Yue’s Yappings

My friend Alan has a software company that writes software for casinos in Hong Kong. Right now he is thinking about using RFID in casinos. There are several applications. One is card authentication. It helps prevent one form of cheating where players hide their own cards in their sleeves. By using cards with embedded RFID chips the dealer can authenticate each card on the table instantly.

Another application is counting chips. Imagine sitting at a poker table and one of the players goes all in - you need to find out how much it is to call. If a RFID tag is embedded in each casino chip then the table can automatically tell you.

Most people have a misconception that RFID tags can be read across a room. The truth is there are two type of tags, HF and UHF.  HF tags has read range of few inches, and  UHF tag have the read range of a few meters.  A small UHF RFID tag in a size of Poker chip has a maximum range of 2 or 3 meters (less than 10 feet), which is just enough for a dealer at a table to scan the cards and chips.

Another limitiation is that most RFID readers can only read one tag at a time. To read multiple tags requires higher end readers that support anti-collision technology. So in order to scan multiple poker chips at once, the reader must support anti-collision.