Cho and Kang Generalization of Random Jitter Beamforming

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Joon Ho Cho and Young Yun Kang Communication and Information Systems Lab. (CISL) Department of Electrical Engineering Pohang University of Science and Technology (POSTECH), Korea ETRI Jan. 11, 2013 POSTECH 1/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Outline • Review of Random Jitter Beamforming • Generalized Random Jitter Beamforming – Signal Model and Hardware Impairments – AOD Estimation without H/W Impairments – AOD Estimation with H/W Impairments • Periodic Beam Sweeping • Implementation Issues – POSTECH MIMO Testbed with Compu. Gen and Compu. Scope – Universal Software Radio Peripheral (USRP) – Sundance DSP/FPGA board • Conclusion POSTECH 2/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming [12 Kwak] B. Kwak, S. Kim, Y. Kim, and N. Song, “Random jitter beamforming for pointand-link communications, ” IEEE Statistical Signal Processing Workshop (SSP), 2012. POSTECH 3/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming POSTECH 4/48

5/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming LOS implies frequency -flat channel. POSTECH

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming POSTECH 6/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming POSTECH 7/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Review of Random Jitter Beamforming POSTECH 8/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Outline • Review of Random Jitter Beamforming • Generalized Random Jitter Beamforming – Signal Model and Hardware Impairments – AOD Estimation without H/W Impairments – AOD Estimation with H/W Impairments • Periodic Beam Sweeping • Implementation Issues – POSTECH MIMO Testbed with Compu. Gen and Compu. Scope – Universal Software Radio Peripheral (USRP) – Sundance DSP/FPGA board • Conclusion POSTECH 9/48

10/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • Signal Model target device Tx 1 Tx 2 user device d Tx 3 Tx 4 – A sequence of beam vectors Tx 1 Tx 2 … Tx 3 Tx 4 1 POSTECH 2 3 … N Time or frequency : number of antennas

11/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming – Angle of Departure (AOD) Tx 1 user device Tx 2 Tx 3 Tx 4 – AOD vector POSTECH d target device

12/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming – Hardware impairments: Tx 1 w 1 BB/IF signal RF chain w 2 w 3 Tx 2 d Tx 3 Tx 4 w 4 • Gain vector and gain matrix: unknown deterministic complex number multiplied at each antenna output , POSTECH target device

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • Antenna coupling matrix: an example • Received signal: POSTECH 13/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • Signal model: where , POSTECH 14/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • Without Hardware Impairments: – Signal received by a device at AOD unknown observation known (to be designed ) known function – Sufficient statistic when POSTECH white noise is invertible 15/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • Without Hardware Impairments: – Sufficient statistic with whitened noise – Maximum likelihood estimation of POSTECH 16/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Generalized Random Jitter Beamforming • With Hardware Impairments – Sufficient statistic when is invertible – Maximum likelihood estimation is impossible unless and are known. POSTECH 17/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Outline • Review of Random Jitter Beamforming • Generalized Random Jitter Beamforming – Signal Model and Hardware Impairments – AOD Estimation without H/W Impairments – AOD Estimation with H/W Impairments • Periodic Beam Sweeping • Implementation Issues – POSTECH MIMO Testbed with Compu. Gen and Compu. Scope – Universal Software Radio Peripheral (USRP) – Sundance DSP/FPGA board • Conclusion POSTECH 18/48

19/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Periodic Beam Sweeping • Oscillating Electric Fan oscillating electric fan POSTECH time

20/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Periodic Beam Sweeping • Periodic Beam Sweeping Beam direction time POSTECH

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Outline • Review of Random Jitter Beamforming • Generalized Random Jitter Beamforming – Signal Model and Hardware Impairments – AOD Estimation without H/W Impairments – AOD Estimation with H/W Impairments • Periodic Beam Sweeping • Implementation Issues – POSTECH MIMO Testbed with Compu. Gen and Compu. Scope – Universal Software Radio Peripheral (USRP) – Sundance DSP/FPGA board • Conclusion POSTECH 21/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues • POSTECH MIMO testbed Antenna array Transmitter Receiver Industrial PCs RF chain boxes Signal generators <4 X 4 MIMO testbed antenna array> POSTECH 22/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Hardware specifications Number of transmit antennas up to 4 Number of receive antennas up to 8 Transmit antenna spacing 6. 3 cm to 50. 5 cm (3. 15 cm step) Receive antenna spacing 6. 3 cm to 50. 5 cm (3. 15 cm step) Center frequency up to 3. 2 GHz Bandwidth up to 30 MHz Transmit power up to 25 d. Bm/antenna Arbitrary IF waveform generator (DAC) Resolution: 12 bits Conversion rate: 300 MS/s, 150 MS/s, 75 MS/s, and external clock Memory size: 1 MS/channel IF signal acquisition board (ADC) Resolution: 12 bits Conversion rate: 200 MS/s, … , 50 k. S/s, and external clock Memory size: 512 MS/channel POSTECH 23/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Hardware settings Number of transmit antennas 4 Number of receive antennas 4 Transmit antenna spacing 0. 5 λ (≈6. 3 cm) Receive antenna spacing 0. 5 λ (≈6. 3 cm) Center frequency 2. 3765 GHz (λ≈12. 6 cm) IF center frequency 70 MHz Bandwidth 20 MHz Transmit power up to 20 d. Bm/antenna Arbitrary IF waveform generator (DAC) Resolution: 12 bits Conversion rate: 300 MS/s IF signal acquisition board (ADC) Resolution: 12 bits Conversion rate: 200 MS/s POSTECH 24/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Block diagram of MIMO testbed POSTECH 25/48

26/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Arbitrary IF waveform generator- Gage’s Compu. Gen 4300 – – Conversion rates: 300 MS/s, 150 MS/s, 75 MS/s, and external clock Internal clock accuracy: 20 ppm Resolution: 12 bits Memory size: 1 MS/channel (conversion rate가 300 MS/s일 때 3 ms 동안 신호 발생 가능) Ext. clock Ext. trigger Analog out out 1 2 3 4 Output marker <Industrial PC에 장착된 CG 4300> POSTECH <Connectors for CG 4300>

27/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • IF signal acquisition board - Gage’s Compu. Scope 12400 – – Sampling rates: 200 MS/s, 100 MS/s, 50 k. S/s, and external clock Internal clock accuracy: 25 ppm Resolution: 12 bits Memory size: 512 MS/channel (sampling rate가 200 MS/s일 때 2. 5 s 동안 신호 저장 가능) Slave Master Channel 1 Channel 3 Channel 2 Channel 4 Ext. clock Ext. trigger Clock out Trigger out <Industrial PC에 장착된 CS 12400> POSTECH Master Slave <Connectors for CS 12400>

28/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • RF chain boxes • • • 300 W power supply 내장 Mini-circuits사의 power amplifier, LNA, mixer, power splitter ASB 사의 PA, LNA, SAWNICS사의 RF SAW filter Mixer SAW 1 PA 1 SAW 2 PA 3 ch 4 ch 3 SAW 3 ch 2 ch 1 LO PLL SAW 2 Mixer SAW 1 LNA 2 ch 4 ch 3 ch 2 ch 1 LNA 1 LO PLL <Transmitter RF chain> POSTECH <Receiver RF chain>

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues 29/48 POSTECH MIMO Testbed • Antenna array (1/3) Unicorn사의 WLAN용 안테나 (OSI-05 A) Antenna spacing을 조절할 수 있는 antenna mount • • Frequency range 2. 4~2. 5 GHz Impedance 50 Ω VSWR 1. 92 max. Return loss -10 d. B max. Electrical wave ½λ dipole Gain 5 d. Bi Polarization Linear vertical Radiation pattern Omni-directional Max. power 30 d. Bm Connector SMA POSTECH <Vertical and horizontal polarization>

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues 30/48 POSTECH MIMO Testbed • Antenna array (2/3) Antenna coupling effects must be carefully taken into account. <Theoretical radiation pattern> <Measurement results of far-field radiation pattern > POSTECH

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Antenna array (3/3) • Antenna spacing: 6. 3 cm to 50. 5 cm (3. 15 cm step) <Antenna spacing: 6. 3 cm (0. 5λ when the center frequency is 2. 3765 GHz> POSTECH <Antenna spacing: 50. 5 cm (8λ when the center frequency is 2. 3765 GHz> 31/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Power characteristic of transmitter RF chain • Transmission power: up to 25 d. Bm CG 4300 POSTECH 32/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues 33/48 POSTECH MIMO Testbed • Gain and noise characteristic of receiver RF chain • Total noise figure: 0. 814 d. B • Total receiver gain: 35. 5 d. B • Noise power at mixer output: -62. 46 d. Bm POSTECH

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Outdoor 채널 측정을 위한 무선국허가 • 허가유효기간: 2007년10월 26일 부터~ • 주파수대역: 2. 363 GHz~2. 390 GHz (27 MHz) • 최대 송신 파워: 30 d. Bm <2. 3~2. 4 GHz 대역의 주파수 분배> POSTECH 34/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • 하드웨어 구축비용 POSTECH 35/48

36/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Testbed의 hardware 구성 • Digital-to-analog converter (DAC) – Compu. Gen / USRP 2 / Sundance board • Analog-to-digital converter (ADC) – Compu. Scope / USRP 2 / Sundance board • RF chain – – Up-conversion mixer RF surface acoustic wave (SAW) filter Power amplifier Low noise amplifier • Antennas – Omnidirectional dipole / patch POSTECH - USRP 2와 sundance board는 RF daughter board가 있음. - Compugen: transmitter - USRP 2 and sundance board: transceiver

37/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • USRP 2 (Universal Software Radio Peripheral 2) – ADC: 14 bit, 100 MS/s – DAC: 16 bit, 400 MS/s TX Ext. clock RX MIMO expansion <Connectors for USRP 2> POSTECH RF board <RF daughterboard>

38/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • USRP 2 (Universal Software Radio Peripheral 2) before sync. after sync. Synchronization 관련 프로 그램이 최근(2012. 11)에 제공됨. <N 200/N 210 2 X 2 design> POSTECH after sync. and phase compensation

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • USRP 2 (Universal Software Radio Peripheral 2) http: //www. ettus. com/ <4 X 4 MIMO configuration> POSTECH <4 X 4 MIMO configuration> 39/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues 40/48 POSTECH MIMO Testbed • Sundance SMT 8096 board – DSP/FPGA development platform • ADC: 14 bit, 105 MS/s • DAC: 16 bit, 500 MS/s FPGA 2 <Sundance SMT 8096 board> POSTECH <Architecture of SMT 8096 system>

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Sundance SMT 8096 board – RF daughterboard <Dual MIMO RF transceiver, 2. 4~2. 5 GHz and 5. 15~5. 875 GHz> POSTECH 41/48

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Sundance SMT 8096 board RF Chain Box Signal Generator Tx Antennas Processing PC with DSP/FPGA board Rx Antenna <Testbed of full-duplex amplify-and-forward relay> POSTECH 42/48

43/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Comparison of DAC boards Number of channels Conversion rate Resolution Memory size Internal clock accuracy Software cf. CG 8152: 8 ch. , 150 MS/s CG 4302 USRP 2 SMT 8096 4 (확장가능) 1 (확장가능) 2 (확장가능) 300 MS/s 400 MS/s 500 MS/s 12 bits 16 bits 1 MS/ch - - 20 ppm (VCXO) 2. 5 ppm (TCXO) 20 ppm (VCXO) MATLAB SDK Python C, VHDL done complicated easy Online processing X O O Development time very short longer than CG long Price 1, 200 만원 300 만원 2, 000 만원 Price for 4 channel 1, 200 만원 2, 500 만원 Synchronization POSTECH

44/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Comparison of ADC boards Number of channels Conversion rate Resolution Memory size Internal clock accuracy Software Multi-channel digital oscilloscope로 대체가능 CS 12400 USRP 2 SMT 8096 2 (확장가능) 1 (확장가능) 200 MS/s 105 MS/s 12 bits 16 bits 512 MS/ch - - 25 ppm (VCXO) 2. 5 ppm (TCXO) 20 ppm (VCXO) MATLAB SDK Python C, VHDL done complicated easy Online processing X O O Development time very short longer than CG long Price 2, 250 만원 300 만원 2, 000 만원 Price for 4 channel 4, 500 만원 1, 200 만원 2, 500 만원 Synchronization POSTECH

45/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues POSTECH MIMO Testbed • Development history of POSTECH MIMO testbed 2009. 05~2009. 12 ETRI 위탁과제 수행 2008. 06~2008. 11 ETRI 위탁과제 수행 USRP Sundance board Compu. Gen 2005 2006 2007 2008 2009 2010 2011 2012 2013 POSTECH year

Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Conclusion (1/3) • RJBF is generalized to the problem of designing a sequence of beam vectors. • For this generalized RJBF (G-RJBF), a statistical observation model is proposed that well separates the effects of the sequence of beam vectors, the angle of departure (AOD), and the hardware impairments. • The problem of the maximum likelihood estimation of the angle of departure is well-posed without the hardware impairments, while becomes ill-posed with the impairments. • To resolve the ill-posedness of the G-RJBF, we propose to use the periodic beam sweeping of which idea is motivated by the oscillating electric fan. • A tactically designed sweeping pattern enables a rough self -calibration that can turn the problem no longer ill-posed POSTECH 46/48

47/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Conclusion (2/3) • For the DAC, if an online demonstration is not necessary, Gage’s Compu. Gen (CG 4302 for 4 ch. , CG 8152 for 8 ch. ) can be a good choice because it does not suffer from the synchronization issue, and also can shorten the development time. online DAC offline POSTECH Single antenna USRP Multiple antennas Sundance SMT 8096 Single antenna USRP Multiple antennas CG 4300

48/48 Cho and Kang: Generalization of Random Jitter Beamforming and Its Implementation Issues Conclusion (3/3) • For the ADC, USRP is adequate for online demonstration with single or two receive antenna. online ADC offline POSTECH Single antenna USRP Multiple antennas Sundance SMT 8096 Single antenna USRP, digital scilloscope Multiple antennas CS 12400