Balanced topology to cancel Tx leakage in CW radar

Author

Kim, Jeong-Geun ; Ko, Sangsoo ; Jeon, Sanghoon ; Park, Jae-Woo ; Hong, Songcheol

Author_Institution

Dept. of Electr. Eng., Korea Adv. Inst. of Sci. & Technol., Daejeon, South Korea

Volume

14

Issue

9

fYear

2004

Firstpage

443

Lastpage

445

Abstract

Balanced topology in radar front-end is presented, which can reduce Tx leakage to receiver drastically. The balanced radar front-end which is composed of a differential cross-coupled oscillator, two Lange couplers, and a Wilkinson combiner is implemented using commercially available InGaP/GaAs heterojunction bipolar transistor technology. The tuning range of voltage control oscillator is 320 MHz from 25.307 to 25.627 GHz. The peak output power is 0.8 dBm. Average Tx-to-Rx isolation is about 40.5 dB. Since the isolation of the Lange coupler is 19 dB, the additional cancellation due to balanced topology is expected to be 21.5 dB. The chip size is 1.05 × 1.70 mm².

Keywords

CW radar; bipolar MMIC; network topology; radar receivers; voltage-controlled oscillators; 25.307 to 25.627 GHz; CW radar; InGaP-GaAs; Lange couplers; Tx leakage; Tx-to-Rx isolation; Wilkinson combiner; balanced radar front-end; balanced radar topology; cross-coupled oscillator; differential oscillator; heterojunction bipolar transistor technology; peak output power; receiver; voltage control oscillator; Couplers; Gallium arsenide; Heterojunction bipolar transistors; Isolation technology; Power generation; Radar; Topology; Tuning; Voltage control; Voltage-controlled oscillators; Balanced radar topology; Tx leakage canceller; small radar;

fLanguage

English

Journal_Title

Microwave and Wireless Components Letters, IEEE

Publisher

ieee

ISSN

1531-1309

Type

jour

DOI

10.1109/LMWC.2004.832080

Filename

1324742