doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [PHY Layer Submission for c] Date Submitted: [7 May 2007] Source: [André Bourdoux, Stefaan Derore, Jimmy Nsenga, Wim Van Thillo - IMEC] Address [Kapeldreef 75, 3001 Leuven, Belgium] Voice:[ ], FAX: [ ], Re: [TG3c technical requirements] Abstract:[] Purpose:[Proposed PHY layer for IEEE c 60 GHz WPANs] 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

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 2 Introduction Proposal for the PHY layer of IEEE c in response to CFP 07/586r2. Targets the high data rates Requirements of TG3c ( ) –Up to 3 Gbps including overheads –3 channels channelization –Suitable for integration in full CMOS Carefull analysis to reduce 60 GHz front-end impact

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 3 Criteria for good Air Interface Low cost Low power consumption Modest FE requirements Low channel equalization complexity

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 4 What is not in this presentation/proposal ? MAC impact or modifications Preamble/pilot design Specific mapping and/or coding scheme (e.g. unequal error protection) for the support of video We concentrate on the careful selection of the modulation/equalization scheme towards low cost, low power consumption and easy system-on-a-chip implementation

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 5 Air interface selection Battery-powered terminal Power amplifier and DAC/ADC are critical power consumer (Quasi-)constant envelope modulations LOS or NLOS, directional or omni- directional antennas Low-to-high multipath propagation Optional CP for frequency domain equalization PSK-based:CP-M-PSK CPM-based:CP-GMSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 6 CPI:Cyclic Prefix Insertion CPR: Cyclic Prefix Removal SC:Single-carrier FDE: Frequency Domain Equalizer OFDM SC solution IFFT CPIChannel Transmitter Receiver CPRFFTFDEDemodulator CPIChannelCPRFFTFDEDemodulator IFFT CPIChannelCPRDemodulatorSingle-tap equalizer ChannelDemodulatorSingle-tap equalizer NLOS LOS - option 1 Receiver “decides” LOS - option 2 Transmitter “decides” OFDM / SC-FDE / SC

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 7 Cyclic prefix addition Complexity is negligible Requires buffering of small part of the payload data CP length is programmable (0, 1/32, 1/16, 1/8 and 1/4) Midamble for CP-GMSK ensures phase continuity Payload data N CP N CP N+1 Payload data N+1 Payload data N-1 For CP-M-PSK: CP N CP N+1 Payload data N+1 Payload data N-1 For CP-GMSK: Payload data N Midamble (4 bits)

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 8 M-PSK and CP-M-PSK Transmitter Coding & Mapping DAC Add CP 2 Pulse shaping filter

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 9 M-PSK and CP-M-PSK Receiver ADC Remove CP Digital filter 2 Single-tap time- domain equalizer Freq-domain equalizer (FFT + equal. + IFFT) Demapping & Decoding

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 10 GMSK and CP-GMSK Transmitter Add CP and midamble 2 Freq. shaping filter 2πh2πh Phase Accum. Look-up table. Coding & Mapping DAC FM modulator Carrier frequency spacing: 2.3 GHz Can be approximated with QPSK like modulator

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 11 GMSK and CP-GMSK Receiver ADC Remove CP Matched filter (1 st Laurent pulse) Equal. Channel Decoding Filter 1 st Laurent Pulse FFTIFFT Midamble deletion Detector Soft / Hard

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 12 System parameters (1) CP-M-PSK –Block length: 512 symbols –CP length: 0, 16, 32, 64, 128 symbols –Maximum symbol rate: Gsymb/s –Block duration: ns (data) ns (CP) –TX filter roll-off: 0.2  BW = 2 GHz –Carrier spacing: (1+0.15)BW = 2.3 GHz –Bit rate (CP=25%, CR=3/4): BPSK: 1 Gbps QPSK: 2 Gbps 8-PSK: 3 Gbps

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 13 System parameters (2) CP-GMSK –Block length: 512 symbols –CP length: 0, 16, 32, 64, 128 symbols –Maximum symbol rate: Gsymb/s –Block duration: ns (data) ns (CP) –CPM pulse shape: Gaussian, length 3 –Carrier spacing: (1+0.15)BW = 2.3 GHz –Bit rate (CP=25%, CR=3/4): 1 Gbps

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 14 System parameters (3) Coded bit highest sample rate (3.333 Gsamples/s)

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 15 System parameters (4) - Scalability x 1/4

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 16 System parameters (5) – Frequency plan 2.3 GHz 575 MHz FS-A FS-B FS-C FS-D FS-B, FS-C and FS-D use same center frequencies FS-B, FS-C and FS-D can exploit flat portion of spectrum  diversity gain Simple synthesizer design

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 17 PSDs

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 18 PSD of M-PSK before PA Carrier frequency spacing: 2.3 GHz

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 19 PSD of M-PSK after PA Carrier frequency spacing: 2.3 GHz

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 20 PSD of GMSK (before/after PA) Carrier frequency spacing: 2.3 GHz

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 21 BER and PER performances

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 22 Modeled non-idealities (combined) PA: modified Rapp model –AM-AM: p = 1.1, G = 16 (12 dB) –AM-PM: q = 4.5, A = -885, B = ADC: –Resolution: 5 bits ENOB for M-PSK 4 bits ENOB for GMSK –Clipping level: 2xV rms Phase noise: –-87 dBc/Hz –- 20 dB/dec from 1 MHz –-140 dBc/Hz floor Δf (Hz) -87 dBc/Hz -140 dBc/Hz -20 dB/decade PSD (dBc/Hz) 1 MHz

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 23 Uncoded BER Performances Ideal case –CM13 – Single-tap time-domain equalizer (quasi LOS) –CM13 – Frequency-domain equalizer –CM23 – Frequency-domain equalizer –CM31 – Frequency-domain equalizer Combined non-idealities (PA + ADC + Phase noise (with tracking)) –CM13 – Single-tap time-domain equalizer (quasi LOS) –CM13 – Frequency-domain equalizer –CM23 – Frequency-domain equalizer –CM31 – Frequency-domain equalizer

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 24 Uncoded BER, ideal front-end

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 25 Uncoded BER, non-ideal front-end (PA, ADC and PN)

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 26 GMSK and CP-GMSK Sensitivity to non-idealities

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 27 BPSK and CP-BPSK Sensitivity to non-idealities

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 28 QPSK and CP-QPSK Sensitivity to non-idealities

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 29 8-PSK and CP-8-PSK Sensitivity to non-idealities

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 30 Coded BER/PER Performances Ideal case –CM13 – Single-tap time-domain equalizer (quasi LOS) –CM13 – Frequency-domain equalizer –CM23 – Frequency-domain equalizer –CM31 – Frequency-domain equalizer Combined non-idealities (PA + ADC + Phase noise (with tracking)) –CM13 – Single-tap time-domain equalizer (quasi LOS) –CM13 – Frequency-domain equalizer –CM23 – Frequency-domain equalizer –CM31 – Frequency-domain equalizer

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 31 Coded BER, ideal front-end

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 32 Coded BER, non-ideal front-end (PA, ADC and PN)

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 33 Coded PER, ideal front-end PER = 0.08

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 34 Coded PER, non-ideal front-end (PA, ADC and PN) PER = 0.08

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 35 Link budget, Sensitivity

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 36 Example link budget - BPSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 37 Example link budget - QPSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 38 Example link budget – 8-PSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 39 Range for different modes / antenna gains

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 40 Sensitivity for all modes, all channels

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 41 Individual non-idealities Modeled for CM13-LOS and CM23 Non-idealities: –PA –ADC –Phase noise compensated –“similar signal” in adjacent bands

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 42 PA effect CM23 LOS CM23 LOS 5 dB back-off is enough 3 dB back-off is acceptable CPM is unaffected

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 43 Effect of Phase noise CM23 LOS CM23 LOS CM23 LOS CM23 LOS -85 dBc/Hz is enough -87 dBc/Hz preferred for 8-PSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 44 Effect of Adjacent channel interference CM23 LOS CM23 LOS CM23 LOS +35 dB ACI is ok for most cases +30 dB for 8-PSK

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 45 Effect of ADC (4 bits) CM23 LOS CM23 LOS CM23 LOS

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 46 Effect of ADC (5 bits) CM23 LOS CM23 LOS CM23 LOS

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 47 Effect of ADC (3 bits) CM23 LOS For CPM and BPSK, 3 bits is ok For QPSK 4 bits is ok For 8-PSK, 5 bits is needed in multipath CM23 LOS

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 48 Impact of ADC on SC and OFDM Baseband sample rate = Gsps for the 3 modes SC-8PSK: 3 Gbits/s OFDM-8PSK: 2.4 Gbits/s OFDM-16QAM: 3.2 Gbits/s

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 49 Impact of PA on SC and OFDM Baseband sample rate = Gsps for the 3 modes SC-8PSK: 3 Gbits/s OFDM-8PSK: 2.4 Gbits/s OFDM-16QAM: 3.2 Gbits/s

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 50 Manufacturability

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 51 Zero-IF Transceiver

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 52 Analog Transceiver power consumption 45 nm CMOS process (External PA in other technology) Transceiver for (CP-)M-PSK and CP-GMSK 10 dBm output

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 53 Analog Transceiver power consumption 45 nm CMOS process Transceiver for (CP-)GMSK 4dBm output

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 54 Digital Receivers power consumption 45 nm CMOS process (channel estimation, synchronization not included)

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 55 Conclusion (1) Single carrier modulation can flexibly cope with LOS and non-LOS channels Avoids PAPR problem of OFDM  low cost, low power ADC and PA CPM (GMSK) is overall winner in LOS case (ADC 3 bits, 0 dB back-off) CPM is easily combined in DSP architecture M-PSK modes provide higher rates and multipath resistance with FDE

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 56 Conclusion Single-carrier approach is easily upgradable to higher constellations (QAM) Two classes of devices possible: –For LOS scenarios (simple receiver) –For NLOS scenarios (frequency domain equalizer) Easy manufacturability in cheap 45 nm CMOS processes

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 57 Back-up Slides

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 58 CPM parameters reminder log 2 M bits/symbol Pulse shape and length (rect, raised cos, gaussian, …) [Anderson, “Digital Phase Modulation”, 1986, Springer (Plenum Press)]

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 59 Achieving spectral efficiency with CPM 3COS,M=4,h=0.25 Good spectral performance 3COS,M=2,h=0.5 Low complexity 3COS,M=4,h=0.5 Good error performance

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 60 OFDM vs SC

doc.: IEEE c Submission 7 May 2007 André Bourdoux, IMECSlide 61 Double CP and FFT length for CM31