Broadband small size antenna for W-band chip-to-chip communication system

Abstract

Multi-function, high data rate, low power, and small size. This trend has leaded the electrical engineer-ing for the last two decade, and mainly the improvement of the silicon process has made it possible. The world market in smartphones has accelerated the competition between the smartphone companies, and it also made customers’ demand go higher. For multiple functions, many chips should communicate each other. For the high data rate, chips should transfer lots of data at a time. Traditionally, metallic lines have been used for the interconnection between chips on PCBs, such as FR4, Duroid, and so on. But one lane has the bandwidth limitation, and it means that many parallel lines are needed for the high data rate between two chips. This causes the circuit complexity, the power loss, and the serious cross talk because many lines should be all in the limited area on a PCB. Many study groups have been researching on wireless interconnections as the alternatives to solve the problems of the wire interconnections. Optical interconnection is one of the popular methods to interconnect wirelessly between chips due to its benefits, such as the wide bandwidth and the high power efficiency. But it is not proper to the commercialization due to the high cost and the inability of integrating laser sources into silicon wafers. RF coupling interconnection, such as a capacitive coupling method, has the characteristics of the wide bandwidth and the low power consumption. But it can be used only in the very short distance (~um) and the vertical arrangement of chips. However, RF wireless communication using antennas is suitable for the chip-to-chip communication in a distance of 10cm in terms of the reasonable energy efficiency and the wide bandwidth. Especially, using the millimeter-waves, the wide bandwidth can be achieved more easily and the antenna size can be reduced smaller than in other low frequencies. Antennas are the key block for the RF wireless chip-to-chip communic...