Trial begins on the use of satellite tracking in Singapore

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#11
(15-10-2012, 10:42 AM)WolfT Wrote:
(15-10-2012, 09:56 AM)yeokiwi Wrote: GPS is pretty useless in built-up areas. Normally, the phone tracks via either the telco 3G stations or wifi hotspots through triangulation.
Turning off GPS only reduces one source of location information.

GPS only works if u are in areas if you can see the sky. The rest of the covered up areas, u need to have internal coverage. Something like 3G yes but i doubt they are going to use the telco's equip due to security.
If are they are going to install new equip? Building all the infrastructure from scratch is no joke, meaning all the covered car parks , tunnels, expressways in sg.
Looks it would most pro be done by ST electronic again. (would they use neratel products?)

The method is already been used widely, the technology of Assisted GPS (A-GPS). No new infrastructure needed

From wikipedia

"Assisted GPS, generally abbreviated as A-GPS or aGPS, is a system which can under certain conditions improve the startup performance, or time-to-first-fix (TTFF), of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones"
“夏则资皮,冬则资纱,旱则资船,水则资车” - 范蠡
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#12
(15-10-2012, 11:01 AM)CityFarmer Wrote:
(15-10-2012, 10:42 AM)WolfT Wrote:
(15-10-2012, 09:56 AM)yeokiwi Wrote: GPS is pretty useless in built-up areas. Normally, the phone tracks via either the telco 3G stations or wifi hotspots through triangulation.
Turning off GPS only reduces one source of location information.

GPS only works if u are in areas if you can see the sky. The rest of the covered up areas, u need to have internal coverage. Something like 3G yes but i doubt they are going to use the telco's equip due to security.
If are they are going to install new equip? Building all the infrastructure from scratch is no joke, meaning all the covered car parks , tunnels, expressways in sg.
Looks it would most pro be done by ST electronic again. (would they use neratel products?)

The method is already been used widely, the technology of Assisted GPS (A-GPS). No new infrastructure needed

From wikipedia

"Assisted GPS, generally abbreviated as A-GPS or aGPS, is a system which can under certain conditions improve the startup performance, or time-to-first-fix (TTFF), of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones"

For indoor coverage,u need a cell enhancer to convert these signal to data then transfer to base station followed by exchange(singtel).
AGPS itself does not cover close areas like tunnels and underground carparks.Maybe multi story carparks ok.

From wiki
An AGPS capable device can connect to these servers and download this information using Mobile Network radio bearers such as GSM, CDMA, WCDMA, LTE or even using other wireless radio bearers such as Wi-Fi.

That is why I say LTA need new infrastructure for it to work. We cannot expect LTA to build a 3/4G network underground just for this.
But No infrastructure needed if LTA decides to uses current MHA existing network.(meaning to say share network with police/scdf)
The thing about karma, It always comes around and bite you when you least expected.
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#13
(15-10-2012, 12:17 PM)WolfT Wrote:
(15-10-2012, 11:01 AM)CityFarmer Wrote:
(15-10-2012, 10:42 AM)WolfT Wrote:
(15-10-2012, 09:56 AM)yeokiwi Wrote: GPS is pretty useless in built-up areas. Normally, the phone tracks via either the telco 3G stations or wifi hotspots through triangulation.
Turning off GPS only reduces one source of location information.

GPS only works if u are in areas if you can see the sky. The rest of the covered up areas, u need to have internal coverage. Something like 3G yes but i doubt they are going to use the telco's equip due to security.
If are they are going to install new equip? Building all the infrastructure from scratch is no joke, meaning all the covered car parks , tunnels, expressways in sg.
Looks it would most pro be done by ST electronic again. (would they use neratel products?)

The method is already been used widely, the technology of Assisted GPS (A-GPS). No new infrastructure needed

From wikipedia

"Assisted GPS, generally abbreviated as A-GPS or aGPS, is a system which can under certain conditions improve the startup performance, or time-to-first-fix (TTFF), of a GPS satellite-based positioning system. It is used extensively with GPS-capable cellular phones"

AGPS itself does not cover close areas like tunnels and underground carparks.Maybe multi story carparks ok.
You still need additional hardware for AGPS to work and it is not reliable.
For indoor coverage,u need a cell enhancer to convert these signal to data then transfer to base station followed by exchange(singtel).

Theoretically AGPS will work as long as mobile signals available. It is taking an assisting role over GPS. Well, i agree it is not 100% covered in all corners of Singapore

IIRC, AGPS is software-base application, worked on top of existing hardware.
“夏则资皮,冬则资纱,旱则资船,水则资车” - 范蠡
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#14
AGPS is simply used to quick start the GPS to first fix by providing GPS with current location, UTC time and probably supplying almanac and ephemeris data to the onboard gps.
With the information, GPS will be able to determine the satellites and their IDs that are currently in view with the GPS in open space.

It assists the GPS to quick start. If the GPS satellites are not present, it cannot do anything.

Normally, GPS downloads almanac and ephemeris through GPS satellites but the GPS bit rate is low and coupled with the need to lock-on to GPS signals, GPS initialization will take a long time.

Nowsaday, GPS receivers come with 12 or more channels(24?) and the lock-on time has already been reduced.
But, the communication bit rate is still too low and so for a cold start, 45 sec is probably the minimum.
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#15
I think it is premature to conclude that GPS satellite tracking will be used for the next generation ERP, based on this CNA report:
http://www.channelnewsasia.com/stories/s...68/1/.html

Quote:Trials under way for next generation ERP system
By Woo Sian Boon, TODAY | Posted: 09 October 2012 0649 hrs
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Last year, four consortia - Kapsch TrafficCom, MHI Engine System Asia and NCS, ST Electronics (Info-Comm Systems) and IBM Singapore, and Watchdata Technologies and Beijing Watchdata System - had won the tender to develop technologies to replace the current gantry system in a timeframe of 18 months.

The four consortia had also been allocated a seed fund of S$1 million each for the project and might include a satellite-tracking system.

In response to queries, the Land Transport Authority (LTA) said that the System Evaluation Test (SET) had begun in May and "is a technological trial to help identify a technological solution most suited for Singapore".

Notice in the CNA report, there is a picture of a slimmed down gantry, probably as part of the trials.
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