Design of low power WPAN (Wireless Personal Area Network) transceiver and mismatch calibration method in direct conversion architecture

Abstract

Recently, low data-rate, low power, and low cost wireless communication with higher density of tiny nodes is emerging for ubiquitous networking. In 2003, IEEE802.15.4 finished the standardization process for distributed sensor network applications such as home automation and industrial control. In this thesis the development of a 2.4GHz CMOS radio transceiver is reported, which is compliant with the preliminary I EEE802.15.4 standard. For extremely low cost, radio system is designed with high level of monolithic integration and then system packaging directly on printed circuit board (PCB) using chip-on-board (COB) technology. And the power consumption is minimized with appropriate architecture and various design techniques. Especially, the linearity/power optimization is more focusing than the sensitivity in ISM band with many interferers. The maximum utilization of modern CMOS digital technology provides programmability, digital trimming capability. This IC is fabricated using 0.18um RF CMOS process and can handle 250kbps data with the power consumption of 21mW and 30mW in receive and transmit mode, respectively. The alternate version of a WPAN transceiver is also designed, which is fully compliant with the final 1EEE802.15.4 standard. The transceiver adopts dual conversion architecture and mismatch calibration algorithm. For this calibration, both RF technique and digital signal processing are used concurrently, which leads to an effective calibration of phase and gain mismatch in a whole transceiver. To remove the phase mismatch, two dimensional search is done considering phase delay difference as well as phase mismatch. The small imbalance can be easily notified by amplification and calibrated using the proposed phase control techniques in a quadrature generator and LO buffers. After phase mismatch calibration, gain mismatch could be simply calibrated through the separate gain control of VGAs in the linear gain region. The transceiver IC compliant with the ...