doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Flexible DSSS Proposal for China Frequency Band] Date Submitted: [5 July, 2009] Source: [Y X Fu, J Shen, X Wang, Haituo Liu, L Li, Z Zhao, Z.F Zhao] Company [SIMIT, Vinno, JiaXing Wireless Sensor Networks Engineering Center, Huawei] Address [NO.865 Changning Road, Shanghai, 200050, China] Voice:[+86 21 6251 1070 ], FAX:[+86 21 6213 2314], E-Mail:[ fyx@mail.sim.ac.cn, jerryshen08@gmail.com, liang_1@yahoo.com ] Re: [IEEE 802.15.4g group] Abstract: According to the regular limitation of frequency in China Smart Grid. A proposal of Flexible DSSS PHY layer on 779-787MHz to meet the requirement and characteristic. Purpose: Presented to the 802.15.4g SUN Task Group for consideration Notice: This document has been prepared to assist the IEEE P802.15. 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 P802.15. FX. Fu, J.Shen Liang Li <author>, <company>

Flexible DSSS Proposal for China Frequency Band <month year> doc.: IEEE 802.15-<doc#> June. 2009 Flexible DSSS Proposal for China Frequency Band FX. Fu, J.Shen , Liang Li <author>, <company>

779-787MHz Regular Limit in China <month year> doc.: IEEE 802.15-<doc#> June. 2009 779-787MHz Regular Limit in China Max TX Power = 10mW (EIRP) No occupied bandwidth requirement Spurious emission is no larger than -36dBm FX. Fu, J.Shen <author>, <company>

Support the DSSS Modulation at 779-787MHz <month year> doc.: IEEE 802.15-<doc#> June. 2009 Support the DSSS Modulation at 779-787MHz 779-787MHz is officially assigned for Wireless Control Application (Ptx< 10mW) and adopted in CWPAN std and 15.4c Std. In CWPAN and 15.4c std, for DSSS modulation, the BW (channel) is defined as BW=2MHz. Support the DSSS modulation on 780MHz Bands for its tech advantages and it is widely adopted in WPAN, Zigbee and more applications. However, bandwidth of each channel may be modified for new spec FX. Fu, J.Shen <author>, <company>

Why Flexible DSSS Special circumstances Flexible DSSS Benefits P2P distance cover from 10m~1km Limited TX power : 10mW Flexible DSSS can get an additional trade-off process gain to meet both ends Flexible DSSS Benefits Adapt to transmitting circumstance easily Variable PN length M-ary spread spectrum Easy to schedule BW unchanged Robust Anti-multipath fading

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Channel spacing Eight channels are available across 780MHz band Independent channels are used to support simultaneous operation for at least 3 co-located orthogonal networks and avoid inner interferences of the network Independent channels provide more choice when there is a interference Fc = 779.5+k in megahertz, for k = 0,…7 FX. Fu, J.Shen <author>, <company>

General Description of the System <month year> doc.: IEEE 802.15-<doc#> June. 2009 General Description of the System Modulation O-QPSK or MPSK Spreading Spreading gain from 0~18dB Channel Coding and Interleave(option) To support the long frame requirements ½ rate convolution code CRC CRC-16 for short frame CRC-32 for long frame FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Flexible Spreading Spread SHR and PHR with the a fixed PN sequence set by the MAC(usually the largest one) Spread PPDU data with variable PN sequence, the pattern indicator of which is stated in PHR FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Flexible Spreading Normally, use 64 PN length as spreading factor at the preamble+SFD+PHR field FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Flexible Spreading Large gain at the SHR and PHR can make sure of the system synchronization protect the important field of SFD and PHR The same PN sequence at the preamble and SFD and PHR field to all the devices in a domain can be used as the fair judgment in measuring RSSI Inform the existence of a signal to all devices reduce the complexity of catch block design at the receiver FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Flexible Spreading On-time adjustment of spreading pattern by the indicator in PHR field can Choose the suitable pattern to transmit signals directly without handshake through the MAC Reduce the involvement of MAC in handling the adjustment of transmit signals Gain the benefit of the optimal energy efficient link margin given the environmental conditions encountered in Smart Metering deployments with less cost FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Spreading Mode Mode Chip rate (cps) Chips per Symbol Bits per Symbol Bit rate (bps) Gain(dB) Note 500k 1 16 4 125k 6.02 2 32 62.5k 9,03 3 31.25k 12.04 15.62k 15.05 5 64 7.81k 18.06 FX. Fu, J.Shen <author>, <company>

Spreading Code and Preamble Design <month year> doc.: IEEE 802.15-<doc#> June. 2009 Spreading Code and Preamble Design Spreading Code 16-ary PN codes defined in IEEE 802.15.4C for OQPSK and MPSK 32-ary PN codes defined in IEEE 802.15.4-2006 Preamble Design Preamble is mainly used to catch the frame, thus it should guarantee it could accumulate the higher SIR than all the PHY payload To the option PN code, which is too long, to reduce the complexity of catching filter design, different preamble can be taken FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Pulse Shape Filter Raised cosine pulse shape with roll-off factor of r = 0.8 Employed in 802.15.4c FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 PPDU Format Octets: variable 2 1 variable Bits: variable 16 7 4 3 Preamble SFD Frame Length Extended Length Upper Extended Address Pattern Indicator Parity Check PSDU Includes FCS SHR PHR PHY Payload The length of preamble is variable Frame Length + Extended Length + Upper Extended Address stand for the possible whole frame length required in the PAR Pattern Indicator indicates which PN code should be used PHY Payload Spread with the PN code indicated by indication factor FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 New PHY PIB attributes phyTransmitMode To inform Flexible DSSS transmit mode selection Type: Integer Value: 0-7 FX. Fu, J.Shen <author>, <company>

Support from Physical Layer Sum Up <month year> doc.: IEEE 802.15-<doc#> June. 2009 Support from Physical Layer Sum Up Frequency adjustment There are 8 channels under the adjustment of MAC, and MAC can assign the right channel to a device to make the network run more efficiency Different spreading pattern adjustment MAC can change spreading pattern through PHY PIB FX. Fu, J.Shen <author>, <company>

Support from Physical Layer Sum Up <month year> doc.: IEEE 802.15-<doc#> June. 2009 Support from Physical Layer Sum Up Channel Listening support The PN code is the same at the frame head, thus all the devices can hear it and get to know that a signal is to be transmitted, and the last time of the frame is also known The RSSI can be measured through the frame head, which is the same to all nodes FX. Fu, J.Shen <author>, <company>

Support from Physical Layer Sum Up <month year> doc.: IEEE 802.15-<doc#> June. 2009 Support from Physical Layer Sum Up Inner PN CSMA support When the longest PN code is applied, the phase shift can be used to support multi-user When a device has a data to send, while it heard the preamble of another device, it can carefully choose the phase shift and control its send power to send at almost the same time Be useful especially when the destination device is the same FX. Fu, J.Shen <author>, <company>

Consideration with Existing MAC (Beacon) <month year> doc.: IEEE 802.15-<doc#> June. 2009 Consideration with Existing MAC (Beacon) Slotted CAP: Since all the frame head use the same PN code, listening to the PN code of the frame head at the beginning of the slot will avoid the conflicts The device pair can judge which mode is best for transmission after the short conversation at CAP field, and they can keep the result for a period of a time (which could be set according to the mobility of the network). At CFP field, the device can use the judge result from the CAP field to transmit signals. FX. Fu, J.Shen <author>, <company>

Consideration with Existing MAC (Non-beacon) <month year> doc.: IEEE 802.15-<doc#> June. 2009 Consideration with Existing MAC (Non-beacon) To the non-beacon enable case, it is suggested that the PHY payload field use the same PN code as the preamble. If different PN code is used in preamble and the PHY payload field, the device should be able to detect all the PN code, or it should listen for quite a long time which could make sure the preamble should have appeared in case there is one Inner PN CSMA can be applied to expand the system capability FX. Fu, J.Shen <author>, <company>

doc.: IEEE 802.15-<doc#> <month year> doc.: IEEE 802.15-<doc#> June. 2009 Thank you FX. Fu, J.Shen <author>, <company>