Post on 30-Dec-2015
transcript
Grant Hodgson
G8UBN
New Microwave Transverter Concepts
Grant Hodgson G8UBN
New Microwave Transverter Concepts
Topics presented :-
Current Transverter Design
New conecpts with new components
Local Oscillator options
New Microwave Transverter ConceptsConventional 10GHz transverter
5W @ 10GHz based on DB6NT modules
G3PHO
New Microwave Transverter ConceptsConventional transmit converter
ImageFilterMixer
Power Amplifier
2.4GHz LO
Multiplierx4
Attenuator
144MHz3W
10GHz1WHarmonic filter
Driver
New Microwave Transverter ConceptsThe future of Transverters?
•Highly Integrated Cicuit
•All functions ‘on-chip’
•Includes :-•Mixer•Synthesiser•(PLL, VCO)•Driver/PA•LNA•T/R switching
New Microwave Transverter ConceptsThe future of Transverters?
•UNLIKELY -
•Amateur market is too small•Difficult to customise
New Microwave Transverter Concepts
24GHz Waveguide Filter
Photo courtesy of Howard, G6LVB
New Microwave Transverter Concepts
N e w 2 4 G H z D o w n c o n v e rte rL N A(O p tio n a l) S u rfa c e M o u n t
S u b -h a rm o n ic M ix e r
2 .4 G H z L o c a l O sc illa to r
2 4 .0 4 8 G H z
9 6 7 7 .2 M H z
2 4 1 9 .3 M H z
1 4 5 M H z
x2
x2
4 8 3 8 .6 M H z
4 6 9 3 .6 M H z
4 8 3 8 .6 M H z
5 G H z 2 -w ayS p litte r
F ilte r
2 n d M ix e r(d o u b le b a lan c ed )
L S B
9 6 7 7 .2 M H z x 2 = 1 9 3 5 4 .4 M H z
1 st IF am p
New Microwave Transverter ConceptsPerformance of HMC264 sub-harmonic mixer
New Microwave Transverter ConceptsNo-tune 24GHz transverter - Advantages
•Elimination of tunable filters - i.e. •No-tune design•Lower cost•Allows for operation at 24048 or 24192MHz
•Allows operation at 28GHz!
New Microwave Transverter ConceptsNew transmit converter 5.7GHz or 10GHz
Image-rejectMixer
Power Amplifier
2.4GHz LO
Active Quadruplerx4
Attenuator
144MHz3W
10GHz2W
Gain stage
90 degreephase shifter
LO Buffer
New Microwave Transverter Concepts90 degree phase shift network
New Microwave Transverter ConceptsHMC520 transmit converter - measured performance
LO rejection 39dBImage rejection 42dBOther products >37dBAchieved withno filtering!
New Microwave Transverter ConceptsHMC443 Active Quadrupler - measured performance
Fundamental -45dB2nd Harmonic -25dB3rd Harmonic -47dB5th Harmonic -46dB6th Harmonic -35dBAchieved with no filtering!
New Microwave Transverter ConceptsNew transmit converter - Advantages
•Elimination of tunable filters - i.e. •No-tune design•Lower cost•Allows for operation in other parts of the bands•eg. 10450MHz•Or even non-amateur bands such as 8.42GHz (Deep Space)•Allows flexibility in choice of type of LO (PLL, Xtal, DDS etc)•Choice of IF frequencies - 28, 144, 432MHz•High output power - 2W@10GHz•Possibility of Dual-band transverter
New Microwave Transverter ConceptsNew transmit converter - Drawbacks
•Output is not quite as ‘clean’ as fully filtered design•LO drive level is very high (+13dBm @ 10.224GHz)•DC current consumption may be higher•Close-tolerance capacitors required for phase shift network
New Microwave Transverter ConceptsOptions for Local Oscillators
•Crystal Oscillator - can be ovenised or Reflocked•Good (best?) phase noise
•DDS - any frequency you like•Can use OCXO or other hi-stab reference, inc. GPS
•Phase Locked Loop - operating at 2.4GHz, •good phase noise IS possible with careful design•Can use OCXO or other hi-stab reference, inc. GPS•Other novel applications - eg. •120GHz Tx/Rx with single 2.4GHz LO
New Microwave Transverter ConceptsOther no-tune options
•Active bias circuits allow -ve voltages to be set automatically
New Microwave Transverter Concepts
•New components, particularly MMICs, allow new concepts •to be implemented
•No-tune designs are possible
Summary
New Microwave Transverter ConceptsNo-tune transverters are possible - will the next generation see the end of the trim tool?