مجال التميز | تميز دراسي وبحثي + جائزة تفوقية |
البحوث المنشورة |
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البحث (1): | |
عنوان البحث: |
Optimum resource allocation in optical wireless systems with energy-efficient fog and cloud architectures |
رابط إلى البحث: |
https://royalsocietypublishing.org/doi/pdf/10.1098/rsta.2019.0188 |
تاريخ النشر: |
02/03/2020 |
موجز عن البحث: |
Optical wireless communication (OWC) is a promising technology that can provide high data rates while supporting multiple users. The optical wireless (OW) physical layer has been researched extensively, however, less work was devoted to multiple access and how the OW front end is connected to the network. In this paper, an OWC system which employs a wavelength division multiple access (WDMA) scheme is studied, for the purpose of supporting multiple users. In addition, a cloud/fog architecture is proposed for the first time for OWC to provide processing capabilities. The cloud/fog-integrated architecture uses visible indoor light to create high data rate connections with potential mobile nodes. These OW nodes are further clustered and used as fog mini servers to provide processing services through the OW channel for other users. Additional fog-processing units are located in the room, the building, the campus and at the metro level. Further processing capabilities are provided by remote cloud sites. Two mixed-integer linear programming (MILP) models were proposed to numerically study networking and processing in OW systems. The first MILP model was developed and used to optimize resource allocation in the indoor OWC systems, in particular, the allocation of access points (APs) and wavelengths to users, while the second MILP model was developed to optimize the placement of processing tasks in the different fog and cloud nodes available. The optimization of tasks placement in the cloud/fog-integrated architecture was analysed using the MILP models. Multiple scenarios were considered where the mobile node locations were varied in the room and the amount of processing and data rate requested by each OW node was varied. The results help to identify the optimum colour and AP to use for communication for a given mobile node location and OWC system configuration, the optimum location to place processing and the impact of the network architecture. |
المؤتمرات العلمية |
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المؤتمر (1): | |
عنوان المؤتمر: |
21st International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
09/07/2019 |
مكان الإنعقاد: |
Angers, France |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Transmitter Diversity with Beam Steering |
ملخص المشاركة: |
Providing high data rates is one of the drivers in visible light communication (VLC) systems. This paper introduces a VLC system that employs angle diversity transmitters with beam steering to provide high data rates. In this work, red, yellow, green, and blue (RYGB) laser diodes (LD) are used as transmitters to obtain a high modulation bandwidth. Two types of RYGB LDs units are used in this paper: angle diversity transmitters (ADT) RYGB LDs light unit (for illumination and communication) and RYGB LDs light unit (for illumination). In addition, a four branch angle diversity receiver (ADR) is used where we study the delay spread and SNR. The proposed system was compared to the normal VLC system. A data rate up to 22.8 Gb/s was achieved using simple on-off-keying (OOK) modulation. |
الرابط: | |
المؤتمر (2): | |
عنوان المؤتمر: |
21st International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
09/07/2019 |
مكان الإنعقاد: |
Angers, France |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: | Optimized Resource Allocation in Multi-User WDM VLC Systems |
ملخص المشاركة: |
In this paper, we address the optimization of wavelength resource allocation in multi-user WDM Visible Light Communication (VLC) systems. A Mixed Integer Linear Programming (MILP) model that maximizes the sum of Signal-to-Interference-plus-Noise-Ratio (SINR) for all users is utilized. The results show that optimizing the wavelength allocation in multi-user WDM VLC systems can reduce the impact of the interference and improve the system throughput in terms of the sum of data rates for up to 7 users |
الرابط: | |
المؤتمر (3): | |
عنوان المؤتمر: |
21st International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
09/07/2019 |
مكان الإنعقاد: |
Angers, France |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Visible Light Optical Data Centre Links |
ملخص المشاركة: |
Providing high data rates is one of the big concerns in visible light communication (VLC) systems. This paper introduces a data centre design that use a VLC system for downlink communication. In this work, RYGB laser diodes (LD) are used as transmitters to obtain a high modulation bandwidth. Three types of receivers, wide field of view receiver (WFOVR), 3 branches angle diversity receiver (ADR) and 50 pixels imaging receiver (ImR) are used to examine delay spread and SNR. The proposed system achieved data rates up to 14.2 Gbps using simple on-off-keying (OOK) modulation. |
الرابط: | |
المؤتمر (4): | |
عنوان المؤتمر: |
2019 IEEE International Conference on Computational Science and Engineering (CSE) and IEEE International Conference on Embedded and Ubiquitous Computing (EUC) |
تاريخ الإنعقاد: |
01/08/2019 |
مكان الإنعقاد: |
New York, NY, USA |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Infrared Uplink Design for Visible Light Communication (VLC) Systems with Beam Steering |
ملخص المشاركة: |
Providing uplink high data rate is one of the big concerns in visible light communication (VLC) systems. This paper introduces an uplink VLC system based on an infrared transmitter with beam steering to provide high data rates. In this work, a 4 branches angle diversity receiver (ADR) is used and the resultant delay spread and SNR are examined. The proposed system achieved data rates up to 3.57 Gb/s using simple on-off-keying (OOK). |
الرابط: | |
المؤتمر (5): | |
عنوان المؤتمر: |
IEEE Conference on Standards for Communications and Networking |
تاريخ الإنعقاد: |
28-30 October 2019 |
مكان الإنعقاد: |
Granada, Spain |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Optical Wireless Cabin Communication System |
ملخص المشاركة: |
Offering a high data rate to users inside the cabin is attractive for the aircraft building companies. This paper presents an optical wireless system that uses visible light for transmitting data. The reading light for each seat is used as a transmitter in this work to offer high data rates. Red, yellow, green, and blue (RYGB) laser diode (LD) are utilised in each reading light to obtain a high modulation bandwidth. Two types of reading lights based on angle diversity transmitter (ADT) units are utilised in this paper for illumination and communication. Additionally, two kinds of optical receivers are used: four branches angle diversity receiver (ADR) and 25 pixels imaging receiver (ImR). The delay spread and the signal to interference and noise ratio (SINR) are evaluated. The proposed system can offer high data rates up to 22.8 Gbps for each user by using simple on-off-keying (OOK) modulation. |
الرابط: | |
المؤتمر (6): | |
عنوان المؤتمر: |
IEEE Conference on Standards for Communications and Networking |
تاريخ الإنعقاد: |
28-30 October 2019 |
مكان الإنعقاد: |
Granada, Spain |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Co-existence of Micro, Pico and Atto Cells in Optical Wireless Communication |
ملخص المشاركة: |
Interference between cells or users can have a significant impact on the quality of optical wireless communication (OWC) links. This paper studies the co-existence of infrared based Micro cells with Visible light communication based Pico and Atto Cells for downlink communication. The signal to noise ratio (SNR) of each cell and the signal to interference and noise ratio (SINR) between cells are evaluated when an angle diversity receiver and an imaging receiver are used. The results show that Atto cell systems provide higher SNR and data rates compared to the Pico cell systems which provide higher SNR and data rates compared to Micro cell systems. The Micro cell systems however provide mobility as they provide a larger coverage area, followed by the Pico cell systems. |
الرابط: | |
المؤتمر (7): | |
عنوان المؤتمر: |
2020 2nd 6G Wireless Summit (6G SUMMIT) |
تاريخ الإنعقاد: |
17/03/2020 |
مكان الإنعقاد: |
Levi, Finland |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Optimum Resource Allocation in 6G Optical Wireless Communication Systems |
ملخص المشاركة: |
Optical wireless communication (OWC) systems are a promising communication technology that can provide high data rates into the tens of Tb/s and can support multiple users at the same time. This paper investigates the optimum allocation of resources in wavelength division multiple access (WDMA) OWC systems to support multiple users. A mixed-integer linear programming (MILP) model is developed to optimise the resource allocation. Two types of receivers are examined, an angle diversity receiver (ADR) and an imaging receiver (ImR). The ImR can support high data rates up to 14 Gbps for each user with a higher signal to interference plus noise ratio (SINR). The ImR receiver provides a better result compared to the ADR in term of channel bandwidth, SINR and data rate. Given the highly directional nature of light, the space dimension can be exploited to enable the co-existence of multiple, spatially separated, links and thus aggregate data rates into the Tb/s. We have considered a visible light communication (VLC) setting with four wavelengths per access point (red, green, yellow and blue). In the infrared spectrum, commercial sources exist that can support up to 100 wavelengths, significantly increasing the system aggregate capacity. Other orthogonal domains can be exploited to lead to higher capacities in these future systems in 6G and beyond. |
الرابط: | |
المؤتمر (8): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Impact of Room Size on WDM Optical Wireless Links with Multiple Access Points and Angle Diversity Receivers |
ملخص المشاركة: |
Optical wireless communication (OWC) systems have been the subject of attention as a promising wireless communication technology that can offer high data rates and support multiple users simultaneously. In this paper, the impact of room size is investigated when using wavelength division multiple access (WDMA) in conjunction with an angle diversity receiver (ADR). Four wavelengths (red, yellow, green and blue) can be provided in this work based on the RYGB LDs transmitter used. Three room sizes are considered with two 8-user scenarios. A mixed-integer linear programming (MILP) model is proposed for the purpose of optimising the resource allocation. The optical channel bandwidth, SINR and data rate have been calculated for each user in both scenarios in all rooms. Room A, which is the largest room, can provide a higher channel bandwidth and SINR compared to the other rooms. However, all rooms can provide a data rate above 5 Gbps in both scenarios. |
الرابط: | |
المؤتمر (9): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Data centre optical wireless downlink with WDM and multi access point support |
ملخص المشاركة: |
The ability to provide very high data rates is a significant benefit of optical wireless communication (OWC) systems. In this paper, an optical wireless downlink in a data centre that uses wavelength division multiple access (WDMA) is designed. Red, yellow, green and blue (RYGB) laser diodes (LDs) are used as transmitters to provide a high modulation bandwidth. A WDMA scheme based on RYGB LDs is used to provide communication for multiple racks at the same time from the same light unit. Two types of optical receivers are examined in this study; an angle diversity receiver (ADR) with three branches and a 10 pixel imaging receiver (ImR). The proposed data centre achieves high data rates with a higher signal-to-interference-plus-noise ratio (SINR) for each rack while using simple on-off-keying (OOK) modulation. |
الرابط: | |
المؤتمر (10): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Data Center Top of Rack Switch to Multiple Spine Switches Optical Wireless Uplink |
ملخص المشاركة: |
Infrared (IR) uplinks can achieve high data rates, which are essential in a range of applications. This paper introduces a novel approach to enable data centre uplink communication. We introduce a novel method to enable communication between racks and spine switches. In our proposed data centre, we consider three racks, each of which has its own angle diversity transmitter (ADT) that is located on top of the rack. Four wide field of view receivers are fixed to the ceiling of the data centre. Each such receiver is connected to a spine switch. We evaluate the performance of our proposed system when each link operates at a data rate above 2.8 Gb/s. Multiple links can be used to achieve higher data rates using the space or wavelength dimensions. The results show that our proposed system has the ability to work at a high data rate with good performance while using simple on-off-keying. |
الرابط: | |
المؤتمر (11): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
NOMA Visible Light Communication System with Angle Diversity Receivers |
ملخص المشاركة: |
In this paper, a non-orthogonal multiple access (NOMA) visible light communication (VLC) system is investigated. The system uses angle diversity receivers (ADRs) to provide high data rates. The ADR has 4 branches, each directed to a different direction. An 8m x 4m sized room is modelled to study the resource allocation to users according to their channel conditions to maximize the data rate. The results show that using ADRs improves the data rate by an average of 35% compared to a system using wide FOV receivers. |
الرابط: | |
المؤتمر (12): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Resilience in Optical Wireless Systems |
ملخص المشاركة: |
High reliability and availability of communication services is a key requirement that needs to be ensured by service providers. Since the direct line-of-sight (LOS) beam is prone to blockage in indoor optical wireless communication systems, a backup link needs to be at hand in case of blockage, and hence channel allocation algorithms should be blockage-aware. In this paper, the impact of beam blockage due to a disc with varying size and distance from the receiver is studied where blockage is quantitatively evaluated using percentage blockage for 512 room locations at 25 cm separation. It was found that assigning two links with maximum separation between the serving access points can reduce or eliminate blockage compared to the case when resilience is not implemented. Increasing the number of allocated access points per user further increases resilience. |
الرابط: | |
المؤتمر (13): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Resource Allocation in Co-Existing Optical Wireless HetNets |
ملخص المشاركة: |
In multi-user optical wireless communication (OWC) systems interference between users and cells can significantly affect the quality of OWC links. Thus, in this paper, a mixed-integer linear programming (MILP) model is developed to establish the optimum resource allocation in wavelength division multiple access (WDMA) optical wireless systems. Consideration is given to the optimum allocation of wavelengths and access points (Aps) to each user to support multiple users in an environment where Micro, Pico and Atto Cells co-exist for downlink communication. The high directionality of light rays in small cells, such as Pico and Atto cells, can offer a very high signal to noise and interference ratio (SINR) at high data rates. Consideration is given in this work to visible light communication links which utilise four wavelengths per access point (red, green, yellow and blue) for Pico and Atto cells systems, while the Micro cell system uses an infrared (IR) transmitter. Two 10-user scenarios are considered in this work. All users in both scenarios achieve a high optical channel bandwidth beyond 7.8 GHz. In addition, all users in the two scenarios achieve high SINR beyond the threshold (15.6 dB) needed for 10 -9 on off keying (OOK) bit error rate at a data rate of 7.1 Gbps. |
الرابط: | |
المؤتمر (14): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Impact of User Distribution on Optical Wireless Systems |
ملخص المشاركة: |
In this paper, we investigate the impact of user distribution on resource allocation in visible light communication (VLC) systems, using a wavelength division multiple access (WDMA) scheme. Two different room layouts are examined in this study. Three 10-user scenarios are considered, while an optical angle diversity receiver (ADR) with four faces is used. A mixed-integer linear programming (MILP) model is utilized to identify the optimum wavelengths and access point (AP) allocation in each scenario. The results show that a change in user distribution can affect the level of channel bandwidth and SINR. However, a uniform distribution of users in the room can provide a higher channel bandwidth as well as high SINR above the threshold (15.6 dB) for all users compared to clustered users, which is a scenario that has the lowest SINR with supported data rate above 3.2 Gbps. |
الرابط: | |
المؤتمر (15): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Beam Blockage in Optical Wireless Systems |
ملخص المشاركة: |
In this paper, we use the percentage blockage as a metric when an opaque disc obstructs the Line-of-Sight link from the access point to the receiver in an optical wireless indoor communication system. The effect of the different parameters of the obstructing object are studied, these are the radius, the height, and the horizontal distance from the receiver in the positive y direction. The percentage of blocked room locations to the total number of room locations when varying the disc parameters is studied assuming a single serving link. It was found that depending on the dimensions of the obstructing object and the distance from the receiver in addition to which access point is serving the user, that blockage can vary between 0% up to 100%. Furthermore, the service received by a user, in terms of beam blockage depends on the access point they are connected to. The resulting fairness challenges will be addressed in resource allocation optimization in future work. |
الرابط: | |
المؤتمر (16): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Effect of Receiver Orientation on Resource Allocation in Optical Wireless Systems |
ملخص المشاركة: |
Optical wireless communication (OWC) systems have been the subject of a significant amount of interest as they can be used in sixth generation (6G) wireless communication to provide high data rates and support multiple users simultaneously. This paper investigates the impact of receiver orientation on resource allocation in optical wireless systems, using a wavelength division multiple access (WDMA) scheme. Three different systems that have different receiver orientations are examined in this work. Each of these systems considers 8 simultaneous users in two scenarios. WDMA is utilised to support multiple users and is based on four wavelengths offered by Red, Yellow, Green and Blue (RYGB) LDs for each AP. An angle diversity receiver (ADR) is used in each system with different orientations. The optimised resource allocations in terms of wavelengths and access point (AP) is obtained by using a mixed-integer linear programming (MILP) model. The channel bandwidth and SINR are determined in the two scenarios in all systems. The results show that a change in the orientation of the receiver can affect the level of channel bandwidth and SINR. However, SINRs in both scenarios for all users are above the threshold (15.6 dB). The SINR obtained can support data rate of 5.7 Gbps in both scenarios in all systems. |
الرابط: | |
المؤتمر (17): | |
عنوان المؤتمر: |
IEEE 22nd International Conference on Transparent Optical Networks (ICTON) |
تاريخ الإنعقاد: |
19-23 July 2020 |
مكان الإنعقاد: |
Bari, Italy |
طبيعة المشاركة: |
Paper presentation |
عنوان المشاركة: |
Shared Optical Wireless Cells for in-Cabin Aircraft Links |
ملخص المشاركة: |
The design of a wireless communication system that can support multiple users at high data rates inside an aircraft is a key requirement of aircraft manufacturers. This paper examines the design of an on-board visible light communication (VLC) system for transmitting data on board Boeing 747-400 aircraft. The reading light unit of each seat is utilised as an optical transmitter. A red, yellow, green, and blue (RYGB) laser diode (LD) is used in each reading light unit for transmitting data. An angle diversity receiver (ADR), which is an optical receiver that is composed of four branches (in this work), is evaluated. The signal-to-interference-plus-noise ratio (SINR) and data rate are determined. Three scenarios have been examined where, in the first scenario, one device is used, in the second scenario two devices are used and in the third scenario three devices are used by each passenger. The proposed system can offer high SINRs that support high data rates for each passenger by using simple on-off-keying (OOK). |
الرابط: | |
جوائز التكريم |
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الجائزة (1): | |
مسمى الجائزة: |
The GW Carter Prize |
الجهة المانحة: |
University of Leeds |
تاريخ الجائزة: |
01/07/2020 |
مجال التكريم: |
Prize awarded for writing the best research paper published during the preceding year in the school of Electronic and Electrical Engineering. |