With coin-cell battery, BLE beacon can work up to years depending on the broadcasting frequency. On the other hand, GPS is traditionally thought to be power hungry. The power consumption of GPS is comparable with WiFi.

With respect to the location accuracy, GPS is born to implement the location service, whereas BLE is definitely not. BLE is mostly used to implement context-aware applications. The tricky part happens at indoor environments where GPS fails. In such situations, BLE may be used together with triangulation algorithms to locate objects. There is a company called Estimote who has done some work about the indoor location with BLE. You may find some location-accuracy data on their website.

Dear Jingtian 

Thank you for your answer.

Definitely, GPS was designed to fulfil location services requeriments. My questioning was made principally to search for an alternative to this power hungry  technology, BLE seems to be a good direction since the existing  indoor triangulation techniques can be used in outdoor context where BLE devices can be widely deployed (SmartCities). I don't think that triangulation algorithms using BLE devices are so bad in term of accuracy but i know that its suffer from problems like : 

In non-controlled environments, where you can find metals, and other objects that affect the signal, the received signal strength of the beacons changes so often that it seems impossible to get error range below 5 meters.

Depending on the way that the user is handling the receiver device, the readings can change a lot as well. If the user puts his/her hand over the bluetooth antenna, then the algorithm will have low signals as input, and thus the beacons will supposed to be very far from the device.

Best,

Well both have unique applications, completely depends on the business case + use case. Considering environments and costs.

a. BLE on Indoor works brilliantly and with the advent of 5.0 we should see more use cases evolving, including metal environments

b. Battery life can be a optimised depending on the read range and frequency

c. Rugged cases are available for both BLE and GPS Modules

Again a big disadvantage is building the MESH - If the nodes are less its still easier to manage but if the nodes are in 1000's the MESH becomes way to complicated to manage. A gateway is always needed to communicate with these BLE beacons, alternatively a Mobile device can be used (again depends on the use case)

Why the BUSINESS CASE is important

- One needs to build the business for a period of 3 years and account for the following costs

a. Connectivity - Any GPS module will demand GSM connectivity there is a recurring/ monthly or annual cost to this

b. MAP lics. this is again a cost and could be substantial depending on the use case (if its a commercial use of the MAP platform, you better have deep pockets)

c. Battery has always been an area of concern when it comes to using a GPS module and its surely a battery sucker.

With the GSM the data can directly be pushed on the cloud.