Wireless E911 Overview and Status Update
David WoodcockDirector, Product Management
Motorola Canada PCS
FCC E911 MandateThis year*• 100m accuracy for 67% of calls• 300m accuracy for 95% of calls
Phase 2*• 50m accuracy for 67% of calls• 150m accuracy for 95% of calls
Subscriber Activations*• Certain % of new adds must be location-capable
*Exact dates and mandate vary by carrier
Position Determination OptionsPosition Determination OptionsNetwork-Based Assisted GPS
• Technologies– TDOA (3 sites minimum)– AOA (2 sites minimum)– Multipath “Fingerprint” (1
site minimum)• New site equipment• Legacy handset are
supported
• Handset modifications– Memory– A-GPS Integrated Chip Sets– Second Antenna– Software
• 1 site + 3 GPS Sat solution• New network boxes• Legacy handsets not
supported
ServingCell
NeighborCell # 1
NeighborCell # 2
MS
Wideband orScanningReceivers
LocationCalc & Control
GPSAssist
E-OTD/AFLT
ServingCell
NeighborCell # 1
NeighborCell # 2
MSSynchronizedSites or LMU’s
• Handset modifications– Software– Memory
• TDOA (3 sites minimum)• May require new site
equipment & network boxes• Legacy handsets not
supported
ServingCell
MS
LocationCalc & Control
GPSSat
How they compare
MLCMLC
MLCMLC
Increase in Accuracy
Increase in Coverage (Dense Urban, Valleys, Indoors)
Increase
Accuracy
Cell ID EOTD, AFLT GPS (Auto) A-GPS (Assist)
HS Changes None Software SW + HW SW + HWAdded Cost None Low High HighAccuracy 100-1000 m (Cell) 75- 300 m 15-150 m 1-100 m TTFF < 5 Sec 5-20 Sec 10-60 Sec <5 Sec
Hybrid: EOTD / AFLT
Network sends a burst message to the handset
Handset calculates time differentials & reports back.
Network calculates handset position
Hybrid: AGPS
GPS
Assistance data
Network provides assistance data to handset to limit satellite acquisition times.
Handset receives GPS data from satellites (three required for position determination)
Handset reports ‘pseudo-ranges’ to network for position determination.
Pseudo-ranges
Network calculates handset position
Handset vs. Network Based
• Pros– Minimum Network Impact– Greater Subscriber Privacy?– Proven High Degree of
Accuracy Using GPS– Less network maintenance
• Cons– Legacy Issue
– Handset size, cost, battery life
– GPS antenna issues
• Pros– Ability to Deploy
on an as Needed Basis
– Addresses Legacy Phones and Roamers
• Cons– More Site Antennas or new sites may
be Required in Some Areas
– Additional Equipment At Cell Site
– Large Initial Capital Requirement
– Calibration and additional maintenance
Handset Network
U.S. Carrier Plan of Record
Carrier MA Location TechnologyGSM E-OTD
TDMA/GSM Network / E-OTDTDMA/GSM Network / E-OTDCDMA2000 AGPS/AFLTCDMA2000 AGPS/AFLTCDMA2000 AGPS/AFLT
iDEN AGPS
U.S. Carriers have selected handset-based solutions
Motorola Handset RoadmapGSM/GPRS• Several EOTD-capable products launching in
2H02• All future products will have EOTD
CDMA/1X• One AFLT handset launching in June• Three AGPS handsets launching in 2H02• All future products will have AGPS
Multiple hardware and software solutions available for EOTD / AGPS
Then What?
Carrier network must calculate and report location to PSAP
“Push” – if location information is available at call-setup
“Pull” – if not available initially, or to update location information during call
PSAPs must be ready to integrate ALI from wireless devices
Issues…Relevance
– Does the (mobile) location data have any meaning?– How current is it? (street addresses can’t move…)
Accuracy– Performance in urban and rural areas– Satellite acquisition / multi-path signals– Cell site separation
Privacy– Do users really want to be found?– Users have ability to disable location service except during
911 calls
The challenge goes beyond technology
Handset capabilities are just the foundation
Network location determination
PSAP capabilities
Handset location capabilities
Data Usefulness
Many bricks needed to build the structure
Thank you
www.motorola.ca
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