Wsn specification

Parking system structure

Nodes

• Are battery operated, sensing the presence of vehicle and send data wireless
• The battery is calculated to last for 5 years of operation
• Vehicle sensing by measuring the earth magnetic field disturbance
• RF communication based on IEEE 802.15.4 at 2.4 GHz
• Create automatically a self-healing mesh network.

Parameters and Network behavior can be reconfigured over-air

Data from Nodes not in range of Repeater can be 'Bridged' from neighbor-Nodes

The destruction of a Bridge-Node does not disturb the Self-Healing-Network

Network is re-arranged automatically

• Transmit data typically every 3.5 minutes(Configurable over air from 1 minute )
• Sense the magnetic field disturbance created by a vehicle standing over them

The sensed data are taken typically every 60 seconds (Configurable over air ) and recorded for transmission.

• Mean current consumption is kept low:

• Transmitting the data very fast (250ms)
• Using Ultra Low Power 'Sleep' mode between transmissions
• Further reduction of energy consumption:

Increasing the Period from the typical 3 minutes to hour(s) for the no-traffic hours (might be at night)

Configurable over air

Repeaters

There are one or more Repeaters in the system

• Participate in the mesh-network as non-sleeping nodes
• The RF power and range is higher than Nodes

• Repeaters transfer data between:

Concentrator and Nodes

Repeater to Repeater

• Supplied by re-chargeable battery and a small Solar Panel

Concentrator

There is one concentrator in the system

• Concentrates Data from Nodes via the Repeaters
• If needed changes the parameters of:

Network

Repeaters

Nodes

• Communicates with Repeaters via RF
• Depending on system configuration, can include:

• PC
• Industial PC
• Ethernet connection
• GSM connection

• Supplied by mains