Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)

1. Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs) Submission Title: [Suggestions to CWPAN from IEEE802.15.4c Study Group] Date Submitted: [March 2007] Source: [Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt] Company: [ZigBee Alliance, Freescale Semiconductor, Integration Associates, Atmel] Address: [11 Louis Road, Attleboro, MA 02703 USA; 2100 E. Elliot Rd, MD: EL542, Tempe, AZ 85284, USA; 16 - 18 West Street, Reigate, Surrey RH2 9BS, United Kingdom; Königsbrücker Strasse 61, 01099 Dresden, Germany] Voice:[1-781-929-4832, 1-480-413-5413,1-480-413-4441, +44 1737 227728, +49 351 6523436], E-Mail:[bheile@ieee.org, clinton.powell@freescale.com, kuor-hsin.chang@freescale.com, pbeecher@integration.com, michael.schmidt@hno.atmel.com] Re: [ IEEE 802.15.4c ] Abstract: [Document suggestions to the CWPAN standard so that harmonizing between CWPAN and IEEE802.15.4 standard can be achieved.] Purpose: [To encourage discussion.] 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. Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)

2. Motivation • Compatibility with 802.15.4 will result in more choices and lower cost. Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)

3. Suggestions to CWPAN in PHY • PN Code: • Suggested modifications: • Circular shift by 2 instead of by 1 • PN Code 8-15 are complex conjugate of PN Code 0-7 • Change the PN Code from floating-point numbers to binary numbers • The PN code should lead to a DC free signal. • Advantage • Harmonize the PN Code generating process between CWPAN and 802.15.4 so that it can share most of the PN code generation HW • The correlator structure could be shared between CWPAN and 802.15.4 • DC free signal offers simpler transceiver design. • Disadvantage: • The orthogonality of PN code under ideal condition is compromised. But this could be offset in implementation. Also, the orthogonality of the Chinese PN code is compromised under non-ideal channel condition anyway. Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)

4. Suggestions to CWPAN in PHY (cont’d.) • Mapping data to PN Code: • Suggested Change: • For preamble, SFD, data payload using the same mapping method. This can be feasible after PN code generation process in CWPAN is changed. • Modulation: • Suggested Changes: • From MPSK type to OQPSK type • Change the pulse shaping filter from raise-cosine to half-sine • Advantages: • Constant envelope modulation simplifies power amplifier design. • DAC is not required in the transmitter for OQPSK+half-sine. • At the receiver, the resolution requirements for ADC is relaxed. • Half-sine pulse shaping+OQPSK can achieve the spectral requirement yet with simpler implementation. Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)

5. MAC Questions / Comments / Clarifications • MAC layer differences - Document 06-403 • QoS: we understand this is no longer required, please confirm. • security procedure – is this compatible with 15.4-2006? • Distributed Contention Access Scheme - document 07-610 • Confirm that this can be implemented by the NHL? • Confirm that the necessary hooks are already provided by the 15.4-2006 MAC? • Clarification of non-persistent CSMA - document 07-609 • Step 4 of slides 8 and 9 shows BE incremented based on retries – is this correct? • slide 7 - What is the calculation? Which PIB parameters are adjusted? • slide 12 – please show values of relevant PIB parameters and their effect. • GTS enhancement – document 07-602 • Clarify applications and confirm that these applications cannot be implemented with current MAC/GTS. • Confirm interoperability with current superframe structure • Suggest new GTS command and GTS specification field rather than redefinition of existing command and spec field Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)

6. General Comment in MAC • If additional MAC functionality is required to support the additional features proposed in CWPAN (e.g. E-GTS), it is recommended that CWPAN specifies this functionality as optional and ensures that it is interoperable with 802.15.4-2006 MAC. • Motivation – implementers may wish to only implement 802.15.4-2006 MAC functionality, but still be compliant with CWPAN. Bob Heile, Clint Powell, Kuor-Hsin Chang, Phil Beecher, Michael Schmidt (ZigBee Alliance, Freescale, Integration, Atmel)