Do aircraft have radar or other forms of traffic sensing?
By far, most civil aircraft lack radar to display conflicting traffic, and certainly to enhance traffic situational awareness.  TCAS and the use of ADS-B are the most effective tools for traffic conflict and situational awareness information.

Lidar is not presently utilized on civil aircraft for traffic avoidance. 

Keep in mind that TCAS essentially uses the same mechanisms as secondary ATC radar.