Antennas are rectangular, circular, and rod-shaped. Generally, the longer the communication distance is, the larger the size of the antenna. However, in actual use, when tags are attached to an item, even the RFID tags of the business card size are too large. In fact, the size and shape of the RFID tag in use need to be selected based on the communication distance.
Currently, antenna materials include aluminum, copper, and so on. The price of aluminum is cheaper than that of copper, but it has the disadvantage of difficult acidification. On the other hand, copper has the advantages of high transmission rate and micro-machining.
(Figure 5) (Tony Note: no corresponding image is found)
Figure 5 shows an example of an antenna with a bandwidth of 13.56mhz. As shown in the figure, there are various shapes of tags on the market for sale.
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