doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 1 Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Modulation and Coding Scheme for a] Date Submitted: [3 March, 2003] Source: [ Francois Chin, Madhukumar, Xiaoming Peng, Sivanand ] Company [Institiute for Infocomm Reseaerch (Singapore)] Address [] Voice:[], FAX: [], Abstract:[] Purpose:[Provide background information and analysis regarding how modulation and coding schemes can be employed and how they perform in UWB channels] 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 /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 2 Outline Proposed use of UWB band Proposed Modulation and Coding Scheme System performance

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 3 Proposed use of UWB band Proposed Plan for Operating Frequency Bands 15 frequency sub-bands (500MHz each) within 3.1 – 10.6 GHz bands Centre frequency of sub- bands = (k-1)*0.5 GHz Merits Different frequency channels (consisting disjoint set of sub-bands) are allocated to simultaneous operating piconets Adjacent channel (consisting disjoint set of sub-bands) interference is suppressed to certain extend by receiver sub-band circuitry Coexistence with IEEE a is ensured as sub-bands centred at 5.35GHz or 5.85 GHz can be avoided, leaving others for 4 simultaneous operating piconets

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 4 Frequency sub-band scanning When a device is scanning to start a piconet, it should scan 15 frequency sub-bands (500MHz each) within 3.1 – 10.6 GHz to reduce the probability of selecting a occupied sub-band The device should rate the sub-bands based on an estimate of the amount of traffic and the power level in each sub-band The device then chooses those sub-bands that has traffic or/and power levels that is below a specific threshold

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 5 Key features of PHY proposal Modulation format and coding schemes As proposed in – device shall, at a minimum, support QPSK modulation QPSK & QAM modulator – to produce baseband signal that will excite the transmit circuitry to launch a pulse in one of the proposed frequency sub-band Fast switching reference PLL, switching at Pulse Repetition Frequency (PRF), together with quadrature mixer for frequency translation, to translate each pulse to and from its designated frequency sub-band Multiple PRFs are chosen to allow ‘grading’ of devices and to avoid intersymbol interference

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 6 Transmit Signals Consecutive pulses are transmitted over different sub-bands at a rate of PRF f0f0 f1f1 f2f2 f3f3 f4f4 f5f5 f6f6 f7f7 PRF = 250 MHz

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 7 Proposed Modulation, Coding, PRF, Payload Bit Rates & Data Throughput Modulation Type CodingPRF 62.5MHz125MHz250MHz QPSK8-state TCM62.5Mbps** (55Mbps) 125Mbps (110Mbps) 250Mbps (200Mbps) DQPSK (Base Mod.) None125Mbps (110Mbps) 250Mbps (200Mbps) 500Mbps (350Mbps) 16-QAM8-state TCM **Payload Rb (min PHY-SAP Data Tput) 375Mbps (300Mbps) 750Mbps (480Mbps) 32-QAM8-state TCM500Mbps (350Mbps) 1000Mbps (600Mbps) 64-QAM8-state TCM312.5Mbps (200Mbps) 625Mbps (400Mbps) 1250Mbps (700Mbps)

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 8 PRF / Symbol Transmission Rate Multiple Pulse Repetition Frequencies (62.5/125/250 MHz) provides scalability to –Power consumption –Payload bit rate –PHY-SAP data throughput Low target PHY-SAP data throughput, payload bit rate and low basic bit rate (for preamble, PHY/MAC header) that is associated to low PRF ensures low power consumption level If a device supports a PRF, it should also support all lower PRF PRF should remains within a frame transmission

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 9 Base Modulation Scheme & Basic Bit Rate Uncoded DQPSK is used as the base modulation scheme for Preamble, PHY header and MAC header uncoded DQPSK (Basic Modulation ) PRF 62.5MHz125MHz250MHz Basic Bit Rate125Mbps250Mbps500Mbps

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 10 PHY Frame Format Almost identical to that in Modulation Type CodingPRF 62.5MHz125MHz250MHz QPSK8-state TCM62.5Mbps** (55Mbps) 125Mbps (110Mbps) 250Mbps (200Mbps) DQPSK (Base Mod.) None125Mbps (110Mbps) 250Mbps (200Mbps) 500Mbps (350Mbps) 16-QAM8-state TCM **Payload Rb (min PHY-SAP Data Tput) 375Mbps (300Mbps) 750Mbps (480Mbps) 32-QAM8-state TCM500Mbps (350Mbps) 1000Mbps (600Mbps) 64-QAM8-state TCM312.5Mbps (200Mbps) 625Mbps (400Mbps) 1250Mbps (700Mbps)

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 11 Multiple Bit Stream Encoder or Single Bit Stream Encoder?

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 12 Multiple Bit Stream Encoder or Single Bit Stream Encoder? Single bit stream encoder should be chosen as it can better correct uniformly-spaced symbol errors due to ‘poor’ performance in particular sub-band

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 13 PHY-SAP Payload Bit Rate & Data Throughput Packet overhead parameters for data throughput comparison

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 14 PHY-SAP Payload Bit Rate & Data Throughput for 62.5 MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 15 PHY-SAP Payload Bit Rate & Data Throughput for 125 MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 16 PHY-SAP Payload Bit Rate & Data Throughput for 250MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 17 System Performance

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 18 Sub-band Receiver Each device should have same number of parallel subband receivers as number of sub- bands employed Each sub-band receiver oversamples at 500MHz and combines the oversamples with RAKE or channel equalisers

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 19 Eb/No in AWGN & UWB Channel in OverSampling RAKE Receiver Modulation Type CodingEb/No for PER ~ 8% in AWGN (1024-octet packet) Eb/No for PER ~ 8% in OverSamp UWB Channels using 8 sub- band (1024-octet packet) QPSK8-state TCM6 dB~9 dB + (Energy loss in corr CMs) QPSK (Base Mod.) None10 dB~13 dB + (Energy loss in corr CMs) 16-QAM8-state TCM9 dB~12 dB + (Energy loss in corr CMs) 32-QAM8-state TCM11 dB~14 dB + (Energy loss in corr CMs) 64-QAM8-state TCM13 dB~16 dB + (Energy loss in corr CMs)

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 20 Channel Energy Loss in diff. CMs Due to staggered frequency-time transmission, energy outside receive timing window (of duration equals to 1/PRF) of the current sub-band is lost Channel Energy Loss (dB) PRF 31.25MHz62.5 MHz125MHz250MHz CM (1.3) (1.5) (1.7) Norminal value Mean (std-dev) CM (1.4) (1.5) (1.6) (1.7) CM (1.1) (1.1) (1.2) (1.6) CM (1.1) (1.1) (1.2) (1.3)

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 21 RF Receiver Noise Figure -90° I Q LNA BPF Quad. Mixer LPF LO Antenna VGA Gain Control BPFLNA and VGAQuad. MixerLPF Gain (dB) N.F. (dB) Cascaded (dB) With fast switching PLL

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 22 Link Budget for 62.5 MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 23 Link Budget for 125MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 24 Link Budget for 250 MHz PRF

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 25 PRF and simultaneously operating piconets 1/PRF * (total #sub-bands per piconet) should be more than Channel delay spread so that a simple RAKE (vector RAKE) can be used Normally, when a another piconet get associated, operating PRF is reduced too (Data throughput is reduced alongside) to maintain PER performance

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 26 RAKE or Channel Equaliser? Adaptive Equaliser, on the other hand, can be employed to equalise ISI in the event of simultaneously operating piconets, when the total sub-band per piconet reduces. This will generally result in maintaining the data throughput, as Eb/No is maintained This implies, when a another piconet get associated, operating PRF can be retained (Data throughput remains alongside), while PER performance is maintained

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 27 Merits of Proposed Modulation and Coding Schemes for Alt-PHY Modulation and coding schemes are –Of low complexity –Well proven and mature technology –Free of proprietary or patented IP

doc.: IEEE /107r0 Submission March 2003 Francois Chin, Madhukumar, Xiaoming Peng, Sivanand, I 2 RSlide 28 Merits of Proposed Alt-PHY