1. Submission Title: [OQPSK proposal for Chinese band]
July 2007
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [OQPSK proposal for Chinese band]
Date Submitted: [19−July−2007]
Source: [Michael Schmidt, Frank Poegel], Company: [Atmel]
Address: [Koenigsbruecker Str. 61, Dresden, Germany]
Voice:[ , ], FAX: [ , ]
E−Mail:
Re: [ c]
Abstract: [Discussion of filtering options for OQPSK to fulfill Chinese PSD requirements]
Purpose: [To encourage discussion in c]
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
Michael Schmidt and Frank Poegel (Atmel)

2. PHY proposal for 779…787MHz band
July 2007
PHY proposal for 779…787MHz band
The preferred choice is OQPSK modulation since it is easy to implement and is already part of the IEEE PHY
Chinese regulatory rules (see doc. IEEE c) specify a limit of -36 dBm (100 kHz RBW, RMS detector) at non specified distance from carrier
Targeting reduced side lobes implies that half-sine shaping might not be appropriate.
Options for pulse shaping:
Raised cosine (RC) shaping with roll-off factor R (OQPSK-RC-R)
Half-sine shaping + raised cosine shaping with roll-off factor R (OQPSK-SIN-RC-R)
Michael Schmidt and Frank Poegel (Atmel)

3. OQPSK proposal for 779…787MHz band
July 2007
OQPSK proposal for 779…787MHz band
Power spectra:
Ideal shaping filter
Random chip sequence
100 kHz resolution band width
0 dBm TX-power
Michael Schmidt and Frank Poegel (Atmel)

4. OQPSK proposal for 779…787MHz band, cont’d
July 2007
OQPSK proposal for 779…787MHz band, cont’d
Constellation chart (RC-pulse shaping):
Michael Schmidt and Frank Poegel (Atmel)

5. OQPSK proposal for 779…787MHz band, cont’d
July 2007
OQPSK proposal for 779…787MHz band, cont’d
Constellation chart (SIN-RC-pulse shaping):
Michael Schmidt and Frank Poegel (Atmel)

6. OQPSK proposal for 779…787MHz band, cont’d
July 2007
OQPSK proposal for 779…787MHz band, cont’d
EVM [%]
Crest factor [dB]
OQPSK-SIN
OQPSK-RC-0.5
0 (Nyquist)
1.0
OQPSK-RC-0.8
OQPSK-RC-1.0
1.25
OQPSK-SIN-RC-0.2 28
1.6
OQPSK-SIN-RC-0.5 30
1.1
OQPSK-SIN-RC-0.8 33
0.9
OQPSK-SIN-RC-1.0 35
0.6
Michael Schmidt and Frank Poegel (Atmel)

7. OQPSK proposal for 779…787MHz band, summary
July 2007
OQPSK proposal for 779…787MHz band, summary
Regulatory rules for China may require reduced side lobes: -36 non specified distance from carrier
SIN-RC shaping is not recommended w.r.t. EVM < 35%
RC-filtering reduces side lobes but increases the crest factor
Roll-off factor should be close to 1 in order to simplify a discrete time implementation
Robust non-coherent detection of OQPSK-RC can be achieved with well-known differential MSK-type detectors with no loss in performance, i.e. performance is similar to OQPSK 900 MHz
Michael Schmidt and Frank Poegel (Atmel)