We need to design a system for traffic congestion / smart parking that the input is at least three to four sensors. Choosing the sensors are very important from cost, installation, maintenance, performance, weather, and so on. Data acquisition is the next step, we need to know the output signal characteristics to design the correct one. We need one data acquisition for many sensors it is called multiplexing. Then we need to design the processing unit and communication. Focus on characteristics for the sensor. I am living in Seattle USA so I see the below sensors are suitable according to task 2.2 that I will attach. Please if you have a new list for 2015 and above for sensors costs please update it for me in task 2.2 in the table. I put it for 1999. I am trying to use traffic/video camera with a video image processor (first sensor) The second sensor is the Microwave radar sensor. The third one is the electrochemical sensor to measure the gases. The fourth one is GPS or Bluetooth to measure the travel time, and delay. The microcontroller is the best I think for processing units with Arduino microcontrollers because it is easier one. In the second proposal, Smart parking can use a camera sensor and maybe an ultrasonic and electrochemical sensor.