Title :
GaAs phase noise characteristics in high frequency synthesizer prescalers
Author_Institution :
Motorola Inc., Plantation, FL, USA
Abstract :
The phase noise of GaAs dividers has been suggested to be 20-30 dB worse than for bipolar ECL dividers. The author investigates this suggestion and its implications for microwave frequency synthesizers. The single-sideband phase noise (SSBN) spectral density of a GaAs prescaler using source-coupled FET logic was found to be better (lower) than that of a bipolar diode-load emitter-coupled logic prescaler when measured at 1 GHz and with a divisor (P) value of 128. The amount of phase noise observed at the offset frequency of 25 kHz for the bipolar and GaAs prescalers, together with the measured phase noise reduction due to the divisor P, was -149 and -161 dBc/Hz, respectively. It is concluded that this analysis clearly indicates that the GaAs prescaler has a lower SSBN than the bipolar circuit.<>
Keywords :
III-V semiconductors; dividing circuits; electron device noise; field effect integrated circuits; frequency synthesizers; gallium arsenide; integrated logic circuits; scaling circuits; 1 GHz; GaAs dividers; III-V semiconductors; digital IC; high frequency; microwave frequency synthesizers; phase noise characteristics; single-sideband phase noise; source-coupled FET logic; spectral density; synthesizer prescalers; Density measurement; Diodes; Frequency synthesizers; Gallium arsenide; Logic; Microwave FETs; Microwave frequencies; Noise measurement; Phase measurement; Phase noise;
Conference_Titel :
Gallium Arsenide Integrated Circuit (GaAs IC) Symposium, 1988. Technical Digest 1988., 10th Annual IEEE
Conference_Location :
Nashville, Tennessee, USA
DOI :
10.1109/GAAS.1988.11077
