doc.: IEEE September, 2009

Transcription

1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Title: [Samsung/ETRI's EFC: HBC PHY proposal] Date Submitted: [24 September, 2009] Source: [Jahng Sun Park, SangYun Hwang, Hyunkuk Choi, Seong-Jun Song, SeokYong Lee, Chul-Jin Kim, EunTae Won Samsung Electronics] [Jung-hwan Hwang, Hyung-il Park, Tae-young Kang, Sung-weon Kang ETRI] Re: [Response to IEEE Call for Proposals] Abstract: [PHY proposal for Requirements] Purpose: [To be considered in IEEE ] Notice: This document has been prepared to assist the IEEE P It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor acknowledges and accepts that this contribution becomes the property of IEEE and may be made publicly available by P

2 Proposal Scope Data exchange for control,,p personal health care, entertainment, etc. Periodical data, random bursts, etc. Everyday operation environment: home, office, outdoors, etc. On-body to On-body (CM3) Devices should be on the body surface or near a person as long as the person can reach and make contact Data rate ranges up to 10 Mbps Low power consumption 2

3 Human Body Communication Features of HBC Allows quick and easy connection Intuitive Service,,Quick Setup, Easy Use Afford Privacy & Security Utilizes Direct Digital Signaling FSDT (Frequency Selective Digital Transmission) Easy to Implement Low Power Consumption Small Size 3

4 Properties of EFC Electric Field Communication Data transmitted by inducing electric-field and capacitive coupling on dielectric material Human body has about 300~500 times better permittivity than air Facilitates FSDT and enables HBC No Antenna, less complex Extremely low power consumption EFC Transmitter Dielectric Material (e.g., Air, Water, Body) EFC Receiver Mobile Device Mobile Device EFC E-Field EFC Electrode Electrode 4

5 System Block Diagram Data Modulation: FS-Spreader (Orthogonal Code + FSC) Scalable Data rate: Up to 10 Mbps Electrod de MCU EFC Tx 5 FS : Frequency Selective FSC : Frequency Shift Code

6 Packet Structure Consists of Preamble (PR), SFD (Start Frame Delimiter), and payload In a PHY payload (PSDU), MAC header, MAC payload, and FCS (Frame Check Sequence) are included PHY payload size: < 1 K octets PHY Payload PR1 PR2 PR3 PR4 SFD PHY Header MAC Header MAC Payload FCS 6

7 Signal Generation (1/4) Preamble Preamble symbol repeated 4 times 1 preamble length: 128-bit Gold sequence FSC FSC: Frequency Shift Code Repeated [0 1] Operation freq. = f CK Preamble Field PR1 PR2 PR3 PR4 1 Preamble Symbol Generation Preamble length Freq. Shift Coding FSC f CK Preamble Symbol Generation 128-bit Gold code FSC 4-chip Preamble 1 Symbol Length Preamble Length chip 2048 chip Gold Code (128 bits) 1/4 f CK XOR f CK Preamble Symbol 7

8 Signal Generation (2/4) Start Frame Delimiter (SFD) SFD field : 128-bit Gold sequence FSC + time offset(rate Indicator) FSC: Repeated [0 1] Operation freq. = f CK SFD Generation Freq. Shift Coding FSC f CK Gold Code (128 bits) Time Offset SFD XOR 1/4 f CK f Symbol CK 8

9 Signal Generation (3/4) PHY Header/PSDU Generation 1 symbol : 16-bit FSC FSC: Repeated [0 1] Operation freq. = f CK Signal bandwidth depends on data rate (C), symbol conversion rate (1/N), and dthe length of orthogonal code (2L) FS-Spreader (C) Data Rate S2P convertor (C/N) Symbol Rate r0 r1 r2 Oth Orthogonal lcoding (Walsh Modulation) (C 2 L )/N Chip Rate XOR f CK cps r15 FSC (f CK ) 9

10 Signal Generation (4/4) Pilot sequence use SFD sequence Used to compensate for clock drift Inserted periodically Indicated in PHY header PSDU Data Pilot Data Pilot Data CRC Pilot Info Field Insertion Period byte byte byte byte byte byte 110 No pilot insertion 10 in PHY Header

11 Rate Indicator (1/2) RI uses SFD to indicate data rate: 7 classes Both PHY header and PDSU transmitted at the same data rate Provides throughput efficiency, especially for high data rates Preamble SFD/RI Header PSDU T 1 T 2 T 7 RI Data Rate SFD/RI Toffset1 Toffset2 125kbps 250kbps Toffset1 SFD_Code Toffset3 500kbps Toffset2 SFD Code Toffset4 1Mbps SFD_Code garbage SFD code Toffset7 SFD_Code Toffset Toffset5 2Mbps Toffset6 Reserved Toffset7 Reserved 11

12 Rate Indicator (2/2) May also use the traditional method using Data Rate Field (DRF) in PHY header One method selected during initial handshaking of two devices Master device selects the desired method During handshaking, DRF method is used to indicate the data rate DRF Data Rate kbps kbps kbps 011 1Mbps 100 2Mbps 101 Reserved 110 Reserved 111 Reserved in PHY Header 12

13 Packet format Data Rate Pilot Info Sync Resv. D BAN ID Resv. PSDU Length (3 bits) (3 bits) (1 bit) (1 bit) (1 bit) (3 bits) (1 bit) MSB (3 bits) PSDU Length LSB (8 bits) CRC (8 bits) Preamble SFD/RI Header PSDU PR1 PR2 PR3 PR4 Data Pilot Data Pilot Data CRC T 1 T 2 T 7 SFD/RI Toffset1 Toffset2 SFD_Code SFD_Code garbage Toffset7 SFD_Code SFD code Toffset 13

14 Simulated AWGN Performance AWGN channel Simulated in MATLAB in case of two samples per chip Symbol sync. & frame sync. operations are considered 1 & 2 Mbps with 1Koctets payload acket Error Rate P 1 ESNR C /N Mbps 1Mbps

15 Link Budget Parameter Symbol Value Unit Data Rate R 2 Mb/s Average Tx Power (1) P TX -16 dbm Path Loss (2) P L 54 db Average Rx Power (P RX =P TX -P L ) P RX -70 dbm Rx Noise Figure NF 9 db Average Noise Power per bit (P N = log 10 (R)+NF) P N -102 dbm Minimum required E -6 b /N o for BER=10 E b /N o req 7 db Implementation Loss I L 3 db Link Margin (LM=P RX -P N -E b /N o req -I L ) LM 22 db Minimum Rx Sensitivity Level (S RX =P RX -LM) S RX -92 dbm (1) Voltage-mode transmission (2) Sec Body surface to body surface CM3 (Scenario S4 & S5) for MHz Channel Model for Body Area Network (BAN) [IEEE ] 15

16 Transmitter Low Power Architecture Implemented with only digital circuits and share one electrode with receiver Receiver No need for blocks related to RF carrier signals such as mixer or VCO MAC protocol Merged proposal being prepared 16

17 Contact Information Samsung Electronics Jahng Sun Park Sangyun Hwang g Hyunkuk Choi hyunkuk.choi@samsung.com Seong-Jun Song sj33.song@samsung.com SeokYong Lee seokyong.lee@samsung.com Chul-Jin Kim cjkim65@samsung.com EunTae Won etwon@samsung.com ETRI Jung-hwan Hwang jhhwang@etri.re.kr Hyung-il Park hipark@etri.re.kr Tae-young Kang tykang@etri.re.kr Sung-weon Kang kangsw@etri.re.kr 17