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Microwave regenerative frequency dividers with low phase noise
1Nat. Inst. of Stand. and Technol., Boulder, CO, USA.
Summary
Researchers developed regenerative divide-by-two circuits achieving low phase modulation (PM) noise. These circuits operate at 18.4 GHz and 39.8 GHz, demonstrating significant noise reduction for high-frequency applications.
Area of Science:
- Electrical Engineering
- Microwave Engineering
- Signal Processing
Background:
- Phase modulation (PM) noise is a critical parameter in high-frequency electronic circuits.
- Regenerative frequency dividers are essential components in various communication and radar systems.
- Minimizing PM noise in frequency dividers is crucial for maintaining signal integrity.
Purpose of the Study:
- To demonstrate novel regenerative divide-by-two circuits with exceptionally low phase modulation noise.
- To evaluate the performance of these circuits at high input frequencies (18.4 GHz and 39.8 GHz).
Main Methods:
- Design and fabrication of regenerative divide-by-two (halver) circuits.
- Measurement of phase modulation noise at specific offset frequencies (10 Hz and 10 MHz).
- Testing at input frequencies of 18.4 GHz and 39.8 GHz.
Main Results:
- The 18.4 GHz to 9.2 GHz divider exhibited PM noise of L(10 Hz)=-134 dBc/Hz and L(10 MHz)=-166 dBc/Hz.
- The 39.8 GHz to 19.9 GHz divider showed PM noise of L(10 Hz)=-122 dBc/Hz and L(10 MHz)=-167 dBc/Hz.
- Achieved very low phase modulation noise levels at both tested frequencies.
Conclusions:
- Regenerative divide-by-two circuits can achieve very low phase modulation noise.
- The demonstrated circuits are suitable for high-frequency applications requiring minimal phase noise.
- These findings contribute to the advancement of low-noise frequency division technologies.
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