frequencies, several \({\upmu \hbox {W}}\) of DC power (around 6 \({\upmu \hbox {W}}\) with 75 dBm EIRP) can be harvested at 180 m. Such properties may trigger the emergence of 5G-powered nodes for the IoT and, combined with the long-range capabilities of mm-wave ultra-low-power backscatterers 24 , of long-range passive mm-wave RFIDs.
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This work was supported by the Air Force Research Laboratory and the NSF-EFRI. The work was performed in part at the Georgia Tech Institute for Electronics and Nanotechnology, a member of the National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the National Science Foundation (Grant ECCS-1542174).
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A.E. and J.H. conceived the idea, designed, and simulated the antenna arrays, rectifiers, Rotman lens, DC combiners and full rectennas. They also performed the measurements, interpreted results and wrote the paper. M.T. supervised the research and contributed to the general concept and interpretation of the results. All authors reviewed the manuscript.
Correspondence to Aline Eid .
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Eid, A., Hester, J.G.D. & Tentzeris, M.M. 5G as a wireless power grid. Sci Rep 11 , 636 (2021). https://doi.org/10.1038/s41598-020-79500-x
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The growing prevalence of high-speed wireless communication devices, from 5G mobile phones to sensors for autonomous vehicles, is leading to increasingly crowded airwaves. This makes the ability to block interfering signals that can hamper device performance an even more important — and more challenging — problem.
With these and other emerging applications in mind, MIT researchers demonstrated a new millimeter-wave multiple-input-multiple-output (MIMO) wireless receiver architecture that can handle stronger spatial interference than previous designs. MIMO systems have multiple antennas, enabling them to transmit and receive signals from different directions. Their wireless receiver senses and blocks spatial interference at the earliest opportunity, before unwanted signals have been amplified, which improves performance.
Key to this MIMO receiver architecture is a special circuit that can target and cancel out unwanted signals, known as a nonreciprocal phase shifter. By making a novel phase shifter structure that is reconfigurable, low-power, and compact, the researchers show how it can be used to cancel out interference earlier in the receiver chain.
Their receiver can block up to four times more interference than some similar devices. In addition, the interference-blocking components can be switched on and off as needed to conserve energy.
In a mobile phone, such a receiver could help mitigate signal quality issues that can lead to slow and choppy Zoom calling or video streaming.
“There is already a lot of utilization happening in the frequency ranges we are trying to use for new 5G and 6G systems. So, anything new we are trying to add should already have these interference-mitigation systems installed. Here, we’ve shown that using a nonreciprocal phase shifter in this new architecture gives us better performance. This is quite significant, especially since we are using the same integrated platform as everyone else,” says Negar Reiskarimian, the X-Window Consortium Career Development Assistant Professor in the Department of Electrical Engineering and Computer Science (EECS), a member of the Microsystems Technology Laboratories and Research Laboratory of Electronics (RLE), and the senior author of a paper on this receiver .
Reiskarimian wrote the paper with EECS graduate students Shahabeddin Mohin, who is the lead author, Soroush Araei, and Mohammad Barzgari, an RLE postdoc. The work was recently presented at the IEEE Radio Frequency Circuits Symposium and received the Best Student Paper Award.
Blocking interference
Digital MIMO systems have an analog and a digital portion. The analog portion uses antennas to receive signals, which are amplified, down-converted, and passed through an analog-to-digital converter before being processed in the digital domain of the device. In this case, digital beamforming is required to retrieve the desired signal.
But if a strong, interfering signal coming from a different direction hits the receiver at the same time as a desired signal, it can saturate the amplifier so the desired signal is drowned out. Digital MIMOs can filter out unwanted signals, but this filtering occurs later in the receiver chain. If the interference is amplified along with the desired signal, it is more difficult to filter out later.
“The output of the initial low-noise amplifier is the first place you can do this filtering with minimal penalty, so that is exactly what we are doing with our approach,” Reiskarimian says.
The researchers built and installed four nonreciprocal phase shifters immediately at the output of the first amplifier in each receiver chain, all connected to the same node. These phase shifters can pass signal in both directions and sense the angle of an incoming interfering signal. The devices can adjust their phase until they cancel out the interference.
The phase of these devices can be precisely tuned, so they can sense and cancel an unwanted signal before it passes to the rest of the receiver, blocking interference before it affects any other parts of the receiver. In addition, the phase shifters can follow signals to continue blocking interference if it changes location.
“If you start getting disconnected or your signal quality goes down, you can turn this on and mitigate that interference on the fly. Because ours is a parallel approach, you can turn it on and off with minimal effect on the performance of the receiver itself,” Reiskarimian adds.
A compact device
In addition to making their novel phase shifter architecture tunable, the researchers designed them to use less space on the chip and consume less power than typical nonreciprocal phase shifters.
Once the researchers had done the analysis to show their idea would work, their biggest challenge was translating the theory into a circuit that achieved their performance goals. At the same time, the receiver had to meet strict size restrictions and a tight power budget, or it wouldn’t be useful in real-world devices.
In the end, the team demonstrated a compact MIMO architecture on a 3.2-square-millimeter chip that could block signals which were up to four times stronger than what other devices could handle. Simpler than typical designs, their phase shifter architecture is also more energy efficient.
Moving forward, the researchers want to scale up their device to larger systems, as well as enable it to perform in the new frequency ranges utilized by 6G wireless devices. These frequency ranges are prone to powerful interference from satellites. In addition, they would like to adapt nonreciprocal phase shifters to other applications.
This research was supported, in part, by the MIT Center for Integrated Circuits and Systems.
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College of engineering, al jamal wins best paper award at 2024 ieee international microwave symposium.
Al Jamal’s research on origami-inspired phased array antennas represents a quantum leap in antenna reconfigurability at mm-wave frequencies and a paradigm shift in massive MIMO applications and beyond-5G communication.
Georgia Tech School of Electrical and Computer Engineering Ph.D. candidate Hani Al Jamal won first-place in the Student Paper Competition (Best Paper Award) at the 2024 IEEE International Microwave Symposium (IMS), held June 17-20 in Washington, DC.
This prestigious award recognizes top technical papers at the conference. His paper was selected out of the 306 total submissions eligible for this award this year.
His paper, “Beyond Planar: An Additively Manufactured, Origami-Inspired Shape-Changing, and RFIC-Based Phased Array for Near-Limitless Radiation Pattern Reconfigurability in 5G/mm-Wave Applications,” was co-authored by fellow ECE Ph.D. candidates Chenhao Hu and Nathan Wille, in collaboration with George Mason University Electrical and Computer Engineering professor Kai Zeng.
Al Jamal and his team successfully demonstrated the first-ever additively manufactured, origami-inspired, shape-changing phased array at mm-wave frequencies, showcasing near-limitless reconfigurability. This work represents a significant leap, opening impactful opportunities for the advancement of massive MIMO and beyond-5G communication.
An origami-inspired, shape-changing phased array combines this traditional antenna function with the ability to electronically control the direction of the signal and mechanically change its shape through folding structures inspired by origami. This makes the antenna highly adaptable.
Al Jamal has been enrolled in the ECE Ph.D. program since 2022, and is a member of the ATHENA Lab , where he is advised by ECE Professor Manos Tentzeris .
He received his bachelor’s degree in electrical and computer engineering from the American University of Beirut with high distinction.
His research interests include the use of additive manufacturing techniques in designing highly integrated, heterogeneous, and conformal/flexible RF systems encompassing RF front-end circuits, antennas, and packaging up to mm-wave frequencies. He is also keen on advocating engineering education to high school and undergraduate students.
Through his research, Al Jamal aspires to design and build communication devices and RF electronics that draw inspiration from origami and art, leading to enhanced functionality and physical flexibility to seamlessly integrate with human-centered devices, thereby enabling more efficient and integrated communication networks for digital awareness.
Zachary Winiecki
The Information Systems (IS) group studies novel tools and techniques that help organizations use their information systems to support better operational decision making.
Information Systems are at the core of modern-day organizations. Both within and between organizations. The Information Systems group studies tools and techniques that help to use them in the best possible way, to get the most value out of them.
In order to do that, the IS group helps organizations to: (i) understand the business needs and value propositions and accordingly design the required business and information system architecture; (ii) design, implement, and improve the operational processes and supporting (information) systems that address the business need, and (iii) use advanced data analytics methods and techniques to support decision making for improving the operation of the system and continuously reevaluating its effectiveness.
We do so in various sectors from transportation and logistics, mobility services, high-tech manufacturing, service industry, and e-commerce to healthcare.
Against this background, IS research concentrates on the following topics:
We work on Information Systems topics in three related research areas.
Business Engineering (BE) investigates and develops new concepts, methods, and techniques - including novel data-driven approaches - for the…
Process Engineering (PE) develops integrated tools and techniques for data-driven decision support in the design and execution of…
AI for Decision-Making (AI4DM) develops methods, techniques and tools for AI-driven decision making in operational business process.
We focus on the application of Information Systems in the following domains.
The digital transformation of industry is leveraged by Information Systems providing integrated data and process management and AI-enabled…
Information Systems are the backbone of modern health(care) ecosystems. They are critical for clinical research, clinical operations, and…
Information Systems focuses on the business architecture design of new mobility solutions that are safe, efficient, affordable and…
Information Systems facilitate monitoring and planning of transportation and logistics resources. By doing so, they ultimately help to…
Service organizations, including banks, insurance companies, and governmental bodies, fully rely on information provisioning to do their…
Maryam razavian, zaharah bukhsh, konstantinos tsilionis, baris ozkan, laura genga, pieter van gorp, banu aysolmaz, karolin winter, alexia athanasopoulou, yingqian zhang, laurens bliek, hendrik baier.
Our most recent peer reviewed publications
A revised cognitive mapping methodology for modeling and simulation, backpropagation through time learning for recurrence-aware long-term cognitive networks, an explainable data-driven decision support framework for strategic customer development, data-driven aggregate modeling of a semiconductor wafer fab to predict wip levels and cycle time distributions.
We encourage innovation from our research. This is why we share the open-source codes from our research projects.
Please check out the TU/e vacancy pages for opportunities within our group.
If you are a student, potential sponsor or industrial partner and want to work with us, please contact the IS secretariat or the Information Systems group chair, dr.ir. Remco Dijkman
Postal address.
This year, from more than 11,500 paper submissions, the CVPR 2024 Awards Committee selected the following 10 winners for the honor of Best Papers during the Awards Program at CVPR 2024, taking place now through 21 June at the Seattle Convention Center in Seattle, Wash., U.S.A.
Best Papers
Honorable mention papers included, “ EventPS: Real-Time Photometric Stereo Using an Event Camera ” and “ pixelSplat: 3D Gaussian Splats from Image Pairs for Scalable Generalizable 3D Reconstruction. ”
Best Student Papers
There also were four honorable mentions in this category this year: “ SpiderMatch: 3D Shape Matching with Global Optimality and Geometric Consistency ”; “ Image Processing GNN: Breaking Rigidity in Super-Resolution; Objects as Volumes: A Stochastic Geometry View of Opaque Solids ;” and “ Comparing the Decision-Making Mechanisms by Transformers and CNNs via Explanation Methods. ”
“We are honored to recognize the CVPR 2024 Best Paper Awards winners,” said David Crandall, Professor of Computer Science at Indiana University, Bloomington, Ind., U.S.A., and CVPR 2024 Program Co-Chair. “The 10 papers selected this year – double the number awarded in 2023 – are a testament to the continued growth of CVPR and the field, and to all of the advances that await.”
Additionally, the IEEE Computer Society (CS), a CVPR organizing sponsor, announced the Technical Community on Pattern Analysis and Machine Intelligence (TCPAMI) Awards at this year’s conference. The following were recognized for their achievements:
“The TCPAMI Awards demonstrate the lasting impact and influence of CVPR research and researchers,” said Walter J. Scheirer, University of Notre Dame, Notre Dame, Ind., U.S.A., and CVPR 2024 General Chair. “The contributions of these leaders have helped to shape and drive forward continued advancements in the field. We are proud to recognize these achievements and congratulate them on their success.”
About the CVPR 2024 The Computer Vision and Pattern Recognition Conference (CVPR) is the preeminent computer vision event for new research in support of artificial intelligence (AI), machine learning (ML), augmented, virtual and mixed reality (AR/VR/MR), deep learning, and much more. Sponsored by the IEEE Computer Society (CS) and the Computer Vision Foundation (CVF), CVPR delivers the important advances in all areas of computer vision and pattern recognition and the various fields and industries they impact. With a first-in-class technical program, including tutorials and workshops, a leading-edge expo, and robust networking opportunities, CVPR, which is annually attended by more than 10,000 scientists and engineers, creates a one-of-a-kind opportunity for networking, recruiting, inspiration, and motivation.
CVPR 2024 takes place 17-21 June at the Seattle Convention Center in Seattle, Wash., U.S.A., and participants may also access sessions virtually. For more information about CVPR 2024, visit cvpr.thecvf.com .
About the Computer Vision Foundation The Computer Vision Foundation (CVF) is a non-profit organization whose purpose is to foster and support research on all aspects of computer vision. Together with the IEEE Computer Society, it co-sponsors the two largest computer vision conferences, CVPR and the International Conference on Computer Vision (ICCV). Visit thecvf.com for more information.
About the IEEE Computer Society Engaging computer engineers, scientists, academia, and industry professionals from all areas and levels of computing, the IEEE Computer Society (CS) serves as the world’s largest and most established professional organization of its type. IEEE CS sets the standard for the education and engagement that fuels continued global technological advancement. Through conferences, publications, and programs that inspire dialogue, debate, and collaboration, IEEE CS empowers, shapes, and guides the future of not only its 375,000+ community members, but the greater industry, enabling new opportunities to better serve our world. Visit computer.org for more information.
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The 5G network is a promising technology that revolutionizes and connects the global world through seamless connectivity. This paper presents a survey on 5G networks on how, in particular, it to address the drawbacks of foregoing cellular standards and be a potential key facilitator for the future as well as the extant technologies such as IoT ...
In this paper, we represent thorough overview of 5G the next generation mobile technology. We mainly throws light on 5G network architecture, 5G radio spectrum, ultra-dense radio access networks (UDRAN), traffic offloading of mobile, cognitive radio (CR), software defined radio (SDR), software defined networking (SDN), mixed infrastructure, and ...
In the near future, i.e., beyond 4G, some of the prime objectives or demands that need to be addressed are increased capacity, improved data rate, decreased latency, and better quality of service. To meet these demands, drastic improvements need to be made in cellular network architecture. This paper presents the results of a detailed survey on the fifth generation (5G) cellular network ...
Wireless Communication has evolved over the past three to four decades, the evolution brought about major changes in the type of technology been used, the speed of data transfer, capacity latency, and network coverage, amongst several other key factors. Four generations have been established as a result of the constant improvement of Wireless Communication. Fifth Generation (5G) is referred to ...
The objective of this paper is comprehensive study related to 5G technology of mobile communication. Existing research work in mobile communication is related to 5G technology. In 5G, researches are related to the development of World Wide Wireless Web (WWWW), Dynamic Adhoc Wireless Networks (DAWN) and Real Wireless Communication. The most important technologies for 5G technologies are 802.11 ...
According to the GSMA forecast, 5G networks will cover one-third of the world's population in 2025, which impact on the mobile industry and its customers will be profound. Due to the huge cost of 5G network construction, many operators are seeking for a cost-saving way to upgrade existing 4G networks to 5G networks. Based on the detailed study of 5G wireless network architecture, this article ...
Topics. Research areas in 5G technology. Research areas in 5G Technology. We are currently on the cusp of 5G rollout. As industry experts predict, 5G deployments will gain momentum, and the accessibility of 5G devices will grow in 2020 and beyond. But as the general public waits for mass-market 5G devices, our understanding of this new ...
ecosystem. Once released, the IEEE 5G and Beyond Technology Roadmap will be periodically updated with forecasts for three-, five-, and 10-year horizons. This white paper describes the IEEE 5G and Beyond Technology Roadmap process and summarizes the need for collaboration among all stakeholders in industry, academia, and standards development
Research papers on a wide array of topics are helping to advance the field and bring the vision of 5G technology and IoT connectivity into focus. Realizing the potential of 5G and IoT through research. The 5G network represents the best chance for an ever-growing array of wirelessly connected devices to realize their full potential.
The IEEE 5G Initiative is ... The initiative aims to identify trends in innovation and technology, as well as report on research being conducted in areas such as application services, millimeter ...
Communication technology is one of the core technologies of the Internet of things (IOT). And communication technology is the basic component of realizing the IOT. The IOT can be connected through different types of communication networks. Meanwhile, the latest development of 5G communication has unique advantages. This paper introduces and summarizes the characteristics and advantages of 5G ...
The aim of this paper is to follow the technology over the years and to provide a comprehensive and integrated evidence-driven account of its build-up. ... but also with digital, sensors and computer engineering. Among the top venues for 5G-related research, IEEE journals are dominant. 9 The earliest two publications on 5G in our database came ...
Such speeds offer exciting possibilities for new developments and applications in numerous industries and economic sectors. E-health services. For example, 5G speeds allow telemedicine services to enhance their doctor-patient relationships by decreasing troublesome lag times in calls. This helps patients return to the experience of intimacy ...
In this paper, we provide a comprehensive overview of the ongoing research on the enabling technologies for the G network. We present the status of work on the important technologies and service models for the next generation of mobilesystemsandnetworks.e remainderofthispaperis organizedasfollows.Anewmodelfornetworkcontrol,SDN,
The faster small cell technology advances, the sooner consumers will have specific 5G devices connected to 5G-only Internet. Security-oriented research. Security is also quickly becoming a major area of focus amid the push for a global 5G rollout. Earlier iterations of cellular technology were based primarily on hardware.
Submission Deadline: 31 January 2020. IEEE Access invites manuscript submissions in the area of Secure Communication for the Next Generation 5G and IoT Networks. New forms of technology continue to permeate modern day society, and can have significant impacts on business, government and personal interactions.
Abstract. In wireless communication, Fifth Generation (5G) Technology is a recent generation of mobile networks. In this paper, evaluations in the field of mobile communication technology are presented. In each evolution, multiple challenges were faced that were captured with the help of next-generation mobile networks.
Recently, the rapid development of 5G trusted communication technology has greatly contributed to economic and social progress, greatly improving production efficiency. However, the rapidly developing 5G communication technology will inevitably add complexity to the maintenance of network lines and energy scheduling of smart grids. In order to better safeguard the operation and maintenance of ...
A mm-wave ultra-long-range energy-autonomous printed RFID-enabled van-Atta wireless sensor: At the crossroads of 5g and IoT. In 2017 IEEE MTT-S International Microwave Symposium (IMS) 1557-1560 ...
6G W ireless Communications: Future T echnologies. and Research Challenges. Samar El meadawy 1and RaedM .S hubair 23. 1 Information Engineering and Technology Department, German University in ...
South Korea is the country which arrayed the. first 5G networks and the state is expe cted to stay in. the lead as far as penetration of the technology goes, by 2025, nearly 60 percent of mobile ...
The nature of 5G is a functionally vital, systematic and open-ended syst em of ultra-modern. technology which supports various applicatio ns. The 5G core network drives the u tility of 5G networks ...
The growing prevalence of high-speed wireless communication devices, from 5G mobile phones to sensors for autonomous vehicles, is leading to increasingly crowded airwaves. This makes the ability to block interfering signals that can hamper device performance an even more important — and more challenging — problem.
The manufactured filter has a minimum in-band insertion loss of ~ 1.5 dB, a 3 dB bandwidth of about 170 MHz, and a stopband rejection of nearly -30 dB. The experimental results verify the design and show great applications for 5G communication and beyond.
Georgia Tech School of Electrical and Computer Engineering Ph.D. candidate Hani Al Jamahl won first-place in the Student Paper Competition (Best Paper Award) at the 2024 IEEE International Microwave Symposium (IMS), held June 17-20 in Washington, DC.This prestigious award recognizes top technical papers at the conference. His paper was selected out of the 306 total submissions eligible for ...
In order to do that, the IS group helps organizations to: (i) understand the business needs and value propositions and accordingly design the required business and information system architecture; (ii) design, implement, and improve the operational processes and supporting (information) systems that address the business need, and (iii) use advanced data analytics methods and techniques to ...
SEATTLE, 19 June 2024 - Today, during the 2024 Computer Vision and Pattern Recognition (CVPR) Conference opening session, the CVPR Awards Committee announced the winners of its prestigious Best Paper Awards, which annually recognize top research in computer vision, artificial intelligence (AI), machine learning (ML), augmented, virtual and mixed reality (AR/VR/MR), deep learning, and much more.