Positioning with 5G mmWave Massi sive-MIMO Systems Henk Wymeersch - PowerPoint PPT Presentation

Positioning with 5G mmWave Massi sive-MIMO Systems Henk Wymeersch Gonzalo Seco-Granados Department of Electrical Engineering Department of Telecommunications Chalmers University of Technology Universitat Autonoma de Barcelona Gothenburg, Sweden Bellaterra, Spain https://goo.gl/KbrQEF https://spcomnav.uab.cat/~gseco email: henkw@chalmers.se email: gonzalo.seco@uab.cat With help from Arash Shahmansoori, Zohair Abu Shaban, Nil Garcia, Gabriel Garcia, Mike Koivisto, and others. Summer School on 5G V2X Communications, June 11 th , 2018 1

Main idea a of radio-base ased posi sitioning • Waveform conveys information about geometry • Different measurements can be taken – Signal strength: path loss vs fingerprinting – Time: TOA, TDOA, RTT – Angle: AOA, AOD – Frequency (Doppler): FOA • Main resources: delay resolution (bandwidth th), angle resolution (ante tenna elements ts), frequency resolution (time), interference mitigation (SNR) Summer School on 5G V2X Communications, June 11 th , 2018 2

Outline • 5G positioning: 5 selling points • 5G positioning: performance bounds • 5G positioning: algorithms • Conclusions • References Summer School on 5G V2X Communications, June 11 th , 2018 3

Radio-base sed positioning Two-way ranging cost and uplink TDOA ?? fingerprinting UWB downlink TOA uplink WiFi TDOA GPS Uplink Cell ID 5G potential 4G 3G 2G 1 cm 1m accuracy 10 cm 10m 100m Summer School on 5G V2X Communications, June 11 th , 2018 4

Radio-base sed positioning Summer School on 5G V2X Communications, June 11 th , 2018 5

What do we mean by 5G? image: image: Qualcomm University of Bristol Large antenna arrays Large bandwidths Directional transmission Higher carrier frequencies image: image: Ericsson YouTube Device-to-device Network densification communication Summer School on 5G V2X Communications, June 11th, 2018 6

5 Selling points s for 5G positioning 1. High carrier frequencies 5G 2. Large bandwidths 3. Large number of antennas 4. D2D communication 5. Network densification Summer School on 5G V2X Communications, June 11 th , 2018 7

High carrier er frequenc encies es • Received power due to path loss, shadowing, multipath fading • Path loss: countered by array gains • Shadowing: severe penetration loss so no shadowing • Multipath fading: no diffraction, limited scattering and little reflection • Communication channel is dominated by LOS and a few location- dependent clusters Below 6 GHz: full matrix (i.i.d., Gaussian) Above 28 GHz: low-rank matrix Each “effective path” corresponds to cluster Sparse communication channel, related to the physical environment Summer School on 5G V2X Communications, June 11 th , 2018 8

Large e bandwidths 1. From Fisher information: large bandwidth leads to better delay (distance) estimation accuracy 2. More resolvable multipath components: two paths are resolvable when 2 GHz bandwidth 30 meter Meissner, Paul, et al. "Accurate and robust indoor localization systems using ultra- High degree of resolvability of multipath wideband signals." arXiv preprint arXiv:1304.7928 (2013). Summer School on 5G V2X Communications, June 11 th , 2018 9

Large e number er of antenn ennas as • From Fisher information – Large number of RX antennas: better AOA resolvability – Large number of TX antennas: smaller beamwidth, better AOD resolvability High degree of resolvability of angles Summer School on 5G V2X Communications, June 11 th , 2018 10

D2D communicat ation • 5G will have sidelinks • Measurements between devices • Can improve location accuracy and coverage CCDF Error [m] Cooperative positioning based on D2D measurements Wymeersch, Henk, Jaime Lien, and Moe Z. Win. Summer School on 5G V2X Communications, June 11 th , 2018 11 "Cooperative localization in wireless networks." Proceedings of the IEEE 97.2 (2009): 427-450.

Network densi sificat ation • Many access nodes, which could be location references • High chance of LOS at short distances • LOS link most useful for positioning LOS link generally available for positioning http://www.5gworkshops.com/5G_Channel_Mod Summer School on 5G V2X Communications, June 11 th , 2018 12 el_for_bands_up_to100_GHz(2015-12-6).pdf

Outline • 5G positioning: 5 selling points • 5G positioning: performance bounds • 5G positioning: algorithms • Conclusions • References Summer School on 5G V2X Communications, June 11 th , 2018 13

5G mmWave positioning: model with L clust sters Limited number of RF chains. Precoding matrix F and combining matrix W . Estimate position (and orientation) in the presence of unknown scatterer locations Summer School on 5G V2X Communications, June 11 th , 2018 14

Some e geomet etric intuition • Abstraction AOD = direction from BS • Downlink • Known BS position • Consider downlink transmission. TOA = range from BS estimate position orientation AOA, AOD no yes AOA, TOA no* no AOD,TOA yes no AOA,AOD,TOA yes yes *unless orientation is known Summer School on 5G V2X Communications, June 11 th , 2018 15

Performanc ance bounds • Received waveform • Channel parameters and location parameters • Virtual anchors have no physical meaning for scatterers • Parametrization can also be in terms of scatterers and points of incidence Summer School on 5G V2X Communications, June 11 th , 2018 16

Fisher er informat ation matrix of chan annel el param amet eter ers • Unknown parameter • Noise-free observation • FIM has entries L This part was available in delay domain 7 L real parameters Summer School on 5G V2X Communications, June 11 th , 2018 17

Fisher er informat ation matrix of chan annel el param amet eter ers • Each sub-block (e.g., , ) is Hadamard product Signal & Receiver Transmitter gain ⦿ ⦿ component component component Tends to diagonal when paths Tends to diagonal when paths have distinct delays (for large have distinct AOA signal bandwidth) (for large number of receive antenna) Tends to diagonal when paths have distinct AOD (for large number of transmit antennas), under full MIMO • Conclusion: each sub-block will be almost diagonal Summer School on 5G V2X Communications, June 11 th , 2018 18

Fisher er informat ation matrix of chan annel el param amet eter ers • Original FIM • Rearrange parameters Each path provides independent information Summer School on 5G V2X Communications, June 11th, 2018 19

Fisher er informat ation matrix in position space • Remove channel amplitude with Schur complement • Introduce parameter of interest • Determine FIM invert FIM can be nonsingular (Potential for SLAM) • Compute EFIM invert of position and orientation • From EFIM we compute PEB and OEB • EFIM can be expressed as sum over the paths Summer School on 5G V2X Communications, June 11 th , 2018 20

Uplink vs downlink Downlink Uplink Unknown Unknown orientation orientation Beam in known direction Beam in unknown direction Same FIM in channel space FIM in channel space Position relates to delay, AOD Position relates to delay, AOA FIM in location space FIM in location space Leads to different scaling: Different! Summer School on 5G V2X Communications, June 11th, 2018 21

Results • 3D scenario (unknown [position, azimuth, elevation]) • 12 x 12 arrays at TX and RX • 38 GHz carrier, 125 MHz bandwidth (beam squint ignored) • 1 mW transmit power, 16 training symbols • Single path and 4 path channel • No combining (W = I) downlink uplink Z. Abu-Shaban, Xiangyun Zhou, T. Abhayapala, G. Seco-Granados, H. Wymeersch, "Error Bounds for Uplink and Downlink 3D Localization in 5G mmWave Systems", IEEE Transactions on Wireless Communications, May 2018. Summer School on 5G V2X Communications, June 11th, 2018 22

Single e path (LOS) with 6 beam ams Orientation error bound [deg] Position error bound [m] • Beam centers marked with black circles. Summer School on 5G V2X Communications, June 11th, 2018 23

Four paths s (including LOS) with 6 beam ams Orientation error bound [deg] Position error bound [m] Scatterer locations Summer School on 5G V2X Communications, June 11th, 2018 24

Indep epend endent path assu sumption 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 0.05 0.1 0.15 0.2 0.25 0.3 Summer School on 5G V2X Communications, June 11th, 2018 25

Uplinks s vs downlink: : PEB (delay ay + AOD (DL) or AOA (UL) L)) Summer School on 5G V2X Communications, June 11th, 2018 26

Uplinks s vs downlink: : OEB (AOA and AOD) Summer School on 5G V2X Communications, June 11th, 2018 27

Impac act of more e recei eive e antenn ennas: as: PEB Uplink sensitive to orientation 𝑂 𝑈 = 144 Rx gain increases, DL is better UL is better but not the spatial diversity for the AOD. UL positioning takes advantage of AOA with number of receive antennas Summer School on 5G V2X Communications, June 11th, 2018 28