An ASK transmitter and receiver chipset using 40 nm CMOS technology for wireless communication systems is described, in which a maximum data rate of 10 Gbps and power consumption of 98.4 mW are obtained with a carrier frequency of 135 GHz. A simple circuit and a modulation method to reduce power consumption are selected for the chipsets. To realize multi-gigabit wireless communication, the receiver is designed with consideration of the group delay optimization. Keywords: CMOS, ASK, millimeter-wave, D-band Introduction Recently, multi-gigabit wireless communication systems using millimeter-waves have attracted considerable attention. Transmitter (TX) and receiver (RX) ICs based on CMOS, which has the ability to realize such circuits with low power consumption and a low cost, are expected to become widespread [1,2]. The use of complex modulation methods makes it possible to achieve a higher data rate, but they also dissipate a large amount of power [3]. An amplitude shift keying (ASK) modulation method can be realized using simple circuits with low power consumption [4]. However, ASK transceivers require a wide frequency bandwidth. Although many LSIs in the 60 GHz band have been developed, a bandwidth of only 9 GHz is available. The frequency range above 100 GHz has attracted attention, because it is possible that a wide frequency range of over 10 GHz can be used for wireless communication systems [5]. In this work, an ASK TX and RX chipset with a carrier frequency of 135 GHz using 40 nm CMOS technology is described. In the following sections, the circuit design and measurement results are reported.
135GHz ASK Transceiver Design
A. Proposed transceiver and Target Frequency BandWe first had to choose a suitable frequency band since no standards have yet been established for wireless communication in the D-band. Figure 1 shows a block diagram of the proposed D-band ASK transceiver and Fig. 2 shows the operation frequency target. The ASK transceiver has a simple circuit architecture with low power consumption. However, an ASK transceiver with a high data rate requires a wide frequency band. There are some frequency bands in the D-band allocated exclusively to passive applications, such as radio astronomy and earth exploration satellites, based on the International Telecommunication Unions Radiocommunication Sector (ITU-R). The operation frequency of the proposed TX and RX is selected while avoiding these frequency bands, and the target frequency is between 116 GHz and 148 GHz. The TX chip consists of an oscillator (OSC) and an ASK modulator [6]. The RX chip consists of a low noise amplifier (LNA), a detector, limiting amplifiers with DC offset cancellers and a buffer [7,8].
B. Transmitter DesignTo reduce the power consumption of the D-band TX, a power-amplifier-free topology is adopted. Figure 3 shows a circuit schematic of the TX and the simulation results of the optimum load with contour plot of output power of the OSC. The fundamental oscillation frequency of the OSC is half of the target output frequency, thus, a ...