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Systems-on-Chip Lab True-time-delay based MIMO System and Testbed for Low Latency Wideband Beam and Interference Management in Millimeter-wave Networks

True-time-delay based MIMO System and Testbed for Low Latency Wideband Beam and Interference Management in Millimeter-wave Networks

True-Time-Delay based MIMO System and Testbed for Low-Latency Wideband Beam and Interference Management in Millimeter Wave Networks

Project Description

Given the shortage of spectrum below 6GHz, millimeter wave (mmW) frequencies have played an important role in the emerging 5G networks and this trend is expected to continue in the next generations. Due to unfavorable propagation conditions and attenuation at high frequencies, mmW networks require the densification of base stations and radios equipped with a large number of antennas to compensate path loss via directional gain using narrow beams. The cost and power consumption of radios with antenna arrays present a significant challenge, and their architecture is of fundamental importance and influence on the entire networking stack. State-of-the-art approaches based on phased antenna array architecture are faced with several fundamental problems when radio bandwidth and the number of antennas increases including prohibitive latency in initial connectivity and link management, distortion in the directionality of the beams, reduced beamforming gain, and ability to suppress the interference in dense deployments. This project aims to develop and demonstrate a novel adaptive true-time-delay (TTD) based array for wideband mmW networks and overcome challenges of phased antenna arrays. The approach involves co-design and optimization of tunable radio frequency (RF) circuits, antenna array system, signal processing, and network protocols for low latency access, wideband beamforming gain, and interference management.

The research work will pursue four key thrusts: Thrust 1 will develop TTD array-based fast beam training and spatial interference detection and estimation for mmW networks with large modulated bandwidth. The objective is to reduce the overhead in initial access due to beam training by exploiting frequency-dependent antenna weight vectors in TTD arrays through signal processing and develop a low latency protocol design for simultaneous beam training and interference estimation in dense mmW networks. Thrust 2 will focus on the data communication design using TTD arrays to facilitate multiple-input multiple-output (MIMO) multiplexing and suppress interference from co-channel base stations and users. The main challenge is to achieve high beamforming gain over a wide modulated bandwidth together with effective nulling of wideband interferers. Thrust 3 will develop an experimental testbed for the evaluation of signal processing algorithms and protocols from Thrusts 1 and 2. It will involve the integration of widely reconfigurable delay compensating circuits and custom mmW front-end at 28GHz into a 16-element TTD antenna array. Thrust 4 will experimentally validate TTD array-based beam training, squint-free wideband beamforming and interference nulling, and wideband MIMO communications using the testbed developed in Thrust 3.

Acknowledgements

This project is supported by National Science Foundation award (#1955672/1955306). Lead PI on this project is Prof. Danijela Cabric (UCLA) with Profs. Subhanshu Gupta (WSU PI) and Deukhyoun Heo (WSU Co-PI). Partial support has been provided by the Center for Analog and Digital Integrated Circuits (CDADIC).

People – Faculty
People – Current Students
People – Former Students
  • Veljko Boljanovic, Ph.D., University of California Los Angeles (now Design Engineer at Qualcomm)
  • Erfan Ghaderi, Ph.D. , Washington State University (now Design Engineer at Intel)
  • Chung-Ching Lin, Ph.D., Washington State University (now Design Engineer at Qualcomm)
  • Chase Puglisi, M.S., Washington State University (now Design Engineer at Texas Instruments)
  • Han Yan, Ph.D., University of California Los Angeles (now Design Engineer at Apple)
Research Activities

The project goals are focused on novel designs of beam training and beam forming in wideband millimeter-wave networks by leveraging frequency-dependent beam steering/combining of true-time-delay arrays and recent advances in their implementation. Specifically, the project aims to address the high-latency beam training, wideband interference cancellation, and multiplexing of wideband signals with true time delay architectures. The work can be broadly divided into three parts: 1) system and algorithm design for all considered problems in true-time-delay based millimeter-wave networks; 2) design and implementation of a testbed with true-time-delay array architectures; 3) experimental demonstration and validation of proposed solutions.

Related Publications/Products
  1. V. Boljanovic and D. Cabric, “Joint Millimeter-Wave AoD and AoA Estimation Using one OFDM Symbol and Frequency-Dependent Beams,” IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Rhodes Island, Greece, 2023, pp. 1-5, doi: 10.1109/ICASSP49357.2023.10094643.
  2. V. Boljanovic and D. Cabric, “Joint Single-Shot AoD/AoA Estimation in mmW Systems and Analysis under Hardware Impairments”, IEEE International Conference on Communications (ICC),  Rome, Italy, May 2023.
  3. Veljko Boljanovic, Shamik Sarkar, and Danijela Cabric. 2022. Millimeter-wave user association and low-interference beam scheduling: invited paper. In Proceedings of the 6th ACM Workshop on Millimeter-Wave and Terahertz Networks and Sensing Systems (mmNets ’22). Association for Computing Machinery, New York, NY, USA, 7–12. https://doi.org/10.1145/3555077.3556471
    V. Boljanovic, ” Millimeter-Wave Channel Estimation with True-Time-Delay Arrays and Its Use for Network Performance Optimization “, https://escholarship.org/content/qt3c4174wp/qt3c4174wp_noSplash_8a1dcc09157362bcb5063461596ea861.pdf Ph.D. thesis, UCLA, December 2022.
  4. C. -C. Lin et al., “Wideband Beamforming With Rainbow Beam Training Using Reconfigurable True-Time-Delay Arrays for Millimeter-Wave Wireless [Feature],” in IEEE Circuits and Systems Magazine, vol. 22, no. 4, pp. 6-25, Fourthquarter 2022, doi: 10.1109/MCAS.2022.3214408.
  5. Soumen Mohapatra, Chung-Ching Lin, Subhanshu Gupta, Deukhyoun Heo, “Low Power Process and Temperature Invariant Constant Slope-and-Swing Ramp-based Phase Interpolator”, to be published in IEEE Journal of Solid-State Circuits, pp. 1-10, 2023.
  6. Chung-Ching Lin, Qiuyan Xu, Huan Hu, and Subhanshu Gupta, “Design Considerations of Time-interleaved Discrete-time Beamformers Toward Wideband Communications”, accepted for publication to IEEE Transactions of Circuits and Systems – II: Express Briefs (TCAS-II), pp. 1-5, 2023. (PDF)
  7. Qiuyan Xu, Chung-Ching Lin, Huan Hu, and Subhanshu Gupta, “Common-Mode Drift Resilient Ring-Oscillator-Based Time-Domain Filter for Next-Generation Wireless”, accepted for publication to IEEE Midwest Symposium on Circuits and Systems (MWSCAS) , pp. 1-4, 2023.
  8. Veljko Boljanovic and Danijela Cabric, “Millimeter-Wave Wideband Channel Estimation Using Analog True-Time-Delay Array Under Hardware Impairments”, Journal of Signal Processing Systems, May 2022.
  9. R. Li, H. Yan and D. Cabric, “Rainbow-Link: Beam-Alignment-Free and Grant-Free mmW Multiple Access Using True-Time-Delay Array,” IEEE Journal on Selected Areas in Communications, vol. 40, no. 5, pp. 1692-1705, May 2022, doi: 10.1109/JSAC.2022.3143261. (PDF)
  10. Qiuyan Xu, Aditya wadaskar*, Chung-Ching Lin, Han Yan, Veljko Boljanovic, Subhanshu Gupta, Danijela Cabric, “A Switching-less True-time-delay based Beam Probing Approach for Ultra-Low Latency Wireless Communications: System Analysis and Demonstration”, accepted for publication to IEEE Transactions of Circuits and Systems – II: Express Briefs (TCAS-II), pp. 1-5, 2022. (* – Equally-credited authors). (PDF)
  11. Chung-Ching Lin, Chase Puglisi, Veljko Boljanovic, Han Yan, Erfan Ghaderi, Jayce Gaddis, Qiuyan Xu, Sreeni Poolakkal, Danijela Cabric, Subhanshu Gupta, “Multi-Mode Spatial Signal Processor with Rainbow-like Fast Beam Training and Wideband Communications using True-Time-Delay Arrays,” IEEE Journal of Solid-State Circuits (JSSC), pp. 1-12, 2022.(PDF) 
  12. Chung-Ching Lin and Subhanshu Gupta, “Investigation and Implementations of Time interleaved Discrete-time Beamforming System for Wideband Communications,” SRC TechCon 2022, to be presented in Sept, 2022. (PDF)
  13. Soumen Mohapatra, Chung-Ching Lin, Mohammad Chahardori, Erfan Ghaderi, Aminul Hoque, Subhanshu Gupta, and Deuk Heo “A 345μW 1GHz Process and Temperature Invariant Constant Slope-and-Swing Ramp-based 7-bit Phase Interpolator for True-Time-Delay Spatial Signal Processors,” IEEE Radio Frequency Integrated Circuits Symposium (RFIC), to be presented in June, 2022. (PDF)
  14. Chung-Ching Lin, Veljko Boljanovic, Han Yan, Erfan Ghaderi, Mohammad Ali Mokri, Jayce Jeron Gaddis, Aditya Wadaskar, Chase Puglisi, Soumen Mohapatra, Qiuyan Xu, Sreeni Poolakkal, Deukhyoun Heo, Subhanshu Gupta, Danijela Cabric, “Wideband Beamforming with Rainbow Beam Training using Reconfigurable True-Time-Delay Arrays for Millimeter-Wave Wireless,” to be published at IEEE Circuits and Systems Magazine (CAS MAG), 2022. (PDF)
  15.  Aditya Wadaskar, Veljko Boljanovic, Han Yan, and Danijela Cabric, “3D Rainbow Beam Design for Fast Beam Training with True-Time-Delay Arrays in Wideband Millimeter-Wave Systems,”  55th Asilomar Conference on Signals, Systems, and Computers, 2021, pp. 85-92 (PDF)
  16. Chung-Ching Lin, Chase Puglisi, Veljko Boljanovic, Soumen Mohapatra, Han Yan, Erfan Ghaderi, Deukhyoun Heo, Danijela Cabric, Subhanshu Gupta, “A 4-Element 800MHz-BW 29mW True-Time-Delay Spatial Signal Processor Enabling Fast Beam-Training with Data Communications,” accepted to the IEEE European Solid-State Circuits Conference (ESSCIRC), to be presented in Sept., 2021. (PDF)
  17. Veljko Boljanovic and Danijela Cabric, “Compressive Estimation of Wideband mmW   Channel using Analog True-Time-Delay Array,” accepted to the IEEE International Workshop on Signal Processing Systems (SiPS), to be presented in Oct. 2021.
  18. Chung-Ching Lin, Chase Puglisi, Veljko Boljanovic, Soumen Mohapatra, Han Yan, Erfan Ghaderi, Deukhyoun Heo, Danijela Cabric, Subhanshu Gupta, “A 4-Element 800MHz-BW 29mW True-Time-Delay Spatial Signal Processor Enabling Fast Beam-Training with Data Communications,” accepted to the IEEE European Solid-State Circuits Conference (ESSCIRC), to be presented in Sept., 2021.  (PDF)
  19. Veljko Boljanovic, Han Yan, Chung-Ching Lin, Soumen Mohapatra, Deuk Heo, Subhanshu Gupta, Danijela Cabric, “Fast Beam Training with True-Time-Delay Arrays in Wideband Millimeter-Wave Systems,” IEEE Transactions of Circuits and Systems – I: Regular Papers (TCAS-I), vol. 68, no. 4, pp. 1727-1739, April 2021. (PDF)
  20. Veljko Boljanovic, Han Yan, Erfan Ghaderi, Deuk Heo, Subhanshu Gupta, Danijela Cabric, “Design of Millimeter-Wave Single-Shot Beam Training for True-Time-Delay Array,” 20th IEEE Signal Processing Advances in Wireless Communications (SPAWC), May 19–23 2020, Atlanta, GA, pp. 1–6. (PDF)
  21. P. Agarwal, M. Chahardori, and D. Heo, “A New Boosted Active-Capacitor with Negative-Gm for Wide Tuning Range VCOs” , IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 68, no. 3, pp. 1080-1090, March 2021. 
  22. Erfan Ghaderi, Ajith S. Ramani, Arya A. Rahimi, Deuk Heo, Sudip Shekhar and Subhanshu Gupta, “A 4-Element Wide Modulated Bandwidth MIMO Receiver with >35 dB Interference Cancellation,” IEEE Transactions of Microwave Theory and Techniques (TMTT), vol. 68, no. 9, pp. 3930-3941, Sept. 2020. (PDF)
  23. Han Yan, Veljko Boljanovic, and Danijela Cabric, “Wideband Millimeter-Wave Beam Training with True-Time-Delay Array Architecture,” Asilomar Conference on Signals, Systems, and Computers, Nov. 2019.
Educational activities
  • New course modules have been introduced on discrete-time beamforming in advanced integrated circuit design (EE 596).
  • PIs have disbursed research outcomes to semiconductor companies include Boeing Inc., Apple, Intel, Texas Instruments, Rohde & Schwarz, Analog Devices, Qualcomm, and Semiconductor Research Corporation.
  • The PI has included course modules on millimeter wave communications and array architectures for spatial signal processing including the True Time Delay arrays in graduate course ECE 233 Wireless Communications System Design at UCLA and EE 596 at WSU.
Outreach and other broader impact outcomes

The PIs have an active outreach program with wireless telecommunication industry and academia

  • D. Cabric, Invited speaker, “Wideband mm-Wave Beam Training with True-Time-Delay Array Architectures”, IEEE RFIC workshop on “Large-Scale Antenna Arrays: Circuits, Architectures, and Algorithms, June 2022.
  • D. Cabric, Distinguished Seminar Speaker, “Ultra-Low-Latency Millimeter Wave Networking usingTrue-Time-Delay Array Architecture”, North Carolina State University, Mar. 2022.
  • D. Cabric, Distinguished Seminar Speaker, “Exploiting Abundance Millimeter Wave Spectrum for Low Latency Communications and Massive Connectivity Beyond 5G”, Princeton, Feb. 2022.
  • D. Cabric, Invited Panelist, “Transcending layers: Crossing the divide between lower and upper layers”, NSF Networking and Telecommunication Systems (NeTS) Researchers, January 2022.
  • D. Cabric, Keynote speaker, “Ultra-Low-Latency Millimeter Wave Networking using True-Time-Delay Array Architecture”, IEEE Computing and Communication Workshop and Conference (CCWC), virtual, January 2022.
  • D. Cabric, Distinguished Seminar Speaker, “Exploiting Abundance Millimeter Wave Spectrum for Low Latency Communications and Massive Connectivity Beyond 5G”, UC Berkeley, Dec. 2021
  • S. Gupta, “Reimagining Millimeter-Wave Planar Antenna Arrays for Next-Generation Wireless” at Indian Institute of Technology, Madras, Chennai, India, July 2023.
  • S. Gupta, Workshop tutorial, “Recent Baseband Discrete-time Delay Compensation for Large Scale Antenna Arrays” for full-day workshop at IEEE Custom Integrated Circuits Conference (CICC), San Antonio, Texas, April 2023.
  • S. Gupta, Faculty talk, “Wideband True-time-delay Receivers”, Indian Institute of Technology, Bombay (IITB) and IIT Kharagpur (IITKGP), India, Oct. 2022.
  • S. Gupta, Chief Guest/Guest Lecture, “IoT and Communications for Next Generation Wireless” National Institute of Technology, Tiruchirapalli (NITT), India, Feb. 2022 (virtual).
  • S. Gupta, Research Colloquium, “Multi-Mode Spatial Signal Processors for Reliable mm-Wave Wireless”, University of Washington, Department of Electrical and Computer Engineering (ECE), Seattle, WA, Jan. 2022.
  • S. Gupta, Workshop Organizer, “Large-Scale Antenna Arrays for 6G and Beyond: Architectures, Algorithms, Circuits”, full-day workshop at IEEE Radio Frequency Integrated Symposium (RFIC), Denver, CO, June 2022.
  • S. Gupta, Invited Talk, “True-Time-Delay Arrays for Data Communications and Direction Finding”, Industry, Sept 2021.
  • S. Gupta, Visiting Academic at Amazon Project Kuiper FY 2022-23.
  • CDADIC, SRC (PIs Gupta and Heo)
  • DARPA ComSenter, CONIX, and NSF SpectrumX Alliance (Prof. Cabric).