Millimeter Wave Communication in 5G Wireless Networks By: Niloofar - PowerPoint PPT Presentation

Millimeter Wave Communication in 5G Wireless Networks By: Niloofar Bahadori Advisors: Dr. J.C. Kelly, Dr. B Kelley

Outline • 5G communication Networks • Why we need to move to higher frequencies? • What are the characteristics of mmWave band communications? • What are the challenges in using mmWave? • What are the existing solutions? • Application of mmWave in 5G framework. • Future works

5G networks Source: Cisco Visual Networking Index (VNI) Mobile, 2016

5G networks Network Specification 5G 4G Peak Data Rate 10 Gb/s 100 Mb/s 10 Tb/s/k 𝑛 " 10 Gb/s/k 𝑛 " Mobile Data Volume E2E Latency 5 ms 25 ms Energy Efficiency 10% current consumption 1 M/k 𝑛 " 1 k/k 𝑛 " Number of Devices Mobility 500 km/h - Reliability 99.999% 99.99%

5G networks Carrie #1: 20 MHz Existing solutions to improve Carrie #2: 20 MHz network capacity: Carrie #3: 20 MHz Increase Available BW • 100 MHz Carrier Aggregation • Carrie #4: 20 MHz Cognitive Radio • Carrie #5: 20 MHz Spectrum Reuse • D2D Communication • Small Cell network • Increase Spectral Efficiency • Massive MIMO • Spectrum Sharing • Even though some of these techniques can boost performance significantly, there is no clear roadmap on how to achieve the so far defined 5G performance targets.

U.S. Frequency Allocation The Radio Spectrum AM Broadcast TV Broadcast Cellular Communication Wi-Fi Equivalent Spectrum UWB 3.1–10.6 GHz, high data rate in PAN LMDS 28 -30 GHz broadband, fixed wireless, point-to- multipoint for last mile application Source: U.S. Dept. of Commerce, NTIA Office of Spectrum Management

mmWave Communication • Microwave band is referred to as Sweet spot due to its favorable propagation characteristics • Low frequency bands have been almost used up • It is difficult to find sufficient frequency bands in the microwave range for 5G improvements • mmWave with high bandwidth can be a potential solution for 5G communication • However, wave propagation in mmWave band has specific characteristics that should be considered in design of network architecture 3 GHz 57-64 164-200 300 GHz Candidate Bands 27.5–28.35 31.225–31.3 54 GHz 99 GHz 99 GHz 29.1–29.25 71-76 Cellular communication 31.075–31.225 81-86 Oxygen molecule Absorption Water Absorption 31.0–31.075 92-95 Potential available bandwidth

mmWave Characteristics Atmospheric Absorption • Raindrops are roughly the same size as the radio wavelengths (millimeters) and therefore cause scattering of the radio signal • The rain attenuation and molecular absorption characteristics of mmWave propagation limit the range of mmWave communications The rain attenuation and atmospheric absorption do not create significant additional path loss for cell sizes on the order of 200 m. Source: E-band technology. E-band Communications. [Online]. Available: http://www.e-band.com/index.php?id=86.

mmWave Characteristics High Propagation Loss and Sensitivity to Blockage mmWave communication suffers from high propagation loss 𝑄𝑀 ∝ 𝑔 " • Electromagnetic waves have weak ability to diffract around obstacles with a • NLOS path size significantly larger than the wavelength For example, blockage by a human attenuate the link budget by 20-30 dB • Only LOS communication is efficient. • LOS path Oxygen Frequency PLE- LOS PLE- NLOS Rain Attenuation Absorption Band (GHz) @200 m (dB) @200 m (dB) 𝑒 28 1.8 ~ 1.9 4.5 ~ 4.6 0.9 0.04 𝐺 𝑒 = 𝑄𝑀(𝑒 , ) + 10𝑜𝑚𝑝𝑕 5, 𝑒 , 38 1.2 ~ 2 2.7 ~ 3.8 1.4 0.03 60 2.23 4.19 2 3.2 Path-loss Exponent (PLE) 73 2 2.45 ~ 2.69 2.4 0.09 NLOS suffer from high attenuation

mmWave Characteristics Directivity • To combat severe propagation loss, high gain, directional antennas are employed at both transmitter and receiver • Beamforming is a key enabling technology of mmWave communication • With a small wavelength, electronically steerable antenna arrays can be realized as patterns of metal on circuit board 5 mm Directional antenna 16 antennas High gain at one direction very low gain in all other directions Integrated Circuit Source: F. Gutierrez, S. Agarwal, K. Parrish, and T.S. Rappaport, “On-Chip Integrated Antenna Structures in CMOS for 60 GHz WPAN Systems,” IEEE Journal on Selected Areas in Communications, vol. 27, no. 8, October 2009, pp. 1367 – 1377.

mmWave Characteristics • Due to the size of antenna at mmWave, large array of antenna can be realized on both BS and device 256 or more antennas at • mmWave communication is inherently Base station Directional • The directivity of transmission enables concurrent transmissions with low multi user Large array at mobile interference. station, 4-32 antennas Challenges: • MIMO cause higher power consumption • Beamforming add overhead to system • To make the transmitter and receiver direct their beams towards each other, the procedure of beam training is needed.

mmWave Characteristics Blockage mmWave are highly sensitive to blockage, • Building blockage Coordinating B.S • Body blockage B.S • Hand Blockage Design requirements: • High density of infrastructure required to cover areas around Building buildings • Need rapid switching between LOS and NLOS paths B.S • Array diversity on the handset Solutions • Multiple path can be computed when one is blocked the remaining can be used. • adds the complexity and overhead of the beamforming process Switch between different mode of communication •

Applications Small-Cell Networks Device-to-Device Communication • Massive densification of small-cells has • Device to Device Communication which is been proposed to achieve the 10000 used to transfer data between devices fold increase in network capacity. Small- without using the main infrastructure is one cells deployed underlying the macrocells of the promising approaches in 5G networks as WLANs or WPANs are a promising • Less power consumption solution for the capacity enhancement • Spectral efficiency in the 5G cellular networks. • Increasing quality of link • Less power consumption With huge bandwidth, and low interference of mmWave band • Decreasing latency communication, can be used in • Decreasing number of users small-cell access and backhaul assigned to each BS networks, and direct • Improve network coverage area communication among devices Source Niu, Yong, et al. "A survey of millimeter wave communications (mmWave) for 5G: opportunities and challenges." Wireless Networks 21.8 (2015): 2657-2676 .

Summary C hallenges B enefits: • High propagation loss • Higher bandwidth • Absorption by rain and Oxygen molecule • Small wavelength • Blockage Sensitivity • A large array of antenna can be • Needs model for blockage realized in a small area • only LOS communication is efficient • Directivity Beamforming add overhead to system • • Less MUI ••More spectrum Spectrum ••Larger channel Ultra-fast Broadband Communication Large Array ••Reduce interference and Narrow ••Spectrum reuse Beam

Future Work • In our proposed system model, D2D communication is Small-cell BS underlying a enabled in a mmWave small-cell network. macrocell • Network exploit mmWave and microwave resource to overcome the uncertainty of the mmWave environment n application are caused by blockages. running simultaneously • Our goal is to maximize number of satisfied applications scheduled at both frequency bands, based on their context information • Application maximum tolerable Delay • Size of the Data • Channel State information mmWave • Probability of LOS communication in mmWave band Band We are looking to find optimal solution for the optimization problem. Microwav A proper method to capture the uncertainty in mmWave e Band LOS channel. One time slot