Renesas Electronics developed of new technology that realizes a close proximity wireless communication over very short distances of a few centimeters, in which a compact antenna can be integrated with the transmitter and receiver circuit blocks in a single chip.
The new technology can eliminate the metal connector in small equipment such as memory cards and/or wires in hinges of mobile terminal devices, where contactless communication has been difficult to realize.
Renesas Electronics has also developed a prototype transceiver chip with an integrated antenna employing this technology, confirming the availability of contactless data communication at a rate of 15 megabits per second (Mbps), which is comparable to the data rates required for high-definition terrestrial digital TV transmission.
The close proximity wireless communication technology is currently applied in contactless smartcards. However, problems still remain with the adoption of this technology for small equipment as they require a large antenna area of credit card size to achieve sufficiently small noise levels and/or large tolerance for misalignment between the transmitter chip and the receiver chip.
Renesas Electronics' newly developed contactless communication technology requires an antenna only 1 mm in diameter, which is small enough for on-chip integration, and enables short-range data transmission over a distance of 1 cm. By applying the new technology, the contactless communication interface on a flash memory card will not fail to achieve a wireless connection even at a misalignment of 1 cm. Moreover, the adoption of this interface technology can overcome issues such as unstable metal connections caused by moisture or abrasion.
The new technology uses a wireless architecture in which the transmitter sends the data signal and synchronization signal simultaneously. This architecture provides a higher noise-tolerance than conventional methods in which the receiver circuit and transmitter circuit each generate synchronization signals separately. This has made it possible to accept a position misalignment of even 1 cm between the transmitter circuit and receiver circuit, while reducing the size of the antenna to a few square millimeters, approximately one-hundredth the area previously required. In addition, the antenna as well as the transmitter and receiver circuit blocks can be integrated in a single chip.
The new technology can also eliminate the use of a large-sized, power-consuming PLL (phase locked loop) in the receiver, since the receiver does not need to generate a synchronization signal. This reduces the power consumption of the receiver by approximately 50 percent compared to conventional designs.
In addition to allowing for more compact products, the use of contactless connectors makes possible a higher level of communication quality assurance regardless of their usage environment. Furthermore, the use of a contactless communication interface for the docking cradle of devices such as slim mobile phones, smartphones, and mobile information terminal devices, provides advanced design flexibility.
Renesas Electronics believes the new technology will contribute to the development of compact and reliable networking devices.
Renesas Electronics presented the results of this research at the Symposium on VLSI Circuits, which was held in Honolulu, Hawaii from June 16 to June 18.