what is the difference between standard GPS and Mobile phone GPS???

[pradeep_k_b]

What is the difference between mobile phone GPS and standard GPS??....Which one is better???.

 

[tpetar]

Depends from many things.

My opinion, its better to have all in one, for us stadard users. You get phone and all is there navigation, phone, Internet,...

But GPS modules can have better quality of signal and external antenna, GPS module can be added to some project or some existing device.

 

[pradeep_k_b]

actually what is the difference between them??...I think in mobile phones there is no direct communication with the satellite??..then how it work???

 

[tpetar]

Receivers for the Global Positioning System must lock onto the signals from four of the GPS satellites to give a full three-dimensional position. More limited information can be gained from two or three satellites. Different types of receivers make use of different parts of the GPS Signal Structure.

The observable quantities are
1. The C/A code on carrier L1 (sufficient for +/-100 m positioning).
2. The P-code on carrier L1
3. The P-code on carrier L2
4. The phase of the L1 carrier
5. The phase of the L2 carrier

Handheld GPS Positioners
The most popular type of GPS receiver is a handheld positioning and navigation unit which monitors the C/A code on the L1 carrier of the GPS signal structure. Such units must be used outdoors with a clear view of the sky, and are capable of locking onto the signals from four or more GPS satellites. The signals allow them to calculate the distances to four satellites, and with that data they can calculate position on the earth's surface in latitude and longitude within +/- 100 meters 95% of the time. They can measure altitude to an accuracy of +/- 180 meters. Since the four signals received are stabilized by atomic clocks, the timing accuracy of an ordinary digital watch is sufficient for the calculations done in the handheld unit. Waypoints may be set and stored in the units, and the received signal used to calculate range and direction to those waypoints. Speed and direction of travel can also be displayed. This makes it clear why they have become extremely popular with hikers and hunters.

http://hyperphysics.phy-astr.gsu.edu/hbase/gpsrec.html#c1
http://hyperphysics.phy-astr.gsu.edu/hbase/gps.html

 

[pradeep_k_b]

okay thank you....But I think the GPS technology that used in the mobile phones have some difference from the standard GPS...I think mobile phones GPS depends the mobile phone towers too...Am I right??

 

[tpetar]

Standalone GPS provides first position in approximately 30–40 seconds. A Standalone GPS system needs orbital information of the satellites to calculate the current position. The data rate of the satellite signal is only 50 bit/s, so downloading orbital information like ephemeris and almanac directly from satellites typically takes a long time, and if the satellite signals are lost during the acquisition of this information, it is discarded and the standalone system has to start from scratch. In AGPS, the Network Operator deploys an AGPS server. These AGPS servers download the orbital information from the satellite and store it in the database. 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. Usually the data rate of these bearers is high, hence downloading orbital information takes less time.

"Standalone" or "autonomous" GPS operation uses radio signals from satellites alone. A-GPS additionally uses network resources to locate and use the satellites in poor signal conditions. In very poor signal conditions, for example in a city, these signals may suffer multipath propagation where signals bounce off buildings, or are weakened by passing through atmospheric conditions, walls, or tree cover. When first turned on in these conditions, some standalone GPS navigation devices may not be able to fix a position due to the fragmentary signal, rendering them unable to function until a clearer signal can be received continuously for a long enough period of time.

https://en.wikipedia.org/wiki/Assisted_GPS

 

[picgak]

okay thank you....But I think the GPS technology that used in the mobile phones have some difference from the standard GPS...I think mobile phones GPS depends the mobile phone towers too...Am I right??

Sattelite GPS is accurate were as mobile gps depends on tower location

 

[keith1200rs]

All GPS systems receive and decode data from satellites. Phones can lock quicker because they can also triangulate from the phone towers first.

The GPS chipsets in phones are pretty good nowadays.

Keith