Automated Real-Time Intelligent Traffic Control System for Smart Cities Using Wireless Sensor Networks

Table 1

Comparison between the different types of most used sensors.

	Magnetic sensor	Light sensor	Ultrasonic sensor
Advantages	(i) Low cost (20-120 €); (ii) Range greater; (iii) Reacts to north pole and south pole; (iv) Insensible to vibrations; (v) Best detection of cars	(i) Average cost (60-300 €); (ii) Large range (1 m); (iii) Insensible to vibrations and no wear; (iv) Detects any type of room with reflective power (direct reflection mode)	(i) Large range (15 m); (ii) Detect without contact with any object (whatever the material); (iii) Adjustable sensitivity
Limitations	(i) Average range (<300 mm); (ii) Requires the use of a magnet; (iii) Sensitive to electromagnetic disturbances	(i) Supports badly the harsh environments; (ii) Sensitive to the appearance of parts (material, surface condition, color, gloss, impact, etc.)	(i) High cost (200-1000 €); (ii) Sensitive to drafts; (iii) Sensitive to temperature