Title :
Investigation of a self-calibrating SSB modulator
Author :
Treyer, Daniel Marco ; Bächtold, Werner
Author_Institution :
Dept. of Inf. Technol. & Electr. Eng., Swiss Fed. Inst. of Technol., Zurich, Switzerland
Abstract :
A method to adaptively calibrate a Hartley phasing-type single-sideband (SSB) modulator for obtaining high carrier and image suppressions is presented. The Hartley SSB modulator is extended by control elements to compensate for circuit nonidealities, a monitor circuit to measure the levels of the undesired residual carrier and image tones, and a digital controller. A direct search algorithm adjusts the control elements to maximize modulator performance. The effectiveness of the technique has been studied on an experimental SSB modulator. Carrier and image suppression ratios of 60 dB have been achieved over a carrier range from 1.40 to 2.35 GHz, a bandwidth of 51%.
Keywords :
calibration; modulators; 1.40 to 2.35 GHz; 60 dB; Hartley SSB modulator; carrier suppression; circuit nonideality; digital controller; direct search algorithm; frequency shifter; image suppression; microwave phase shifter; self calibration; single-sideband mixer; single-sideband modulator; Amplitude modulation; Calibration; MMICs; Microwave integrated circuits; Monitoring; Phase modulation; Phase shifters; Radio frequency; Signal processing; Transmitters; Calibration; SSB modulators; carrier suppression; frequency shifters; image suppression; microwave phase shifters; single-sideband (SSB) mixers;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
DOI :
10.1109/TMTT.2005.859876
