doc.: ieee 802.11-07-0111-00-000v submission january 2007 ivan reede reede slide 1 ranging and...

January 2007

Ivan Reede Reede

Slide 1

doc.: IEEE 802.11-07-0111-00-000v

Submission

Ranging and Location for 802.11 LANsIEEE P802.22 Wireless RANs Date: 2007-01-15

Name Company Address Phone email

Authors:

Notice: This document has been prepared to assist IEEE 802.11. 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 grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802.11.

Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures http://standards.ieee.org/guides/bylaws/sb-bylaws.pdf including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard." Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair [email protected] as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802.11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at [email protected].

Ivan Reede Montreal,CA 514-620-86522 [email protected]

January 2007

Ivan Reede Reede

Slide 2

doc.: IEEE 802.11-07-0111-00-000v

Submission

Abstract

This document was first presented to the IEEE802.22 group in July, Oct, Nov06 and Jan07.

Currently, it is adapted to 802.22 needs

The means presented here and the simulation results can be adapted to the geolocation needs of the IEEE802.11 TGV

With minimal if any hardware modifications

The presentation and simulation results needs scaling to be made to some parameters like:- Carrier spacing, number of carriers, symbol duration, etc.

Operating principles remain

January 2007

Ivan Reede Reede

Slide 3

doc.: IEEE 802.11-07-0111-00-000v

Submission

Abstract

A means to range802.11 links from AP to Stations

inter station distances

inter AP distances

Means to apply obtained results to establish the geographic location of these devices

January 2007

Ivan Reede Reede

Slide 4

doc.: IEEE 802.11-07-0111-00-000v

Submission

Abstract

Simulation results Perfect channel

802.22 Channel A

802.22 Channel B

802.22 Channel C

802.22 Channel D

January 2007

Ivan Reede Reede

Slide 5

doc.: IEEE 802.11-07-0111-00-000v

Submission

• OFDM receivers inherently effect range bearing information collection in normal operations

• Such information is required for their operation• Such information has not yet been recognized in any public

documentation as range bearing• In a 6 MHz BW channel, 1 meter ranging resolution may be

achieved

By the following means...

OFDM System ExampleAssertion Overview

January 2007

Ivan Reede Reede

Slide 6

doc.: IEEE 802.11-07-0111-00-000v

Submission

OFDM System ExampleFounding Premises

• OFDM systems transmit using a plurality of carriers• These carriers are at slightly different frequencies at RF, but

are harmonically related at baseband• They are related by the fact that they are all transmitted

simultaneously in a package called an OFDM symbol

January 2007

Ivan Reede Reede

Slide 7

doc.: IEEE 802.11-07-0111-00-000v

Submission

• The source of the OFDM symbol is usually an IFFT device• The symbol output is generally composed of a sum of sine

and cosine waves• All of these sine and cosine waves

– Start at the beginning of each symbol– End at the end of each symbol– Sine waves begin and end with zero values– Cosine waves begin and end with full amplitude values at symbol edges

OFDM System ExampleModel Overview

January 2007

Ivan Reede Reede

Slide 8

doc.: IEEE 802.11-07-0111-00-000v

Submission

• The receiver is generally composed of an FFT device• This device acts as a multi-carrier QPSK or n-QAM

demodulator• Each carrier can be demodulated as QPSK, 16-QAM,

64-QAM or other• As such, the OFDM receiver extracts amplitude and

phase information from each carrier


January 2007

Ivan Reede Reede

Slide 9

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Current receiver designs use pilot carriers to align the constellation demodulation process

• Assume, by standardization– That a pilot carrier be emitted with a known phase

• The receiver, in aligning to this carrier, essentially effects a “phase lock” to this pilot

• It demodulates with a known phase resolution– ~±45° for QPSK, ~±7.5° for 64-QAM


January 2007

Ivan Reede Reede

Slide 10

doc.: IEEE 802.11-07-0111-00-000v

Submission

To demodulate QPSKphase lock must be

much better than ±45°

OFDM System ExampleQPSK Constellation

January 2007

Ivan Reede Reede

Slide 11

doc.: IEEE 802.11-07-0111-00-000v

Submission

To demodulate 16-QAMphase lock must be

much better than ±19°

OFDM System Example16-QAM Constellation

January 2007

Ivan Reede Reede

Slide 12

doc.: IEEE 802.11-07-0111-00-000v

Submission

To demodulate 64-QAMphase lock must be

much better than ±7.5°

OFDM System Example64-QAM Constellation

January 2007

Ivan Reede Reede

Slide 13

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Transmitters internally use a precise clock to emit the IFFT symbol samples

• The symbols they transmit are related to this clock• By transmitting an OFDM symbol, they inherently

broadcast their space-time reference frame, relative to their geolocation and their clock

OFDM System ExampleTransmitter Space-Time Reference Frame

January 2007

Ivan Reede Reede

Slide 14

doc.: IEEE 802.11-07-0111-00-000v

Submission

Tx

Symbols emanatingfrom the transmitter

Transmitted wave conveys the Tx's Space-time frame

OFDM System ExampleTransmitter Space-Time Reference Frame

January 2007

Ivan Reede Reede

Slide 15

doc.: IEEE 802.11-07-0111-00-000v

Submission

• If the receiver knew exactly at what time the symbol was sent by the transmitter, the receiver could determine the distance from the flight time

• The receiver lacks this knowledge• The receiver, however, has an internal clock used

to acquire and store samples of the received wave• With this clock, the receiver can create a rough

relative space-time frame from a received OFDM symbol

OFDM System ExampleReceiver Premises

January 2007

Ivan Reede Reede

Slide 16

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Assume a transmitter emits an OFDM symbol that contains a pilot carrier whose frequency is 3 Khz

• The period of this wave is 333,333,333 ns– This is much longer than the ¼ symbol guard time

• The wavelength of this wave is ~100 km• A 64-QAM receiver, resolves this pilot within ±7.5°• This creates a receiver relative space-time frame

– to a 2.08 km resolution (100km * 7.5°/360°)– The phase of the demodulated signal depends on sampling

aperture slip in the guard interval

OFDM System ExampleFundamental Operating Principles

January 2007

Ivan Reede Reede

Slide 17

doc.: IEEE 802.11-07-0111-00-000v

Submission

1

1

vp

10 p

sam ples

0 0 . 063 0 . 13 0 . 19 0 . 25 0 . 31 0 . 38 0 . 44 0 . 5 0 . 56 0 . 63 0 . 69 0 . 75 0 . 81 0 . 88 0 . 94 11

0

1B a s e b a n d t im e d o m a in s ig n a l

D A C ou tp u t sam p le #

OFDM System ExampleTransmitted 3 Khz Wave Symbol

January 2007

Ivan Reede Reede

Slide 18

doc.: IEEE 802.11-07-0111-00-000v

Submission

A ±7.5° quantizationamounts to ±2.08 km

space-time uncertainty

OFDM System ExampleReceiver Space-Time Reference Frame

January 2007

Ivan Reede Reede

Slide 19

doc.: IEEE 802.11-07-0111-00-000v

Submission

A ±7.5° quantizationamounts to a

100 km range ±2.08 kmspace-time frame

uncertainty

Rx

Tx

OFDM System ExampleReceiver 3 Khz wave Space-Time Reference Frame

January 2007

Ivan Reede Reede

Slide 20

doc.: IEEE 802.11-07-0111-00-000v

Submission

A ±7.5° quantizationamounts to a

100 km range ±2.08 kmspace-time frame

uncertainty

Rx

Tx

Receiver 3KHz wave Space-time frame

OFDM System ExampleReceiver 3 Khz wave Space-Time Reference Frame Snapshot

January 2007

Ivan Reede Reede

Slide 21

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Assume the transmitter emits an OFDM symbol that contains a pilot carrier whose frequency is 6 KHz

• The period of this wave is 166,666,667 ns– This is much longer than the ¼ symbol guard time


– to a 1.04 km resolution (50km * 7.5°/360°)– The phase of the demodulated signal depends on sampling aperture

slip in the guard interval

OFDM System Example(cont.)

January 2007

Ivan Reede Reede

Slide 22

doc.: IEEE 802.11-07-0111-00-000v

Submission

Transmitted 6 KHz wave symbol

1

1

vp

10 p

sam ples

0 0 . 063 0 . 13 0 . 19 0 . 25 0 . 31 0 . 38 0 . 44 0 . 5 0 . 56 0 . 63 0 . 69 0 . 75 0 . 81 0 . 88 0 . 94 11

0




January 2007

Ivan Reede Reede

Slide 23

doc.: IEEE 802.11-07-0111-00-000v

Submission

Rx

Tx

Receiver 3 and 6 Khz wave Space-time frame


January 2007

Ivan Reede Reede

Slide 24

doc.: IEEE 802.11-07-0111-00-000v

Submission

A ±7.5° quantizationover 360° amounts to ±1.04 km resolutionover a 50 km range space-time frame

uncertainty

Rx

Tx

Receiver 6 Khz wave Space-time frame

The space-time framewraps twice through 360°

in a symbol


January 2007

Ivan Reede Reede

Slide 25

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Using both pilots, the OFDM 64-QAM receiver• May create a space-time frame

– With 1.04 km resolution


January 2007

Ivan Reede Reede

Slide 26

doc.: IEEE 802.11-07-0111-00-000v

Submission

Transmitted 3 and 6 KHz waves symbol

1 .755

1 .755

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

0


D A C ou tpu t sam p le #

OFDM System ExampleTransmitted 3 and 6 Khz Wave Symbol

January 2007

Ivan Reede Reede

Slide 27

doc.: IEEE 802.11-07-0111-00-000v

Submission

Rx

Tx

Receiver 3 and 6 Khz wave Space-time frame

Using both wavesyields an unwrapped

2 km resolution100 km range

space-time frame


January 2007

Ivan Reede Reede

Slide 28

doc.: IEEE 802.11-07-0111-00-000v

Submission


• The period of this wave is 83,333,333 ns– This is only slightly longer than the ¼ symbol guard time– A 64-QAM receiver, resolves this pilot within ±7.5°


– With 0.52 km resolution (25km * 7.5°/360°)– The phase of the demodulated signal depends on sampling



January 2007

Ivan Reede Reede

Slide 29

doc.: IEEE 802.11-07-0111-00-000v

Submission

Transmitted 12 KHz wave symbol

1

1

vp

10 p

sam ples

0 0 . 063 0 . 13 0 . 19 0 . 25 0 . 31 0 . 38 0 . 44 0 . 5 0 . 56 0 . 63 0 . 69 0 . 75 0 . 81 0 . 88 0 . 94 11

0




January 2007

Ivan Reede Reede

Slide 30

doc.: IEEE 802.11-07-0111-00-000v

Submission

Transmitted 3 and 6 and 12 KHz wave symbol

2 .227

2 .227

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 14

2

0

2



OFDM System ExampleTransmitted 3 and 6 and 12 Khz Wave Symbol

January 2007

Ivan Reede Reede

Slide 31

doc.: IEEE 802.11-07-0111-00-000v

Submission

Rx

Tx

Receiver 3 and 6 and 12 Khz wave Space-time frame

Using all 3 wavesyields an unwrapped0.52 km resolution

100 km rangespace-time frame


January 2007

Ivan Reede Reede

Slide 32

doc.: IEEE 802.11-07-0111-00-000v

Submission


• The period of this wave is 41,666,667 ns– This is only slightly longer than the ¼ symbol guard time– A 64-QAM receiver, resolves this pilot within ±7.5°

• The wavelength of this wave is ~12.5 km• A 64-QAM receiver, resolves this pilot within ±7.5°• This creates a receiver relative space-time frame

– With 0.251 km resolution (12.5km * 7.5°/360°)– The phase of the demodulated signal depends on sampling



January 2007

Ivan Reede Reede

Slide 33

doc.: IEEE 802.11-07-0111-00-000v

Submission


• The period of this wave is 20,833,333 ns– This is shorter than the ¼ symbol guard time– A 64-QAM receiver, resolves this pilot within ±7.5°

• The wavelength of this wave is ~12.5 km• A 64-QAM receiver, resolves this pilot within ±7.5°• This creates a receiver relative space-time frame

– With 0.251 km resolution (12.5km * 7.5°/360°)– The phase of the demodulated signal depends on sampling



January 2007

Ivan Reede Reede

Slide 34

doc.: IEEE 802.11-07-0111-00-000v

Submission

• This wave's phase wraps beyond 360° within the guard period

• This wave alone therefore can't resolve to relative space-time frame, as there may be up to 2 space-time frames that satisfy the detected phase

• The assistance of a longer wave is required to counteract the inability of the demodulator to see beyond a 360° horizon

• Using this wave and at least one of the longer waves, the demodulator's limitations can be overcome


January 2007

Ivan Reede Reede

Slide 35

doc.: IEEE 802.11-07-0111-00-000v

Submission

• With more pilot's, as follows

3000 100000 2083.33 5277.78 125006000 50000 1041.67 2638.89 6250

12000 25000 520.83 1319.44 312524000 12500 260.42 659.72 1562.548000 6250 130.21 329.86 781.2596000 3125 65.1 164.93 390.63192000 1562.5 32.55 82.47 195.31384000 781.25 16.28 41.23 97.66768000 390.63 8.14 20.62 48.83

1536000 195.31 4.07 10.31 24.413072000 97.66 2.03 5.15 12.215997000 50.03 1.04 2.64 6.25

Pilot Baseband Frequency (Hz)

Wavelength range (m)

'±7.5° rangeresolution (m)

'±19° rangeresolution (m)

'±45° rangeresolution (m)


January 2007

Ivan Reede Reede

Slide 36

doc.: IEEE 802.11-07-0111-00-000v

Submission

Example Transmitted 12 pilot wave symbol

6 .411

6 .411

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 110

5

0

5



OFDM System ExampleTransmitted 12 Pilot Example Wave Symbol

January 2007

Ivan Reede Reede

Slide 37

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Using multiple pilots, the OFDM 64-QAM receiver• May create a space-time frame

– With 1 m resolution

• It still does not know the transmitter to receiver distance

• It knows a space-time frame of the signal– In terms I-Q information about a set of pilot tones

• It can return this information to the transmitter


January 2007

Ivan Reede Reede

Slide 38

doc.: IEEE 802.11-07-0111-00-000v

Submission

• The receiving station can respond to queries, in a manner synchronous to the center of this space-time frame.

• The initial transmitter, when it receives a response from the station, can also establish a similar space time frame

• The discrepancy between the transmitter's initial space-time frame and the responses space-time frame reveals the total flight time

• Taking into account that the receiver is able to receive 12 dB SNR signals, the phase lock of real receivers must be much better and the total travel time can be estimated to within ~±0.5m resolution


January 2007

Ivan Reede Reede

Slide 39

doc.: IEEE 802.11-07-0111-00-000v

Submission


• The AP sends a ranging query• Flight time later, station receives the query• Using the transmitted OFDM symbol and the method

described herein, station stores the 64-QAM detector output set and prepares a response containing this set

AP Station

January 2007

Ivan Reede Reede

Slide 40

doc.: IEEE 802.11-07-0111-00-000v

Submission


• At a precise moment later, after a known delay• Delay

– Defined in the standard– Or specified by the BS scheduling

• Station responds to the AP• By emitting an OFDM symbol containing

– The pilots required to satisfy the means described herein– The prepared response

AP Station

January 2007

Ivan Reede Reede

Slide 41

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Flight time later• AP receives station response• Using the transmitted OFDM symbol and the method

described herein, AP stores the 64-QAM detector output set• BS sends both the acquired response and its received set

– Station 64-QAM output set– AP 64-QAM output set– AP recorded query-response delay time stamp (sampling clock based)

• To the geolocator resolver for processing

AP Station

January 2007

Ivan Reede Reede

Slide 42

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Other stations, hearing query responses, may also perceive and measure space-time frame discrepancies.

• These discrepancies reveal flight times, within ~±0.5 m resolution

• A collectivity of stations can accumulate a wealth of space-time frame discrepancies

• Once collected and processed, this information reveals precise station location and channel characteristics


January 2007

Ivan Reede Reede

Slide 43

doc.: IEEE 802.11-07-0111-00-000v

Submission

OFDM Ranging SummaryCosts

• Requires minimal abilities in stations• Requires at least three located waypoints, at the AP or station

or some other known location characteristics• Economical

– it better exploits existing OFDM hardware– many pilot tones are already there for constellation sync– ranging symbols may be data bearing– practically no overhead– no external costs (such as GPS system costs + installation)

• Does not require many added abilities out of the station

January 2007

Ivan Reede Reede

Slide 44

doc.: IEEE 802.11-07-0111-00-000v

Submission

OFDM Ranging SummaryBenefits

• Simple, pilot tones are already there for constellation sync• Fast and precise results, from a single query-response

– Provides the required resolution– Provides enough resolution for 3d location, including feed lines– Provides support for fixed devices– Provides support for mobility detection and tracking

• Is amenable to processing gain means on range and precision• Is self supportive, does not require external technology assists• Provides the ranging information needed to geolocate devices in

a simple, economical, elegant, inband and transparent fashion

January 2007

Ivan Reede Reede

Slide 45

doc.: IEEE 802.11-07-0111-00-000v

Submission

Alternatives?

• Is there another way to achieve the same goals?• Can we adapt this to allow OFDMA support?

January 2007

Ivan Reede Reede

Slide 46

doc.: IEEE 802.11-07-0111-00-000v

Submission

Alternatives?

• Is there another way to achieve the same goals?• Can we adapt this to allow OFDMA support?

The answer is YES ... to both questions

January 2007

Ivan Reede Reede

Slide 47

doc.: IEEE 802.11-07-0111-00-000v

Submission

Guard and Cyclic Prefix Needs

• In order to avoid filtering problems and multipath effects– A prefix is usually added to the transmitted signal– This provides time for filters to stabilize and stop “ringing”

• At the beginning of each symbol– Allows the receiving PHY to have some slack in its sync

• This slack has the apparent negative effect– Of negating the timing precision of the system

• This can be compensated after the FFT process

January 2007

Ivan Reede Reede

Slide 48

doc.: IEEE 802.11-07-0111-00-000v

Submission


v t( )

0

N 1

k

I k ei

2 k t

T

=

ii

0 t T

v t( )

0

N 1

k

I k ei

2 k t

T

=

ii

Tg

t T

January 2007

Ivan Reede Reede

Slide 49

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



Starting discontinuity Tail end always aligns with the starting discontinuity

January 2007

Ivan Reede Reede

Slide 50

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



Starting discontinuity has been masked by copyingtail end and inserting itas a cyclic prefix

January 2007

Ivan Reede Reede

Slide 51

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



Initial filter ringing and inter-symbol interference has the time to decay before acquisition begins

January 2007

Ivan Reede Reede

Slide 52

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1


D A C ou tpu t sam p le #Signal acquisition interval does not have to be precisely aligned to get a valid orthogonal signal set

January 2007

Ivan Reede Reede

Slide 53

doc.: IEEE 802.11-07-0111-00-000v

Submission

Handling Guard and Cyclic Prefix

• Any time domain offset is mapped in the frequency domain• By a phase offset set in the recovered pilot carriers

– Phase offset values are proportional to pilot carrier frequency• The MAC may then compute the corresponding time offset

– Feed it back to the PHY for direct time stamp correction– Transmit correction data to the AP and other stations

• The AP receiving correction may compensate time offsets• Relaying stations have the option of

– Compensating– Relaying a compounded value back to the AP

January 2007

Ivan Reede Reede

Slide 54

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



In the following examplewe will assume acquisitionstarted 12.5uSec before thereal symbol start

January 2007

Ivan Reede Reede

Slide 55

doc.: IEEE 802.11-07-0111-00-000v

Submission

Computing the PHY “slop”

• The PHY in its reception process– Acquires samples of the incoming signal– May establish a “sloppy” sync to symbol boundaries– Pass this “sloppy symbol” to the FFT– Which takes the acquired samples and decodes them– Into an array of vectors in an array of constellations

January 2007

Ivan Reede Reede

Slide 56

doc.: IEEE 802.11-07-0111-00-000v

Submission


Rotation is mappedto acquisition delay

3 KHz pilot tone

-15° ± 7.5°± 6.25 uSec± 2km

• The MAC can then acquire a first-order fix– By examination of the lowest frequency carrier– Normalize the array of vectors to this lowest frequency vector– This normalization yields a first order “slop” correction term

• The MAC can then predict the next tone angle

January 2007

Ivan Reede Reede

Slide 57

doc.: IEEE 802.11-07-0111-00-000v

Submission


Higher frequency pilot carrier is rotated more thanlower frequencypilot carrier

6 KHz pilot tone

• The MAC can then– Refine its error estimate by examining the next carrier– This normalization yields a higher order correction term

• Prediction in this example was 30° ± 15° (± 2 km)– This step reduces the ± 2 km down to ± 1 km

• The MAC can then predict the next tone angle

-30° ± 7.5°± 3.125uSec± 1 km

January 2007

Ivan Reede Reede

Slide 58

doc.: IEEE 802.11-07-0111-00-000v

Submission


12 KHz pilot tone

• Repeat the process with ever increasing frequency carriers– Until the desired range resolution is obtained

-60° ± 7.5°± 1.56 uSec± 500 m

January 2007

Ivan Reede Reede

Slide 59

doc.: IEEE 802.11-07-0111-00-000v

Submission


24 KHz pilot tone

• Repeat the process with ever increasing frequency carriers– Until the desired range resolution is obtained

-120° ± 7.5°± 0.78 uSec± 250 m

January 2007

Ivan Reede Reede

Slide 60

doc.: IEEE 802.11-07-0111-00-000v

Submission


192 KHz pilot tone

384 KHz pilot tone

-240° ± 7.5°± 0.39 uSec± 125 m

-480° ± 7.5°± 0.20 uSec± 62.5 m

January 2007

Ivan Reede Reede

Slide 61

doc.: IEEE 802.11-07-0111-00-000v

Submission


768 KHz pilot tone

1536 KHz pilot tone

-960° ± 7.5°± 0.10 uSec± 31.25 m

-1920° ± 7.5°± 0.05 uSec± 15.6 m

January 2007

Ivan Reede Reede

Slide 62

doc.: IEEE 802.11-07-0111-00-000v

Submission


768 KHz pilot tone

1536 KHz pilot tone

-3840° ± 7.5°± 0.025 uSec± 8 m

-7860° ± 7.5°± 0.0125 uSec± 4 m

January 2007

Ivan Reede Reede

Slide 63

doc.: IEEE 802.11-07-0111-00-000v

Submission


3072 KHz pilot tone

5997 KHz pilot tone

-15360° ± 7.5°± 0.0063 uSec± 2 m

-29985° ± 7.5°± 0.003 uSec± 1 m

January 2007

Ivan Reede Reede

Slide 64

doc.: IEEE 802.11-07-0111-00-000v

Submission

Compensating the PHY “slop”

• Once the desired resolution is reached• Store the acquired 64-QAM output set• Upon request from the AP, the station can transmit

– The acquired 64-QAM output set– A set of pilot tones, as specified by the AP

January 2007

Ivan Reede Reede

Slide 65

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



MAC knows that PHY acquisition frame is off set by 12.500 ±0.003 uSec

January 2007

Ivan Reede Reede

Slide 66

doc.: IEEE 802.11-07-0111-00-000v

Submission

Accommodating Guard

• This process allows for both– Real-life OFDM Receiver PHY sync limitations– OFDMA operation

• Where many stations – Share carrier resources in a given channel– Transmit in such a way to have all station space-time

frames• Arrive simultaneously at the AP• With space-time frame timing offset data

• This process allows the AP confirm its range estimates– By requesting a station additional pilots in OFDMA mode

January 2007

Ivan Reede Reede

Slide 67

doc.: IEEE 802.11-07-0111-00-000v

Submission

Pilot Tone Selection

• It is very important to understand– The the choice of a dozen pilots in these examples

• Is arbitrary, for example purposes only• Can dynamically be reduced or increased to

– Accommodate channel characteristics– Provide more statistical data– Allow for processing gain and artifact reduction

• In good 64-QAM, line of sight channels, 4 pilots are sufficient• In bad channels, many more pilots may be desired

– To compensate noise– To counteract and discard deviant pilot readings

January 2007

Ivan Reede Reede

Slide 68

doc.: IEEE 802.11-07-0111-00-000v

Submission

Resolution is NOT Precision

• It is very important to understand– That although this system has 2m resolution capability– In practice, absolute precision is always lower than resolution

• Channel artifacts limit precision in radio-location systems– Mutipath (reflections, scatter, refraction-index variance)– Doppler, fading, weather-related media properties, etc...– They apply in various degrees to ALL radio-location systems– ALL radio-location systems are subject to similar limitations

• The goal is to meet 802.11 network geolocation precision needs– TBD m– TBD km positional stability (station motion-cutoff threshold)

January 2007

Ivan Reede Reede

Slide 69

doc.: IEEE 802.11-07-0111-00-000v

Submission

Providing for OFDMA Flexibility

• It is proposed that a MAC to MAC primitive be created• To allow a AP or station MAC to inform any receiving MACs• About the 64-QAM output set

January 2007

Ivan Reede Reede

Slide 70

doc.: IEEE 802.11-07-0111-00-000v

Submission

Providing OFDMA Hooks

• It is proposed that a MAC protocol primitive– Allows for inclusion or suppression from a station's spectrum

• Of ranging pilots• To allow for OFDMA operation

– Without superposition of standard ranging pilots• From a universe of stations

• To allow the AP to specify alternate station to AP ranging carriers

• To allow coherent, simultaneous ranging of many stations• Validate and verify range estimates• Allow for selective fading in the channel

January 2007

Ivan Reede Reede

Slide 71

doc.: IEEE 802.11-07-0111-00-000v

Submission

MAC Assisted Ranging SummaryBenefits

• Fast and precise results, from a single query-response– Provides the required resolution without high-speed clocks– Provides for OFDMA operation with real-life add-ons

• Is amenable to processing gain– Statistical processing can, over multiple samples

• Quantify, via analysis– Noise and multi-path properties

• Reduce, by algorithms performing averaging processes– Noise (i.e. Effectively reducing BW)– Analyze unstable multi-path artifacts (wobble, Doppler...)

– Perform and correct for station clock drift and offset

January 2007

Ivan Reede Reede

Slide 72

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Opens an opportunity to understand and and differentiate– Artifacts that are station specific– Artifacts that affect many stations in a region– Artifacts that affect all stations connected to a AP

• Analyze and understand how these artifacts affect the channel• Reduce, by future algorithmic analysis

– Errors caused by these artifacts– Take corrective action

This may only be possible for in-band radio-location means

January 2007

Ivan Reede Reede

Slide 73

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Simple, the pilot tones are already there for constellation sync– Pilot tone set should be flexible

• Accommodates fading and multipath• Avoids worst-case fading pilot carrier frequencies• Allows the AP to explore the channel characteristics

• Is self supportive, does not require external technology assists– Hardware time stamp is already needed for OFDMA– Extreme temporal precision is achieved by processing gain

• Provides the ranging information needed to geolocate devices in a simple, economical, elegant, inband and transparent fashion

January 2007

Ivan Reede Reede

Slide 74

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results

• Methodology used• Assumptions and results

January 2007

Ivan Reede Reede

Slide 75

doc.: IEEE 802.11-07-0111-00-000v

Submission

AP to Station MAC Command Elements

• AP address• Station address• Listen_From source address• Send_To destination address• Response_Delay

– In sampling clock cycles (~146ns/cycle)

• Reply Tone_Set carriers

January 2007

Ivan Reede Reede

Slide 76

doc.: IEEE 802.11-07-0111-00-000v

Submission

Station to AP MAC Reply Elements

• AP address• Station address• Listen_From source address• Send_To destination address• Station 64-QAM set• Reply Tone_Set

– as specified by the AP to the station

January 2007

Ivan Reede Reede

Slide 77

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Geolocator asks AP to get AP-station1 ranging data– Using two specific tone sets

• Query Tone_Set (for AP to station1 ranging)• Response Tone_Set (for station1 to AP ranging)

– These two tone sets may be identical

AP Station1

Ranging Example(AP to station1 to AP)

GeoLocator

January 2007

Ivan Reede Reede

Slide 78

doc.: IEEE 802.11-07-0111-00-000v

Submission

• AP emits a MAC command asking Station1– To acquire upcoming 64-QAM set

• From AP MAC address as Listen_From• Using AP MAC address as Send_To• With Query Tone_Set description

– To respond after a specific Response_Delay– And to emit reverse ranging Response Tone_Set

• AP then emits– AP to station ranging tone set– Starts it's alignment-counter, operating at sampler frequency

AP Station1

Ranging Example(AP to Station1 to AP)

MAC commandQuery Tone_Set

January 2007

Ivan Reede Reede

Slide 79

doc.: IEEE 802.11-07-0111-00-000v

Submission

Ranging Example(AP to Station1 to AP cont.)

• Station1– At the moment it starts acquiring Tone_Set incoming sample– Starts or aligns it's scheduling-counter, operating at sampler frequency– There on, the scheduling-counter is counting time from

• The exact beginning of the sample acquisition window• Beginning which occurred somewhere within the guard period• In sampling clock increments (146ns)

AP Station1Query Tone_Set

January 2007

Ivan Reede Reede

Slide 80

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Station1 receiver– Does not know a priori and does not care about

• Where in the guard interval • It started acquiring incoming sample

• However– Station1's scheduling_counter

• Is aligned with the moment it's receiver• Started the acquisition• Will be used to count down the Response_Delay• And to control the starting moment of the response Tone_Set emission

AP Station1

January 2007

Ivan Reede Reede

Slide 81

doc.: IEEE 802.11-07-0111-00-000v

Submission


2

1 .125

vp

10 p

sam ples

0 0 .063 0 .13 0 .19 0 .25 0 .31 0 .38 0 .44 0 .5 0 .56 0 .63 0 .69 0 .75 0 .81 0 .88 0 .94 12

1

0

1



In the simulation, this is the “Err” valueand “graph(Err,n)” is the difference between the computed alignment error and the actual Err value

scheduling_counter is aligned to this moment in time

ISI decay delay

acquisition window

January 2007

Ivan Reede Reede

Slide 82

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Station1– Demodulates incoming sample– Extracts Station1_64-QAM_set

• For specified query Tone_Set• Without any phase or amplitude corrections• That could be applied by the channel estimator

– Stores the result and prepares a response

AP Station1

January 2007

Ivan Reede Reede

Slide 83

doc.: IEEE 802.11-07-0111-00-000v

Submission


• After scheduled delay– Station1 responds with

• MAC response– Station1 MAC source address– AP dest address (aka Send_To)– Station1 64-QAM set

• Response Tone_Set

AP Station1MAC response Response Tone_Set

January 2007

Ivan Reede Reede

Slide 84

doc.: IEEE 802.11-07-0111-00-000v

Submission


• AP, after scheduled delay – listens for response from Listen_From

• This means AP may start waiting for the response– Before Station1 actually starts responding

• AP may wait, before the response is acquired– AP to Station1 flight time– Minus Station1 acquisition window alignment error– Plus Station1 to AP flight time– Minus AP acquisition window alignment error

AP Station1MAC response Response Tone_Set

January 2007

Ivan Reede Reede

Slide 85

doc.: IEEE 802.11-07-0111-00-000v

Submission


• AP, after scheduled delay – At the moment it starts acquiring Tone_Set incoming samples– Stops it's alignment-counter, operating at sampler frequency (146 ns)– There on, the alignment-counter indicates time from

• The starting moment the query Tone_Set emission• To the starting moment of the response Tone_Set sample acquisition window

– which occurred somewhere within the response guard period

AP Station1Response Tone_Set

January 2007

Ivan Reede Reede

Slide 86

doc.: IEEE 802.11-07-0111-00-000v

Submission


• AP– Offsets the alignment_counter by deducting the Response_Delay

• alignment_counter now contains a value representing– AP to Station1 flight time– Minus Station1 acquisition window alignment error– Plus Station1 to AP flight time– Minus AP acquisition window alignment error– Within sampling clock resolution– Independent of AP/Station transmission scheduling artifacts

AP Station1Response Tone_Set

January 2007

Ivan Reede Reede

Slide 87

doc.: IEEE 802.11-07-0111-00-000v

Submission


• AP– Demodulates incoming sample– Extracts AP_64-QAM_set

• For specified response Tone_Set• Without any phase or amplitude corrections• That could be applied by the channel estimator

– Stores the result

AP Station1

January 2007

Ivan Reede Reede

Slide 88

doc.: IEEE 802.11-07-0111-00-000v

Submission


• AP, returns to the geolocator, the following– alignment_counter value– Station1_64-QAM_set– AP_64-QAM_set

AP Station1

GeoLocator

January 2007

Ivan Reede Reede

Slide 89

doc.: IEEE 802.11-07-0111-00-000v

Submission


• Geolocator performs computations– From Station1_64-QAM_set, computes Station1 receiver alignment

error• This also precisely reveals response Tone_Set emission moment• As the start of the emission of the response Tone_Set • Was aligned to Station1's scheduling_counter• Itself aligned by Station1's receiver acquisition window starting moment

– From AP_64-QAM_set, computes AP receiver alignment error– Deducts both errors from alignment_counter

• With fine resolution (in the order of a nanosecond)

– Scales the result by the speed of light and the sampling frequency– Divides the result by 2, yielding the AP-Station1 range

January 2007

Ivan Reede Reede

Slide 90

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Geolocator ask AP to get a ranging query confirmation through Station2– Using a specific a tone set

• AP asks Station2– To acquire 64-QAM set– From Station1 MAC address as Listen_From– Specifying a scheduled response delay– Using AP MAC address as Send_To– Reply with Tone_Set

AP Station1

Ranging Example(AP to Station1 to Station2 to AP)

Station2

January 2007

Ivan Reede Reede

Slide 91

doc.: IEEE 802.11-07-0111-00-000v

Submission

• AP asks Station1– To acquire 64-QAM set– From AP MAC address as Listen_From– Specifying a scheduled response delay– Using Broadcast MAC address as Send_To– Reply with Tone_Set

• AP emits AP to Station1 ranging tone set

AP Station1


Station2

January 2007

Ivan Reede Reede

Slide 92

doc.: IEEE 802.11-07-0111-00-000v

Submission

AP Station1


Station2

• Station1 acquires Station1 64-QAM set• After scheduled delay

– Station1 responds with• Station1 MAC address, Broadcast dest address, Station1 64-QAM set• Station1 Tone_Set

– AP • listens for response from Listen_From• Acquires AP 64-QAM set and stores it along with Station1 64-QAM set• Sends the stored data to the geolocator for resolution

January 2007

Ivan Reede Reede

Slide 93

doc.: IEEE 802.11-07-0111-00-000v

Submission

AP Station1


Station2

• Station1 acquires Station1 64-QAM set• After scheduled delay

– Station2• listens for response from Station1• Acquires Station2 64-QAM set and stores it along with Station1 64-QAM set

January 2007

Ivan Reede Reede

Slide 94

doc.: IEEE 802.11-07-0111-00-000v

Submission

AP Station1


Station2

• Station2 acquires Station1 64-QAM set• After further scheduled delay

– Station1 responds to AP with• Station2 MAC address, AP dest address (aka Send_To), Station2 64-QAM set• Station2 Tone_Set

January 2007

Ivan Reede Reede

Slide 95

doc.: IEEE 802.11-07-0111-00-000v

Submission

Methodology usedRx Block Diagram

FFT+QAMDownconverter Sampler FFT

64-QAM Quantizer

Memory

I

Q

Re Im

January 2007

Ivan Reede Reede

Slide 96

doc.: IEEE 802.11-07-0111-00-000v

Submission

Methodology usedRx 64-QAM Quantizer

Q A M 6 4 x( ) .8 7 5( ) R e x( ) .7 5if

.6 2 5( ) .7 5 R e x( ) .5if

.3 7 5( ) .5 R e x( ) .2 5if

.1 2 5( ) .2 5 R e x( ) 0if

.1 2 5 0 R e x( ) .2 5if

.3 7 5 .2 5 R e x( ) .5if

.6 2 5 .5 R e x( ) .7 5if

.8 7 5 o t h e rw is e

.8 7 5 j( ) Im x( ) .7 5if

.6 2 5 j( ) .7 5 Im x( ) .5if

.3 7 5 j( ) .5 Im x( ) .2 5if

.1 2 5 j( ) .2 5 Im x( ) 0if

.1 2 5 j 0 Im x( ) .2 5if

.3 7 5 j .2 5 Im x( ) .5if

.6 2 5 j .5 Im x( ) .7 5if

.8 7 5 j o t h e rw is e

January 2007

Ivan Reede Reede

Slide 97

doc.: IEEE 802.11-07-0111-00-000v

Submission

Methodology used64-QAM Quantizer accepted points

1

1

Im Q A M 64 1 ( )

Im Q A M 64 2 ( )

11 R e Q A M 64 1 ( ) R e Q A M 64 2 ( )1 0 . 75 0 . 5 0 . 25 0 0 . 25 0 . 5 0 . 75 1

1

0 . 75

0 . 5

0 . 25

0

0 . 25

0 . 5

0 . 75

1

If a carrier lands outside the red or blue points, it is rejected.A substitute carrier may be used.

January 2007

Ivan Reede Reede

Slide 98

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Let– “offset” be the sampling window offset in cycles– “x” be the phase– “n” be the carrier number– “ResErr” is the total phase offset

Methodology usedGeolocator sampling aperture error resolver

R e s E rr n x o ffs e t( )

a rg x( )

2 o ffs e t

C n n( ) 3 K H z

January 2007

Ivan Reede Reede

Slide 99

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Let– “X” be the signal received through the channel

Q 6 4 E rr n( ) Q A M 6 4 X E rr n( )( )


January 2007

Ivan Reede Reede

Slide 100

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Let “Cycles” be the number of cycles – skipped by the QAM64 demodulator – from the sampling aperture start – to the moment separating the guard from the symbol

C y c le s E rr( ) C y c le s0

0

C y c le s1

0

k C y c le sn 1( )

k k 1( )( )

R e s E rr n Q 6 4 E rr n( ) k( ) R e s E rr n 1( ) Q 6 4 E rr n 1( )( ) C y c le sn 1( )

1

2 C n n( ) 3 K H zw h ile

C y c le sn

k

n 2 1 2fo r

C y c le s


January 2007

Ivan Reede Reede

Slide 101

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Let– “Rec” be the sampling aperture window start to the

guard to symbol transition moment Recovered Error value resolved by the geolocator algorithm

R E c E rr n( ) R e s E rr n Q 6 4 E rr n( ) C y c le s E rr( )n


January 2007

Ivan Reede Reede

Slide 102

doc.: IEEE 802.11-07-0111-00-000v

Submission

• Let– “graph” be the difference between the

• recovered error between the sampling aperture window start to the guard to symbol transition moment

– and the• theoretical value of this error

– “graph” will be plotted versus “Err”

g ra p h E rr n( ) E r r R E c E rr n( )


January 2007

Ivan Reede Reede

Slide 103

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results

• Perfect channel results• 802.22 Channel A results• 802.22 Channel B results• 802.22 Channel C results• 802.22 Channel D results

January 2007

Ivan Reede Reede

Slide 104

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation ResultsPerfect Channel

X E rr n( ) e 2 j C n n( ) 3000 H z E rr( )

FFT Output

January 2007

Ivan Reede Reede

Slide 105

doc.: IEEE 802.11-07-0111-00-000v

Submission

Perfect channel resultsTracking error for carrier 9 of 9: 3,6,12,24,48,96,192,384,768 kHz

1 0

1 0

c g rap h E rr 9( )

01 0 0 0 c E rr

m

1 0 0 0 9 5 0 9 0 0 8 5 0 8 0 0 7 5 0 7 0 0 6 5 0 6 0 0 5 5 0 5 0 0 4 5 0 4 0 0 3 5 0 3 0 0 2 5 0 2 0 0 1 5 0 1 0 0 5 0 01 0

9

8

7

6

5

4

3

2

1

0

1

2

3

4

5

6

7

8

9

1 0Q A M -6 4 d e m o d u a lt o r a lg o r it h m re s o u t io n

January 2007

Ivan Reede Reede

Slide 106

doc.: IEEE 802.11-07-0111-00-000v

Submission

Perfect channel resultsTracking error for carrier 9 of 9: 3,6,12,24,48,96,192,384,768 kHz

1 0

1 0

c g rap h E rr 9( )

01 0 0 c E rr

m

1 0 0 9 5 9 0 8 5 8 0 7 5 7 0 6 5 6 0 5 5 5 0 4 5 4 0 3 5 3 0 2 5 2 0 1 5 1 0 5 01 0

9

8

7

6

5

4

3

2

1

0

1

2

3

4

5

6

7

8

9


January 2007

Ivan Reede Reede

Slide 107

doc.: IEEE 802.11-07-0111-00-000v

Submission

Perfect channel resultsTracking error for carrier 10 of 10: 3,6,12,24,48,96,192,384,768,1536 kHz

1 0

1 0

c g rap h E rr 1 0( )

01 00 c E rr

m

1 00 9 5 9 0 8 5 8 0 7 5 7 0 6 5 6 0 5 5 5 0 4 5 4 0 3 5 3 0 2 5 2 0 1 5 1 0 5 01 0

9

8

7

6

5

4

3

2

1

0

1

2

3

4

5

6

7

8

9


January 2007

Ivan Reede Reede

Slide 108

doc.: IEEE 802.11-07-0111-00-000v

Submission

Perfect channel resultsTracking error for carrier 11 of 11: 3,6,12,24,48,96,192,384,768,1536, 3072 kHz

1 0

1 0

c g rap h E rr 11( )

01 00 c E rr

m

1 00 9 5 9 0 8 5 8 0 7 5 7 0 6 5 6 0 5 5 5 0 4 5 4 0 3 5 3 0 2 5 2 0 1 5 1 0 5 01 0

9

8

7

6

5

4

3

2

1

0

1

2

3

4

5

6

7

8

9


January 2007

Ivan Reede Reede

Slide 109

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results ConclusionPerfect Channel

• Simulation confirms expected resolution results• Simulation algorithm confirms the process works• That it can be effected by a programmed process• Even with the QAM64 demodulator's quantization• Therefore

– MAC access to the FFT output is not needed– All that is needed is an echo function– With channel estimator corrections OFF

• The entire processing can be done “offline”– The CPE need not do the processing– All the processing can be done by the BS geolocator

January 2007

Ivan Reede Reede

Slide 110

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation ResultsChannel A

1

d B 0( ) d B 7 .5( ) d B 1 5( ) d B 2 2( ) d B 2 4( ) d B 1 9( )0 .5 3 9

X E rr n( ) .5 3 9 d B 0( ) e 2 j C n n( ) 300 0 H z E rr 0 s( )

d B 7 .5( ) e 2 j C n n( ) 300 0 H z E rr 3 s( )

d B 1 5( ) e 2 j C n n( ) 300 0 H z E rr 8 s( )

d B 2 2( ) e 2 j C n n( ) 300 0 H z E rr 11 s( )

d B 2 4( ) e 2 j C n n( ) 300 0 H z E rr 13 s( )

d B 1 9( ) e 2 j C n n( ) 300 0 H z E rr 21 s( )

FFT Output

January 2007

Ivan Reede Reede

Slide 111

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel A resultsChannel Response State Trajectory For All 2000 Possible Carriers

1

1

Im X E rr n( )( )

11 R e X E rr n( )( )1 0 .75 0 .5 0 .25 0 0 .25 0 .5 0 .75 1

1

0 .75

0 .5

0 .25

0

0 .25

0 .5

0 .75

1

January 2007

Ivan Reede Reede

Slide 112

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel A resultsFrequency amplitude response for 12 selected pilots

1

0

X A 0 n( )

130 n0 1 2 3 4 5 6 7 8 9 10 11 12 13

0

0 . 2 5

0 . 5

0 . 7 5

1

January 2007

Ivan Reede Reede

Slide 113

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel A resultsTracking error for carriers 9,10,11 of 11: 3,6,12,24,48,96,192,384,768,1536, 3072 kHz

5 0

5 0

c g rap h E rr 9( )



01 00 0 c E rr

m

1 00 0 9 50 9 00 8 50 8 00 7 50 7 00 6 50 6 00 5 50 5 00 4 50 4 00 3 50 3 00 2 50 2 00 1 50 1 00 5 0 05 0

4 5

4 0

3 5

3 0

2 5

2 0

1 5

1 0

5

0

5

1 0

1 5

2 0

2 5

3 0

3 5

4 0

4 5


January 2007

Ivan Reede Reede

Slide 114

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results ConclusionChannel A

• Simulation confirms expected resolution results• Simulation algorithm confirms the process works• Despite the channel's multipath signal propagation• Results are much better than required

January 2007

Ivan Reede Reede

Slide 115

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation ResultsChannel B

1

d B 6( ) d B 0( ) d B 7( ) d B 2 2( ) d B 1 6( ) d B 2 0( )0 .4 3 7

X B E rr n( ) .4 3 7 d B 6( ) e 2 j C n n( ) 300 0 H z E rr 3 s( )

d B 0( ) e 2 j C n n( ) 300 0 H z E rr 0 s( )

d B 7( ) e 2 j C n n( ) 300 0 H z E rr 2 s( )

d B 2 2( ) e 2 j C n n( ) 300 0 H z E rr 4 s( )

d B 1 6( ) e 2 j C n n( ) 300 0 H z E rr 7 s( )

d B 2 0( ) e 2 j C n n( ) 300 0 H z E rr 11 s( )

FFT Output

January 2007

Ivan Reede Reede

Slide 116

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel B resultsChannel Response State Trajectory For All 2000 Possible Carriers

1

1

Im X E rr n( )( )

11 R e X E rr n( )( )1 0 .75 0 .5 0 .25 0 0 .25 0 .5 0 .75 1

1

0 .75

0 .5

0 .25

0

0 .25

0 .5

0 .75

1

January 2007

Ivan Reede Reede

Slide 117

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel B resultsChannel Response State Trajectory Carrier Selection Trimming

Carriers landinginside the blue amplitude circlesare trimmed off bythe ranging processvia 64-QAM_set analysis

1

1

Im X E rr n( )( )

Im T rim k( )( )

11 R e X E rr n( )( ) R e T rim k( )( )1 0 .75 0 .5 0 .25 0 0 .25 0 .5 0 .75 1

1

0 .75

0 .5

0 .25

0

0 .25

0 .5

0 .75

1

January 2007

Ivan Reede Reede

Slide 118

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel B resultsFrequency amplitude response for 12 selected pilots

1

0

X B 0 n( )

130 n0 1 2 3 4 5 6 7 8 9 10 11 12 13

0

0 .2 5

0 .5

0 .7 5

1

January 2007

Ivan Reede Reede

Slide 119

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel B resultsTracking error for carriers 9,10,11,12: 3,6,12,24,36,60,78,360,1050,2700, 5400,5940 kHz

5 0

5 0

c g rap h E rr 9( )




01 00 0 c E rr

m

1 00 0 9 50 9 00 8 50 8 00 7 50 7 00 6 50 6 00 5 50 5 00 4 50 4 00 3 50 3 00 2 50 2 00 1 50 1 00 5 0 05 0

4 5

4 0

3 5

3 0

2 5

2 0

1 5

1 0

5

0

5

1 0

1 5

2 0

2 5

3 0

3 5

4 0

4 5


January 2007

Ivan Reede Reede

Slide 120

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results ConclusionChannel B

• Simulation confirms expected resolution results• Frequency agility allows for null pilot frequencies• Simulation algorithm confirms the process works• Despite the channel's multipath signal propagation

– Mitigated by simple “specified Tone_Set” selection process

• Results are much better than required

January 2007

Ivan Reede Reede

Slide 121

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation ResultsChannel C

1

d B 9( ) d B 0( ) d B 1 9( ) d B 1 6( ) d B 2 4( ) d B 1 6( )0 .5 4 1

X C E rr n( ) .5 4 1 d B 9( ) e 2 j C n n( ) 3000 H z E rr 2 s( )

d B 0( ) e 2 j C n n( ) 3000 H z E rr 0 s( )

d B 1 9( ) e 2 j C n n( ) 3000 H z E rr 5 s( )

d B 1 6( ) e 2 j C n n( ) 3000 H z E rr 16 s( )

d B 2 4( ) e 2 j C n n( ) 3000 H z E rr 24 s( )

d B 1 6( ) e 2 j C n n( ) 3000 H z E rr 33 s( )

FFT Output

January 2007

Ivan Reede Reede

Slide 122

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel C resultsChannel Response State Trajectory For All 2000 Possible Carriers

1

1

Im X E rr n( )( )

11 R e X E rr n( )( )1 0 .75 0 .5 0 .25 0 0 .25 0 .5 0 .75 1

1

0 .75

0 .5

0 .25

0

0 .25

0 .5

0 .75

1

January 2007

Ivan Reede Reede

Slide 123

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel C resultsFrequency amplitude response for 12 selected pilots

1

0

X C 0 n( )

130 n0 1 2 3 4 5 6 7 8 9 10 11 12 13

0

0 .2 5

0 .5

0 .7 5

1

January 2007

Ivan Reede Reede

Slide 124

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel C resultsTracking error for carriers 9,10,11: 3,6,12,24,48,96,192,384,768,1536, 3072 kHz

6 0

6 0

c g rap h E rr 9( )



01 00 0 c E rr

m

1 00 0 9 50 9 00 8 50 8 00 7 50 7 00 6 50 6 00 5 50 5 00 4 50 4 00 3 50 3 00 2 50 2 00 1 50 1 00 5 0 06 0

5 4

4 8

4 2

3 6

3 0

2 4

1 8

1 2

6

0

6

1 2

1 8

2 4

3 0

3 6

4 2

4 8

5 4


January 2007

Ivan Reede Reede

Slide 125

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results ConclusionChannel C


January 2007

Ivan Reede Reede

Slide 126

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation ResultsChannel D

1

d B 1 0( ) d B 0( ) d B 2 2( ) d B 1 8( ) d B 2 1( ) d B 3 0( )0 .6 0 9

X D E rr n( ) .6 0 9 d B 1 0( ) e 2 j C n n( ) 3000 H z E rr 2 s( )

d B 0( ) e 2 j C n n( ) 3000 H z E rr 0 s( )

d B 2 2( ) e 2 j C n n( ) 3000 H z E rr 5 s( )

d B 1 8( ) e 2 j C n n( ) 3000 H z E rr 16 s( )

d B 2 1( ) e 2 j C n n( ) 3000 H z E rr 22 s( )

d B 3 0( ) e 2 j C n n( ) 3000 H z E rr 60 s( )

FFT Output

January 2007

Ivan Reede Reede

Slide 127

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel D resultsChannel Response State Trajectory For All 2000 Possible Carriers

1

1

Im X E rr n( )( )

11 R e X E rr n( )( )1 0 .75 0 .5 0 .25 0 0 .25 0 .5 0 .75 1

1

0 .75

0 .5

0 .25

0

0 .25

0 .5

0 .75

1

January 2007

Ivan Reede Reede

Slide 128

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel D resultsFrequency amplitude response for 12 selected pilots

1

0

X D 0 n( )

130 n0 1 2 3 4 5 6 7 8 9 10 11 12 13

0

0 .2 5

0 .5

0 .7 5

1

January 2007

Ivan Reede Reede

Slide 129

doc.: IEEE 802.11-07-0111-00-000v

Submission

Channel D resultsTracking error for carriers 9,10,11: 3,6,12,24,48,96,192,384,768,1536, 3072 kHz carriers

3 0

3 0

c g rap h E rr 9( )



01 00 0 c E rr

m

1 00 0 9 50 9 00 8 50 8 00 7 50 7 00 6 50 6 00 5 50 5 00 4 50 4 00 3 50 3 00 2 50 2 00 1 50 1 00 5 0 03 0

2 7

2 4

2 1

1 8

1 5

1 2

9

6

3

0

3

6

9

1 2

1 5

1 8

2 1

2 4

2 7


January 2007

Ivan Reede Reede

Slide 130

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results ConclusionChannel D


January 2007

Ivan Reede Reede

Slide 131

doc.: IEEE 802.11-07-0111-00-000v

Submission

Simulation Results Conclusion

• Simulation confirms expected resolution results• Frequency agility allows for null pilot frequencies• Simulation algorithm confirms the process works• Complies to functional requirements document

– In all 802.22 test channels: A, B, C and D

• Despite channel multipath signal propagation• Results are much better than required

January 2007

Ivan Reede Reede

Slide 132

doc.: IEEE 802.11-07-0111-00-000v

Submission

It is proposed

• That the standard requires all Station's include – Upon request by the AP– The return by the Station to the AP

• Of the 64-QAM output set

– Station emission of pilot tones • As specified by the AP to the Station

– At the moment specified by the AP• Down to the standard specified sampling clock granularity• With a maximum Rx to Tx jitter

– of “TBD” nanoseconds

• With a delcaration of Rx to Tx alignment – to “TBD” nanoseconds precision

doc.: ieee 802.11-07-0111-00-000v submission january 2007 ivan reede reede slide 1 ranging and...

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