Title :
Phase decrement type direct frequency synthesizer driven by a DDS
Author :
Tajima, K. ; Tsuru, H. ; Ikematsu, H. ; Itoh, K. ; Isota, Y. ; Ishida, O.
Author_Institution :
Mitsubishi Electr. Corp., Kanagawa, Japan
Abstract :
A phase decrement type direct frequency synthesizer with a quadrature mixer driven by a DDS is presented. Phase decrement of a DDS signal can increase the bandwidth of the direct synthesizer. Overflow of a DDS is employed to achieve phase decrement of the signal without adding an extra circuit. A developed 2 GHz-band synthesizer with sub Hz order frequency step achieves 240 MHz bandwidth, frequency switching time of less than 2 /spl mu/s, phase noise of -117 dBc/Hz at 100 kHz offset, and consumption current of 685 mA.
Keywords :
UHF circuits; UHF mixers; direct digital synthesis; 2 GHz; 2 mus; 240 MHz; 685 mA; DDS driven synthesizer; direct frequency synthesizer; phase decrement type; quadrature mixer; Amplitude modulation; Band pass filters; Bandwidth; Circuits; Clocks; Frequency synthesizers; Land mobile radio; Phase noise; Read only memory; Wideband;
Conference_Titel :
Microwave Symposium Digest, 2001 IEEE MTT-S International
Conference_Location :
Phoenix, AZ, USA
Print_ISBN :
0-7803-6538-0
DOI :
10.1109/MWSYM.2001.966992
