Utilizing Wireless MAC Protocols for mitigating interference in 3D ToF Cameras
We make the following observation:
The current approach of stochastic slots and then doing collision detection, is a passive approach. A more active approach can be used.
Drawing inspiration from wireless CSMA-CA protocol, we propose to avoid collisions (whenever possible).
Additional Benefit - No Hidden Terminal Problems in MCI
We may not suffer from the Hidden Terminal problem in the MCI scenario.
Hidden Terminal Problem is a widely occuring cae of interference in wireless systems because transmitter is unaware of the channel state at receiver.
In MCI, transmitter-receiver are co-located!
Algorithm
At each slot
Sense the channel to see if it is busy
If channel is busy
Defer the current slot
Else
Transmit light and receive from the object post reflection
Employ collision detection to check if no camera interfered
Use the non clashed slots for depth estimation
Practical Considerations
We test the performance of the proposed protocol in a simulation. For the simulation to be as close as possible to the real-life scenarios, we also implement the following in our simulation:
Use of fractional slots for channel sensing and remaining slot for image capture.
Use of stochastic slots, even when the channel is found to be idle.
We discuss the detailed results and analysis in the Results and Discussion section.