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3 Physical Theory of RFID System Physical Anti-Collision
Fig. 3.16 Salt mist
environment test chamber
Fig. 3.17 Entity diagram of
test chamber
The humidity sensor is suspended in the test chamber. The heater and humidifier,
connected to a humidity controller outside the test chamber, are placed on the bottom
of the test chamber. We set the experimental humidity of the humidity controller. The
humidifier and heater can be humidified or dehumidified as needed. The humidifier is
externally connected with different concentration of NaCl solution, and the humidification process is sprayed with NaCl solution inside the test chamber to achieve the
salt mist environment required for the experiment. When the hygrometer shows that
the humidity reaches 80%, the humidifier stops humidifying, forming an application
environment with certain humidity.
In order to simulate the salt mist environment for RFID tag reading experiments,
we designed an RFID dynamic measurement system. As shown in Fig. 3.18, the
experimental platform consists of the following parts: a control computer, a reader
antenna, a laser ranging sensor and other auxiliary equipment. The RFID dynamic
measurement system entity diagram is shown in Fig. 3.19.
When the test chamber enters the reading area, the antenna emits electromagnetic
waves to activate the tag, then the tag reflects the electromagnetic waves to transmit
the information in the tag, and the reader activates the laser ranging radar. Therefore,
the reading distance from the antenna to the tag can be calculated, the average of
multiple measurements is used for the reading distance of the antenna to tag.
3 Physical Theory of RFID System Physical Anti-Collision
Fig. 3.16 Salt mist
environment test chamber
Fig. 3.17 Entity diagram of
test chamber
The humidity sensor is suspended in the test chamber. The heater and humidifier,
connected to a humidity controller outside the test chamber, are placed on the bottom
of the test chamber. We set the experimental humidity of the humidity controller. The
humidifier and heater can be humidified or dehumidified as needed. The humidifier is
externally connected with different concentration of NaCl solution, and the humidification process is sprayed with NaCl solution inside the test chamber to achieve the
salt mist environment required for the experiment. When the hygrometer shows that
the humidity reaches 80%, the humidifier stops humidifying, forming an application
environment with certain humidity.
In order to simulate the salt mist environment for RFID tag reading experiments,
we designed an RFID dynamic measurement system. As shown in Fig. 3.18, the
experimental platform consists of the following parts: a control computer, a reader
antenna, a laser ranging sensor and other auxiliary equipment. The RFID dynamic
measurement system entity diagram is shown in Fig. 3.19.
When the test chamber enters the reading area, the antenna emits electromagnetic
waves to activate the tag, then the tag reflects the electromagnetic waves to transmit
the information in the tag, and the reader activates the laser ranging radar. Therefore,
the reading distance from the antenna to the tag can be calculated, the average of
multiple measurements is used for the reading distance of the antenna to tag.