doc.: ieee 15-08-0797-00-004d submission november 2008 m. schmidt and f. poegel, atmelslide 1...
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November 2008
M. Schmidt and F. Poegel, AtmelSlide 1
doc.: IEEE 15-08-0797-00-004d
Submission
Project: IEEE P802.15 Working Group for Wireless Personal Area Project: IEEE P802.15 Working Group for Wireless Personal Area Networks (WPANs)Networks (WPANs)
Submission Title: Receiver Jamming Resistance for Japanese 950 MHz Low Power Active Radio Systems
Date Submitted: November 11th, 2008Source: Michael Schmidt and Frank Poegel, AtmelContact: Michael Schmidt, [email protected]: +49 351 6523 436Re: Abstract:Technical requirements on the receiver jamming resistance for 950 MHz
low power radio systems.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.
November 2008
M. Schmidt and F. Poegel, AtmelSlide 2
doc.: IEEE 15-08-0797-00-004d
Submission
Receiver Jamming Resistance for Japanese 950 MHz Low Power Active Radio Systems
Michael Schmidt and Frank Poegel
Atmel
November 2008
M. Schmidt and F. Poegel, AtmelSlide 3
doc.: IEEE 15-08-0797-00-004d
Submission
Problem
Requirements on the Receiver Jamming Resistance as specified in P802.15.4d/D2 are presumably too stringent.
November 2008
M. Schmidt and F. Poegel, AtmelSlide 4
doc.: IEEE 15-08-0797-00-004d
Submission
Alternate Channel Rejection
AAC
C
- 40 ppm
+ 40 ppm
30 dB
TX-F TX-F + 4 MHz (BPSK-915, O-QPSK-915)
AAC
C
- 20 ppm
+ 20 ppm
30 dB
TX-F TX-F + 1.2 MHz (BPSK - 950)TX-F + 0.8 MHz (GFSK - 950)
IEEE-802.15.4-2006 @ 915 MHzchannel spacing: 2 MHz
IEEE P802.15.4d/D2channel spacing:• 0.4 MHz GFSK• 0.6 MHz BPSK
November 2008
M. Schmidt and F. Poegel, AtmelSlide 5
doc.: IEEE 15-08-0797-00-004d
Submission
RX-Filter Attenuation(3-rd order Butterworth)
November 2008
M. Schmidt and F. Poegel, AtmelSlide 6
doc.: IEEE 15-08-0797-00-004d
Submission
Ωc [MHz]
(cut-off)
dΩAAC/ Ωc BW-3rd-order
attenuation
O-QPSK-250-kbit/s @915MHz 0.6 6.5 49
BPSK-40-kbit/s @915 MHz 0.6 6.5 49
GFSK-100-kbit/s @950 MHz 0.2 4 36
BPSK-20-kbit/s @950 MHz 0.3 4 36
RX-Filter Attenuation(3r-order Butterworth)
November 2008
M. Schmidt and F. Poegel, AtmelSlide 7
doc.: IEEE 15-08-0797-00-004d
Submission
• Based on a 3-rd order Butterworth filter, the relative attenuation loss is approx 13 dB
• Counteract by:– Decrease the cut-off frequency:
• Prone to filter tuning• Hard to implement for low-IF receiver architectures
– Increased filter order:• Additional die size• Increased power consumption
– Relax minimum receiver jamming resistance by approx 10 …15 dB
RX-Filter Attenuation(3rd-order Butterworth)
November 2008
M. Schmidt and F. Poegel, AtmelSlide 8
doc.: IEEE 15-08-0797-00-004d
Submission
Attenuation will further degrade due to:
• Frequency offset• Tolerances regarding filter tuning
Allow sufficient design margin!
RX-Filter Attenuation(3rd-order Butterworth)
November 2008
M. Schmidt and F. Poegel, AtmelSlide 9
doc.: IEEE 15-08-0797-00-004d
Submission
Suggested Requirements
• BPSK-20-kbit/s @ 950 MHz– Lower SNR required compared
to GFSK-PHY.
Adjacent channel
rejection
Alternate channel
rejection
0 dB 20 dB
• GFSK-100-kbit/s @ 950MHz– Higher SNR required
compared to BPSK-PHY.– It is desirable to use a
common receive filter for both PHYs, BPSK and GFSK.
Adjacent channel
rejection
Alternate channel
rejection
0 dB 10..15 dB