RF Circuits and Antenna Design with Low Interference in Hospital (III)

Based on the previous design and measurement results of our fabricated RF-transceiver modules as well as published papers in the area of RF circuits, we will investigate on the RF module design for biomedical applications. In addition to lightly weight, small volume, and saving power, some special requirements such as low electromagnetic interference, high susceptibility, long duration, high reliability and flexible versatility are considered for bio-medical applications. Firstly, according to the requirements as mentioned above, we have fabricated the bio-medical RF modules. Moreover, Considerations on the flexible versatility and high reliability for frequency synthesizer are developed in relation to frequency hopping and GMSK modulation. In addition, low-noise amplifier and mixer are high-reliable mixer are fabricated and measured to develop design guidelines. In the second year, aims on the transceiver as integration of RF modules with baseband circuits as developed in the previous year are studied. Special considerations on the sub-project module, substrate noise, electromagnetic radiation and susceptibility, as well as the interface matching-circuits between front-end RF circuit and baseband circuits are of importance. The amplifier operates at 2.4 GHz and having a high power gain, with lower NF in simulation. A CMOS RF mixer with the combination of the CMOS Gilbert Cell mixer and the low voltage design technique of LC tanks is described in this design. The main purpose of proposed mixer is to demonstrate the potential of low voltage applications with higher conversion gain. The frequency divider is a dual modulus phase-switching prescaler. The loop filter is a third-order low pass filter. We have investigated a switching class E approach, which can achieve higher efficiency than traditional classification of power amplifiers. A fully differential topology and the composite switch technique are presented to alleviate the problems of CMOS and to reduce the EM interference of transceivers. Some considerations are studied such as data from ARM bus to be modulated from baseband circuits and radiated through RF front-end modules. Therefore, practical integration of RF front-end modules and baseband circuits to be the embedded SoC modules for bio-medical diagnosis is investigated in this project. To reduce EMI, substrate noise, noise figure, phase noise, and clock delay as well as to consider power management, thermal distribution, and vibration reliability, it is necessary to implement good placement and routing among modules, control lines and signal buses.

Project ID:PB9308-5076
External Project ID:NSC93-2220-E182-004