Special Sensor

Question

Are there any hardware solutions or something, where I can start, for the task I describe here? For example, I have a smartphone with a built-in camera and a special sensor attached (the first hardware device I'm looking for) that "looks" in the same direction as the camera. Next, there is a human in front of me (may be in 3-10 meters). He has a special sensor that is connected to his smartphone and he has an ID number (the second hardware device I'm looking for). Now I aim my camera on this human and the sensor in my smartphone catches the signal sent by that human's sensor. So now I can use my software to identify the man that I see through my camera by ID from his sensor.

Actually, in my opinion, this imagined system doesn't need camera at all. The camera is just a helper tool. For example, if I have no camera but have sensors, I can aim and catch the human in the dark night. If I there two or ten people around me with sensors in their phones, I can see info about them on screen and see their locations relatively to me. I imagine that if a lot of people have phones with such built-in sensors and registered accounts at the system, they can share some info with passer-by if they want. It's something like augmented reality, not for objects around you, but for people. Thank you.

Answer 1

Active RFIDs with directional antennas?

A little more far out, but if people are willing... stick him with an implant

Answer 2

Bluetooth?

Answer 3

Some of the augmented reality toolkits can do something similar without needing separate sensors. Take a look at the ARToolkit. The demos I've seen might use a shorter range than you want, but it is all camera based.

Answer 4

Something like shotcode?

Diego López de Ipiña , Paulo R. S. Mendonça , Andy Hopper, TRIP: A Low-Cost Vision-Based Location System for Ubiquitous Computing, Personal and Ubiquitous Computing, May 2002

Answer 5

I am responding regarding your idea with the use of Bluetooth. I am developing a BT sensor for proximity. I am using the old Bluetooth technology (BT 2.1). Not using the new BT 4.0 low energy standard - and new chips - althou the new standard has a proximity profile.

I have finally found a proximity algorithm for the old Bluetooth technology (it is not entirely acurate, but will work for a commercial application).

Regarding your project, Bluetooth will detect some proximity, but will not detect at all direction! I mean it even detects proximity through car parking walls!!

So, reply if you think you could still use it Bluetooth.