Large Scale Antenna Systems Made Practical: Advanced Signal Processing for Compact Deployments [LSAS-SP]

Lead Research Organisation: Heriot-Watt University
Department Name: Sch of Engineering and Physical Science

Abstract

Abstracts are not currently available in GtR for all funded research. This is normally because the abstract was not required at the time of proposal submission, but may be because it included sensitive information such as personal details.
 
Description 1) Through the research funded on this grant, we developed the low-complexity direction estimation method which can be used in communication systems as well as radar systems, exploiting the compressive sensing. The principal of the compressive sensing is that the sparsity of a signal can be used to recover it from far fewer samples than required by the Shannon-Nyquist sampling theorem. This method will especially benefit in the large-scale antenna system, since the increase of the antenna elements leads to complexity in signal processing techniques. Moreover, we exploited the signal active (radio frequency (RF) chain) electronically steerable parasitic antenna (ESPAR) as a solution to interference mitigation using its beamforming capability. It is noted that the EPSAR antenna is a practical technique can be used for RF-chain reduction, which is critical for massive MIMO systems to reduce hardware cost and energy consumption. Further, to address the interference in multi-user MIMO systems, the channel state information at the transmitter (CSIT) is required; however, it is challenging to obtain a real-time perfect CSIT. The blind interference mitigation methods we developed do not require CSIT.

2) Developing new hybrid analog and digital beamforming for frequency selective channels: We proposed a low complexity and effective beamforming methods for frequency selective scenarios. Despite the simplicity of the methods, they achieve a comparable spectral efficiency compared to their digital beamformer counterpart. It is noted that our methods significantly reduces the computational complexity for massive MIMO systems and it improves the energy efficiency. In this research, we proposed new architectures for massive MIMO systems to reduce the cost and implementation complexity. The proposed methods rely on combination of switches, phase shifters and baseband processing. Our architectures and methods, not only reduce the cost and power consumption, they also reduce the computational complexity of the beamformers.

3)We proposed a novel approach to solve a challenging optimization problem (analogue-digital processing). Due to its nonconvex nature the reported works in the field often relied on computational demanding solutions, whose applicability can be questioned in practice. Moreover, they are often derived for either rich or poor scattering environments (which in turn depends on the operating frequency band), but not both. One of the main advantages of our proposed method, which has its roots in stochastic optimization, is that it can be used in environments with both rich and poor scattering characteristics. Additionally, the algorithm is quite fast and does not depend on the scattering; hence, the method is applicable to both sub-6 GHz (rich scattering) and millimetre wave (poor scattering) frequencies. The method can be widely adopted in hybrid transceiver design/optimization, due to its low complexity, performance and generality.

4) Asimilar approach was adopted for the 3D beamforming of hybrid transceivers using multi-active (RF chains) and multi-passive antenna arrays for ESPAR designs. A novel algorithm was derived and the study demonstrated that these types of transceivers can successfully emulate the (3D) beams of uniform rectangular arrays (URAs), while the number of active elements is reduced by 50%. As a result, the cost of each sensor can be significantly reduced, with no compromise in performance, which can have a huge impact in internet-of-things (IoT) or industrial applications, where the number deployed units is large.
Exploitation Route We will be presenting at conferences, workshops and to our industrial partners.
Sectors Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Education
 
Description We have worked on some projects with non-academic partners (DSTL, UK and European Space Agency (ESA)), where we applied some findings of this project in a different setting. However, the results were not directly applicable to the problem set.
First Year Of Impact 2021
Sector Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software)
Impact Types Policy & public services
 
Description 5G UK Mapping workshop held at Glasgow, Scotland
Geographic Reach Local/Municipal/Regional 
Policy Influence Type Contribution to a national consultation/review
 
Description 5G Rural-First: Rural Coverage and Dynamic Spectrum Access Testbed and Trial
Amount £4,300,000 (GBP)
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 04/2018 
End 07/2019
 
Description DSTL call for MASNET
Amount £60,000 (GBP)
Organisation Defence Science & Technology Laboratory (DSTL) 
Sector Public
Country United Kingdom
Start 01/2016 
End 12/2017
 
Description Thematic Partnership titled "Full Duplex and Cognitive Radio Architectures for Spectrally, Efficient Communications (FD-CR-ASEC)"
Amount £72,000 (GBP)
Organisation British Council 
Department British Council in India
Sector Public
Country India
Start 04/2017 
End 03/2019
 
Description Special Journal Issue organised in IEEE Journal of Selected Topics in Signal Processing on Introduction to the Issue on Hybrid Analog-Digital Signal Processing for Hardware-Efficient Large Scale Antenna Arrays ( Part I & Part II). 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact This special issue has been motivated by the recent increasing interest in: a) the practical challenges the deployment of large scale antenna systems (LSAS); b) the rising interest in the millimeter wave (mmWave) spectrum for 5G deployment which necessitates high-gain beamforming with low cost; c) the recent advances on analog-digital signal processing; and d) the ever-increasing interest in energy ef?cient communications. Accordingly, the aim of this Special Issue (SI) has been to gather the relevant contributions focusing on the practical challenges of hybrid analog-digital transmission as outlined above. We received a total of 59 submissions from researcher across the Globe of particularly high quality, spanning a broad range of topics. After a strict review process, we decided to accept 23 papers, which are published as two issues.
Year(s) Of Engagement Activity 2018
URL https://ieeexplore.ieee.org/abstract/document/8363116
 
Description Special Session "Hybrid Analog / Digital Signal Processing for Hardware-Efficient Large Scale Antenna Arrays" in the 25th European Signal Processing Conference (EUSIPCO), Kos, Greece, August 2017. 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact We organised a special session on "Hybrid Analog / Digital Signal Processing for Hardware-Efficient Large Scale Antenna Arrays" in the 25th European Signal Processing Conference (EUSIPCO), Kos, Greece, August 2017 which attracted many submissions in the area.
Year(s) Of Engagement Activity 2017
URL https://www.eusipco2017.org/special-sessions/
 
Description UK 5G Mapping Scotland Innovation Workshop held at Glasgow, Scotland in February 2018. 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Study participants or study members
Results and Impact The future goal of digitisation in Scotland is to create a 5G hub for ensuring that Scotland is in the forefront of 5G R&D, testing and deployment. Our research on cutting-edge 5G technologies - massive multiple-input multiple-output (MIMO) systems and non-orthogonal multiple access (NOMA) were presented at the 5G UK Mapping workshop held at Glasgow, Scotland in February 2018. The workshop had participants from leading industries such as CISCO, policy convenors from Digital Catapult, policy makers from Scottish Future Trust and academic representatives from University of Glasgow and West Scotland. The presentation was well received and there was unanimous support for our technical work. Our technical work was considered as one of the key innovations for realizing the 5G hub in Scotland. Further, the meeting concluded that rural areas in Scotland must require better connectivity and our objective is to fine tune our technical developments to achieve the goal of a well-connected 5G rural network in Scotland.
Year(s) Of Engagement Activity 2018
URL https://www.digitalcatapultcentre.org.uk/open-calls/5g-uk-mapping-innovation-workshops/