The development of fundamental technologies supporting FeliCa began in 1988 after a major logistics firm approached Sony to develop an IC card system that would make the automatic sorting of packages a reality. Initially the developers decided to create a system that would use wireless technology to transmit unique IDs assigned to each package. The sorting system would read these IDs and sort packages by destination.
However, when a prototype tag capable of transmitting an ID was first engineered, the developers found that it would require not only an IC chip but also a thin laminated battery to supply power, as well as an antenna and various other components. The total cost was over 2,000 yen per unit. At this price, the tag would not have been suitable for use in managing a logistics environment where thousands of items need to be tracked. So, Sony was forced to abandon the idea of using the technology in a sorting system based on IC cards.
However, Sony continued to develop IC cards based on wireless technology. A key priority was solving the power supply problem, which had frustrated efforts to develop a logistics system for package deliveries. The CPU on an IC card needs electric power to operate, but a thin laminated battery would be too expensive. So Sony's engineers decided to use a reactive transmission system based on field-effect transistors (FETs), which have minimal power requirements.
Conventional transistors establish circuits by controlling the current outflow in relation to the input current. As long as conventional transistors are used, the circuits only exist while power is present. However, FETs produce signals by varying the input voltage. This allows them to establish operating circuits with infinitesimal amounts of power. With FET technology, it is possible to transmit data simply by modifying the resistance.
Today's FeliCa card has no battery, but at the time, the card still required an internal power source. However, these new advances opened the doors to development of an IC card that would operate using far less power than the original system design. The adoption of the FET approach in analog circuitry was a major step forward to the practical implementation of the FeliCa concept.
The development of FeliCa reached a major turning point in 1988. In that year, we learned that the JR Group's Railway Technical Research Institute was conducting studies on a ticketing system based on the use of IC cards. We thought it might be possible to use Sony's IC card technology in such a system, so we presented the Railway Technical Research Institute with our technological findings. However, the specifications required by the Institute were higher than we anticipated. They wanted a system capable of processing 60 people through a ticket gate per minute and a transmission time of 200ms or lower. The IC card we were developing at the time would not have been able to meet these requirements.
Another requirement stipulated by the Railway Technical Research Institute was that the IC card must operate without a battery. We had succeeded in reducing the card's power consumption, but we had not developed a totally batteryless card. However, we were aware that the number of cards used by a full-scale ticketing system adopted by the JR Group would be extremely large. Both JR and Sony reached the conclusion that a card without an internal power supply would be the ideal solution. This conclusion was based not only practical considerations, such as thickness and battery life, but also on environmental considerations, including the need to avoid the release of toxic substances at the time of disposal. Our first step toward the creation of a batteryless card was to switch to non-volatile memory (EPROM). By using the 13.56MHz frequency, on which it is legally permissible to transmit electric power, we were able to create a system capable of supplying power from the reader/writer without contact. The advantages of an IC card based on FET technology now became apparent. Because Sony had reduced the power requirements of its IC card by using FETs, it was relatively easy to create a card without an internal power supply.
The effective distance stipulated for radio waves emitted by an IC card is at least 10cm and no more than 20cm. Ticket gates are used by large numbers of people, and the system must be able to recognize IC cards held 10cm or more from a read/writer while still allowing people to pass through smoothly. If the radio waves are too strong, transmissions emanating from one IC card interfere with transmissions from another person's IC card being used at an adjacent ticket gate leading to erroneous charging. To prevent this, the maximum distance for the transmission of radio waves is 20cm. The FeliCa technology developed to meet these requirements was used in the "Suica" card, which was introduced by East Japan Railway on November 18, 2001. Initially there were problems caused by uncertainty about the way the cards should be used. For example, people held their cards too far away from the reader/writers or kept their Suica cards in wallets with other IC cards. Many of these problems resulted from the fact that this was Japan's first contactless ticketing system and was unfamiliar not only to users, but also to those operating the system. We had to assign specialist staff around the clock to deal with these issues. I was one of them and for about two years after the introduction of the technology, I had to be ready to deal with problems, even on New Year's Day.
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