design of a stable dielectric resonator oscillator inż. andrzej stefański mgr. inż. krzysztof...
TRANSCRIPT
Design of a stable dielectric resonator oscillator
inż. Andrzej Stefański mgr. inż. Krzysztof Czuba
dr inż. Krzysztof Antoszkiewicz
Instytut Systemów Elektronicznych PW
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 2
Outline
• Objective and specifications
• Dielectric resonator
• Problems to solve
• Current project status
• Future plans
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 3
Objective• Low phase noise Dielectric Resonator
Oscilator (DRO) is needed for the phase reference system for the UVFEL/XFEL projects
• DRO will be synchronized with the Master Oscillator
• DR based oscillators offer very high noise performance but generator design is very difficult
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 4
Specifications
• Output freq. : 1299.9996 MHz
• Voltage controlled input
• Output power : 10 dBm
• Harmonics : < -25 dBc
• Sub-harmonics: < -60 dBc
• Spurious : < -80 dBc
• Extremely low phase noise – next page
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 5
-180
-160
-140
-120
-100
-80
-60
-40
-20
0
Distance from carrier frequency [Hz]
Ph
ase
no
ise
[dB
c/H
z]
Limit -60 -80 -105 -135 -155 -150
10 100 1k 10k 100k 1M
Required phase noise level
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 6
Dielectric Resonator
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 7
Design issues/problems
• Selection of low-noise transistor• Oscillator circuit design• Tuning method selection• Minimizing noise from tuning circuit• Selection of DR coupling method – oscillation and
output signal• Mechanical design: oscillator cavity, DR fixture –
significantly affect oscillator performance
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 8
Recent development
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 9
Current project status
• Analysis of existing design, found ways for oscillator improvement
• 3D electromagnetic field simulations in progress. Objective – find optimum coupling method, estimate quality factor and extract S-parameters for electronic circuit simulations
• 3D model created and first simulation results obtained
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 10
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 11
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 12
Design of a stable dielectric resonator oscillatorA. Stefański, ISE, PW 13
Future plans
• Cavity optimization– 3D simulations– S-parameters extraction
• Circuit optimization– Find transistor with best noise performance– Apply it to optimal circuit
• Make project and build model• Measurements
Thank you