Title :
Ultra-Linear Superwideband Chirp Generator using Digital Compensation
Author :
Straayer, Matthew Z. ; Messier, Andrew V. ; Lyons, W. Gregory
Author_Institution :
MIT Lincoln Lab., Lexington, MA
Abstract :
A novel digital compensation technique is applied to linearize the frequency generation of a superwideband chirp. Ultra-linear, low-noise swept local oscillators (SLO) are critical to the two-tone dynamic range performance of compressive receivers. The proposed technique enables full software control of the chirp linearity, slope, and offset to allow automated real-time calibration and testing, including automatic compensation for temperature variation. This approach combines recently available commercial high-speed digital, mixed-signal, and analog integrated circuits along with microwave components to create a 15.5-24 GHz chirp over 60 nsec with <0.4% non-linearity. This technique for high speed chirp generation also has application to FMCW and pulse compression radar systems
Keywords :
chirp modulation; compensation; microwave generation; microwave receivers; voltage-controlled oscillators; 15.5 to 24 GHz; FMCW radar systems; analog integrated circuits; compressive receivers; digital compensation; frequency generation; high speed chirp generation; high-speed digital circuits; low-noise oscillators; microwave components; mixed-signal integrated circuits; pulse compression radar systems; swept local oscillators; ultralinear superwideband chirp generator; Automatic control; Automatic testing; Calibration; Chirp; Circuit testing; Dynamic range; Frequency; Linearity; Local oscillators; Temperature control; Distortion; microwave generation; microwave receivers; nonlinear circuits; nonlinearities;
Conference_Titel :
Microwave Symposium Digest, 2006. IEEE MTT-S International
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-9541-7
Electronic_ISBN :
0149-645X
DOI :
10.1109/MWSYM.2006.249556
