1. Submission Title: [A new ranging packet structure]
Project: IEEE P Working Group for Wireless Personal Area Networks (WPANs)
Submission Title: [A new ranging packet structure]
Date Submitted: September, 2005]
Source: [Yihong Qi, Huan-Bang Li, Shinsuke Hara and Ryuji Kohno, Company: National Institute of Information and Communications Technology ]
Contact: Yihong Qi
Voice: ,
Abstract: [A new ranging packet structure with a variable channel sounding length is devised. Its advantages include flexibility to accommodate a variety of ranging applications and limited complexity.]
Purpose: [To propose a new ranging packet structure]
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
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2. A new ranging packet structure
Yihong Qi, Huan-Bang Li, Shinsuke Hara and Ryuji Kohno National Institute of Information and Communications Technology (NICT)
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3. Current ranging packet
Preamble
Header
Payload
Data on timing, crystal offset, etc
Acquisition; channel sounding
Control information
contents
modulation
length
preamble
Acquisition; channel sounding
Ternary code
three lengths: 50us, 500us, 4ms
header
Control information
TBD
payload
Data on timing, crystal offset, etc
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4. What is the problem?
A variety of conflicting factors imposed by various (potential) ranging applications,
Mobility
Update rate
On-air time
Ranging accuracy
VS.
Current solution (?):
three preamble lengths, 50us, 500us and 4ms.
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5. Motivation to our approach
Use a ``flexible” data length for channel sounding/ranging
Avoid elaborating on specifics for mobility, update rate…
Let applications define their channel sounding lengths for ranging.
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6. A new ranging packet ( type I)
Multiplexing two (quasi-)orthogonal codes S1 and S2
Other modulation for data on timing, crystal offset, etc
Ternary code S1
Ternary code S1
Preamble
Header
Payload
header information modulated by S2
Point 2: Continue ranging/channel sounding by using S1
Point 1: Same preamble length as a communication packet or some basic lengths
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7. A new ranging packet (type II)
Only difference: Multiplexing two (quasi-)orthogonal codes S1 and S3 modulating real payload
Multiplexing two (quasi-)orthogonal codes S1 and S2
Ternary code S1
Preamble
Header
Payload
header information modulated by S2
Point 1: Same preamble length as a communication packet or some basic lengths
Point 2: Continue ranging/channel sounding by using S1
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8. New ranging packets in summary
contents
modulation
length
preamble
Acquisition/channel sounding
Ternary code S1
Same as a communication packet or some basic lengths
header
Control information/ channel sounding
Multiplexing two (quasi-)orthogonal S1 and S2
TBD
payload
Channel sounding/ data on timing, crystal offset, etc
Multiplexing two (quasi-)orthogonal S1 and S3
variable
Note: S2 and S3 are selected from a different code set with S1
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9. Features Preamble length longer than that of a communication packet
Guarantee header information to be demodulated (understood) correctly
Flexible data length for channel sounding
Accommodate various factors such as ranging accuracy, mobile speed, update rate.
Multiplexing two (quasi-)orthogonal codes S1 and S2 in the header for a ``non-interruptive” channel sounding
S2 is used to modulate header information
S1 is for channel sounding
Multiplexing two (quasi-)orthogonal codes S1 and S3 in the payload
A compact ranging packet
Useful for applications involving mobility and frequent updates
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10. Advantages
Flexible to a variety of requirements on ranging accuracy and applications
Avoiding specifications on update rate, ranging distance and mobility
Possible to adjust the channel sounding length in a real-time manner
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11. Complexity and Non-coherent issues
Work with non-coherent receivers
Performance degraded as in a SOP scenario but in a controllable manner
Need multiple code correlators corresponding to codes S1, S2 and S3
Same as the requirement of a regular ranging packet
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12. Conclusions A new ranging packet structure
Flexible to accommodate various potential applications
With limited impact on non-coherent performance and complexity
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