Millimeter Wave: the future of commercial wireless systems

Transcription

1 Sildes are Robert W. Heath Jr Millimeter Wave: the future of commercial wireless systems Professor Robert W. Heath Jr. Wireless Networking and Communications Group Department of Electrical and Computer Engineering The University of Texas at Austin Also with MIMO Wireless Inc (see Thanks to the National Science Foundation Grant No. NSF-CCF , NSF-CCF , NSF- CCF , the Intel / Verizon 5G program, the U.S. Department of Transportation through the Data-Supported Transportation Operations and Planning (D-STOP) Tier 1 University Transportation Center, the the Texas Department of Transportation under Project , and gifts from Nokia, MERL, Huawei, and Toyota InfoTech.

2 New operational regimes for wireless Sildes are Robert W. Heath Jr Data rates Gb/s Mb/s kb/s Forbidden region Motivation for new 5G cellular technologies, but also applies to wireless LAN b/s ,000 Number of users Need new technology that can provide high data rates *Image modifed fromf. Bocardi, R. Heath, A. Lozano, T. Marzettaand P. Popovski, Five Disruptive Technology Directions for 5G, IEEE Commun. Mag.,

3 Wireless fundamentals Sildes are Robert W. Heath Jr Limited by the standard, amount of spectrum owned by the operator, finite supply per FCC MIMO spatial multiplexing gain requires multiple antennas and good propagation conditions, requires supporting more antennas in the standard rate per user = (bits per second) bandwidth Number of active users (devices) decreases with more frequency reuse, improve via smaller cells, sectoring, or multiuser MIMO X MIMO # of users X spectral efficiency Depends on signal power, noise power and interference power, improves with interference cancellation Bandwidth is the key to higher data rates

4 Why millimeter wave (mmwave)? Sildes are Robert W. Heath Jr Spectrum available Bandwidth per channel 33x 5-20x 800 MHz vs. 27 GHz Comparing cellular + WiFi below 6 GHz and likely bands from 28 GHz to 90 GHz 100 MHz vs. 500 MHz vs. 2 GHz Comparing cellular with carrier aggregation versus possible mmwave bandwiths at 30 GHz and 72 GHz carriers WiFi comparison Maximum bandwidth MIMO Claimed peak rates (downlink) Rate you might actually get IEEE ac 160 MHz Gbps 700 Mbps IEEE ay 4 GHz 2 24 Gbps TBD 4

5 X capacity improvement Example gains in application to 5G cellular % 38x 62x 28 sparse 28 dense 72 sparse 72 dense * Note the fine print about dense networks Baseline 2 GHz w/ Upper cmwave 28 GHz: 50 MHz BW 500 MHz (expect 10x) Sildes are Robert W. Heath Jr mmwave 72 GHz: 2 GHz (expect 40x) Surprise - mmwave gains are more than a spectrum multiplier! Average 58x 95x 28 sparse 28 dense 72 sparse 72 dense * T. Bai and R. W. Heath Jr., Coverage and rate analysis for millimeter wave cellular networks, IEEE Trans. Wireless Commun., Feb ** T. Bai, A. Alkhateeb, and R. W. Heath, Jr., ``Coverage and Capacity of Millimeter Wave Cellular Networks," IEEE Communications Magazine, Sept

6 Robert W. Heath Jr. Use of antennas at mmwave 6

7 Antenna arrays to provide enough aperture Sildes are Robert W. Heath Jr aperture at mmwave TX highly directive transmission aperture at a conventional frequency RX highly directive reception Directional transmission with large arrays provides necessary gain 7

8 The antenna arrays are small at mmwave Sildes are Robert W. Heath Jr antennas are about 10 mm (the large objects are antenna connectors, used only for prototyping) Samsung Galaxy S7* Base station may have 64 to 512 antennas Mockup of a Galaxy with mmwave** Mobile station may have 4 to 32 antennas * From ** W. Roh et al. "Millimeter-wave beamforming as an enabling technology for 5G cellular communications: theoretical feasibility and prototype results," in Communications Magazine, IEEE, vol.52, no.2, pp , February

9 Benefits of directional transmission Strong interference happens much less often 20 x gain Sildes are Robert W. Heath Jr Sidelobe interference is weaker rate multiplier Additional gain from less interference in the narrower beams Rate gain when only accounting for stronger signal 2 x gain pointy beam Interference reduction in mmwave gives even better rates fat beam 9

10 Robert W. Heath Jr. Rethinking and baseband 10

11 Sildes are Robert W. Heath Jr Design considerations for mmwave MIMO systems, circuits & devices?????? Nt? MIMO architectures implementing directional transmission are different at mmwave 11

12 MIMO system at < 6 GHz frequencies Sildes are Robert W. Heath Jr DAC 2 to 8 antennas ADC MIMO Precoding DAC Bandwidths of MHz ADC MIMO Combining Baseband and Precoding Equalization DAC ADC # antennas = # = # pairs ADCs Conventional MIMO heavily leverages digital signal processing 12

13 Power consumption impacts MIMO architecture Large antenna systems at mmwave High cost and power consumption of mmwave components Power at 60 GHz 1GHz BW 20mW LNA 40mW ADC 250 mw Baseband processing Baseband Precoding Freq. Band. N RX Power consumption 2.8 GHz 20 MHz mw 6 GHz 1 GHz 4 2 W!!!! LNA ADC Unlikely to dedicate a separate chain and ADC for each antenna * R. Méndez-Rial, C. Rusu, N. González-Prelcic, A. Alkhateeb and R. Heath Hybrid MIMO Architectures for MmWave Communications: Phase shifters or switches?, IEEE Access ** R. Heath, N. González-Prelcic, S. Rangan, W. Roh and A. Sayeed, An Overview of Signal Processing Techniques for Millimeter Wave MIMO Systems, IEEE JSTSP,

14 MIMO architectures at mmwave: analog beamforming Phase shifters apply for the entire band beamformer network of phase shifters Consumption in the phase shifter depends on the angle resolution combiner Baseband ain DAC H ain ADC Baseband Constant gain and quantized angles Limited to single stream and single user MIMO Phase shifters * J.Wang, Z. Lan, C. Pyo, T. Baykas, C. Sum, M. Rahman, J. Gao, R. Funada, F. Kojima, H. Harada et al., Beam codebook based beamforming protocol for multi-gbps millimeterwave WPAN systems, IEEE Journal on Selected Areas in Communications, vol. 27, no. 8, pp , ** S. Hur, T. Kim, D. Love, J. Krogmeier, T. Thomas, and A. Ghosh, Millimeter wave beamforming for wireless backhaul and access in small cell networks, IEEE Transactions oncommunications, vol. 61, no. 10, pp ,

15 MIMO architectures at mmwave: hybrid precoding Analog beamforming with multiple chains Number of DACs / ADCs is generally << # of antennas DAC 1-bit ADC 1-bit DAC ADC N s >= 1 Baseband Precoding 1-bit DAC ADC L t Precoding N t N r Combining L r 1-bit DAC ADC Baseband Combining F BB F W W BB N s >= 1 Combine analog and digital beamforming Flexible approach for multi-stream MIMO or multiuser MIMO at mmwave *Ahmed Alkhateeb, Jianhua Mo, Nuria González Prelcic and Robert W. Heath, Jr., ``MIMO Precoding and Combining Solutions for Millimeter Wave Systems,'' IEEE Communications Magazine, vol. 52, no. 12, , December

16 ` MIMO architectures at mmwave: combining with ` 1-bit ADCs Higher BB complexity Transmit Processing N t H N r Chai n 1-bit 1-bit ADC 1-bit ADC 10mW Baseband Precoding Processing 1 bit, 240 Gs/s much less at 4 Gs/s Ultra low power solution " Exploit sparsity ` using 1-bit CS to " estimate the channel With few bits 2b bits per complex dimension y Q phs ` vq With one sign bit p p ` `q q y sign phs ` vq threshold in real / imaginary *J. Mo, P. Schniter, N. G. Prelcic and R. W. Heath, Jr. Channel Estimation in Millimeter Wave MIMO Systems with One-Bit Quantization, Asilomar 2014 **C. Rusu, R. Mendez-Rial, N. Gonzalez-Prelcic and R. W. Heath, "Adaptive One-Bit Compressive Sensing with Application to Low-Precision Receivers at mmwave," 2015 IEEE Global Communications Conference (GLOBECOM), San Diego, CA, 2015, pp

17 Application areas for mmwave Robert W. Heath Jr. 17

18 WPAN at 60 GHz Multimedia streaming especially HDMI Dell Laptop * Peripheral connections Compliant products available Sony wearable HDTV * Kiosk data transfer Zyxel AeroBeam HDTV kit * Epson projector * Standard Bandwidth Rates Approval WirelessHD 2.16 GHz Gbps Jan WirelessHD GHz 4 x Gbps Jan Widely seen as the first 60 GHz consumer product * 18

19 WLAN at 60 GHz cable replacement In-room LAN Chipsets available and products are shipping Gbps peak throughputs Nitero chipset* Wilocity s chipset** Standard Bandwidth Rates Approval Date IEEE ad 2.16 GHz 6.76 Gbps Dec Tensorcom s chipset*** Next gen is currently in development (802.11ay) targeting 100 Gbps ** *** **** 19

20 Sildes are Robert W. Heath Jr Wearables at 60 GHz Reasonable isolation for lowend devices Connected person High data rates for high-end devices Wireless headset Device to track dog s activity Connected Augmented reality glasses pet Fitness trackers Smart watch Smart phone Likely realized using IEEE ad or WirelessHD at 60 GHz *A. Pyattaev, K. Johnsson, S. Andreev, and Y. Koucheryavy, Communication challenges in high-density deployments of wearable wireless devices, IEEE Wireless Communications, vol. 22, pp , February **K. Venugopal, M. Valenti, and R. W. Heath, Jr., `` Device-to-Device Millimeter Wave Communications: Interference, Coverage, Rate, and Finite Topologies,'' submitted to IEEE Trans. on Wireless, June 2015.Also on ArXiv. See related ITA version as well. 20

21 Sildes are Robert W. Heath Jr G cellular networks (28 GHz, 38GHz, 60GHz, E-Band, etc) Self-backhauled network mmwave sensing-bs Multiband connectivity mmwave relay mmwave backhaul mutiband BS Robert W. Heath Jr. 2 Many new components of 5G infrastructure

22 Connected cars Exchanging raw sensor data is possibe Sildes are Robert W. Heath Jr Joint communication and radar Vehicle driving cloud directional beamforming Enables high data rate infotainment applications V2V communication beams blockage V2I communication beam Sensing technologies can be used to help establish mmwave links MmWave is the only viable approach for high bandwidth connected vehicles* *Junil Choi, Nuria González-Prelcic, Robert Daniels, Chandra R. Bhat, and Robert W. Heath Jr, Millimeter Wave Vehicular Communication to Support Massive Sensing, to appear in IEEE Communications Magazine. 22

23 Robotics Large amount of sensors sending data to the central unit Videocameras 3D image sensor Sildes are Robert W. Heath Jr Cloud for robots IR camera Pressure sensor Inertial motion sensor Central unit sending sensing data to the operator Laser scanner Radar Sonar Tactile sensor Central unit Applications in drones and robots for industry, agriculture, security, surgery, 23

24 Robert W. Heath Jr. Millimeter wave is coming to a wireless system near you Check out research videos at goo.gl/yyx