Takahide Terada

Transceiver circuits for pulse-based ultra-wideband

In this paper a single chip CMOS front-end transceiver for ultra-wideband (UWB) radio is presented. This is the first paper to present whole transceiver circuits for pulse based UWB. The transceiver consists of mostly digital circuits except the LNA and mixer which are simulated for 0.18 /spl mu/m CMOS technology. The power consumption of LNA can be reduced by switching the bias current which is the advantage of the discontinuous feature of the pulse based UWB. The receiver design is tested against PVT variations by running Monte-Carlo simulations. As per the results, the power consumption of the transceiver is 0.44 mW at 10 Mpps (pulse per sec) and 2.5 mW at 50 Mpps.

A CMOS impulse radio ultra-wideband transceiver for 1Mb/s data communications and /spl plusmn/2.5cm range findings

A CMOS impulse radio ultra-wideband (IR-UWB) transceiver is developed in 0.18/spl mu/m CMOS. It can be used for a 1Mb/s data transceiver, as well as a range finder within an error of /spl plusmn/2.5cm. Chip layout area of a transmitter and a receiver is 0.035mm/sup 2/ and 0.38mm/sup 2/, respectively. Power dissipation for 1Mb/s data communications is 0.7mW for the transmitter and 4.0mW for the receiver. Bit error rate is lower than 10/sup -5/ for ranges of shorter than 95cm, and 10/sup -3/ for 1m distance. For use of the range finder, power dissipation of the transmitter is 0.7/spl mu/W for 1000 measurements per second. Electronic field intensity is lower than 35/spl mu/V/m, in compliance with the regulation for the extremely low power radio station. Digital transmitter and clocked correlator are proposed for reduction in both layout area and power dissipation.

Retrodirective transponder array with universal on-sheet reference for wireless mobile sensor networks without battery or oscillator

A rotating shaft in a wheel, a motor and a turbine uses sensors to measure torque, vibration, and acceleration for better control and maintenance of a machine. Such data is currently acquired in a laboratory and utilized for tuning the machine. For adaptive control and failure prognosis in future, the data need to be collected by the sensors on the fly. Connecting the moving sensors by wire and a brush to a microcontroller leaves reliability issues due to mechanical wear and electrical noise. A wireless data link with small form factor and low maintenance cost is needed. Bluetooth consumes large power and requires external parts such as a battery and a crystal. RFID loses connectivity when the sensors move into the shadow of a radio wave from a transponder. Continuous sensing on all sides is needed as the direction to be sensed is not determined.