Who We Are

MissionVision

To honor God by prospering ouremployees and serving ourcustomers through theadvancement of mm-wave
component technology

To create superior componentsthat enable the commercializationof technology in the mm-wavespectrum

What We Do
 Micro Harmonics specializes in the design and manufacture of advanced
ferrite components such as Faraday rotation isolators
 Voltage variable attenuators
 Hybrid circulators
 Orthomode transducers
 Cryogenic isolators

 Our products cover every standard waveguide band from WR-28 (26-40 GHz)
through WR-2.8 (260-400 GHz).

About Us
 2008 Founded by Dr. David Porterfield 2008-2015 Company operated as mm-wave design consultancy
 2015-2018 Developed mm-wave ferrite isolators and Y-junction circulators
 2018 First ferrite components released for sale
 2019-2021 Developed cryogenic isolators and voltage variable attenuators

 2021-2023 Developed patented hybrid circulators
 2018-present Global distribution and sales of mm-wave products.

2023 Metrics
Revenue

Growth

Employees$2 million

25%

10

Distinctives

What Sets Us Apart
Lowestinsertion
loss

Highestpowerrating
RF test datafor everyunitOur Guarantee: No two mm-wave components
have the same exact frequency response.
Unique signatures arise from small misalignments
and variations in the internal parts. The
differences can be substantial. Max, Min, andtypical specs are helpful, but what you need tosee are the actual test data for thecomponents you are buying. Micro Harmonics
tests every component across the fullwaveguide band on a vector network analyzer.
We supply the test data to the customer at noadditional cost. Don’t settle for anything less.

Isolators – Overview
 WR-28 thru WR-2.8; 25 GHz to 400 GHz
 Anti-cocking waveguide flanges
 Comprehensive test data
 Lowest insertion loss High isolation
 Compact size
 Diamond heatsinks

 Resist stray magnetic fields
 Internal waveguide screw accessIsolators – Lowest Insertion Loss

Isolators: PerformanceIsolators – Highest Power HandlingRF signals travelling in the reverse direction are absorbed in the isolator and converted toheat energy. Our isolators employ a unique diamond disc that disburses the heat andlowers the operating temperature. The graph shows the maximum reverse power ratingsof our isolators (MHC) and the average of other vendors. The MHC power ratings areconservative to ensure low temperatures and long life.

Isolator Reverse Power Rating

6

Micro Harmonics

Other Vendors

Power (W)

54
32
1
0

WR-28

WR-22

WR-19

WR-15

WR-12

WR-10

WR-8

WR-6.5 WR-5.1 WR-4.3 WR-3.4 WR-2.8

Voltage Variable Attenuators – Overview
 WR-10, WR-6.5; 75 GHz to 170 GHz
 Anti-cocking waveguide flanges

 Comprehensive test data High dynamic range
 Low insertion loss Compact size Low VSWR

Voltage Variable Attenuators: Performance
09.54 V54.20 V

102.37 V

Attenuation [dB]

151.37 V

200.87 V

250.58 V

30

0.42 V

35400.33 V

450.28 V110

120

130140150

Frequency (GHz)

160170

VA65-42Voltage Variable Attenuators: Comparison
 The two primary technologies used for electronically tunable attenuation in the mm-wave are PIN diode androtary vane. A variable bias voltage applied to PIN diodes creates a variable loss mechanism. Rotary vane attenuators
employ a motor driven mechanical actuator to introduce a resistive vane into a waveguide.
 Micro Harmonics Corporation (MHC) is developing a third technology that uses a Faraday rotator to rotate the RF
signal into a fixed resistive layer. This is like a rotary vane attenuator but without the mechanical motion of the vane.
 MHC attenuators are passive and insensitive to ESD damage. The flat response and high dynamic range are muchbetter than the PIN attenuators. The MHC attenuators can be scaled to at least 330 GHz. The power ratings of MHC
attenuators are much higher than PIN devices. Port reflections in the MHC attenuators are significantly lower thanthose in the PIN devices. The insertion loss of the MHC attenuator is lower than the rotary vane or PIN attenuators.
And finally, the MHC attenuators do not generate any measurable noise or harmonic content.
Comparison of PIN Diode Attenuators and MHC Ferrite Attenuators.
Band

WR-3.4WR-4.3WR-5.1WR-6.5
WR-8
WR-10

Frequency Range (GHz)
PINFerriteNA
220-330NA
170-260
NA140-220
110-145
110-170
90-14090-14075-11075-110NA = Not Available.

Insertion Loss (dB)PIN
Ferrite
2.7
2.5
2.3
5
2.04
1.8
4
1.5

Return Loss (dB)PIN
Ferrite171717617617617

Max Power (W)PIN
Ferrite0.4
0.7
1.00.006
1.5
0.006
1.8
0.100
2.3

Hybrid Circulators – Overview
 WR-15 thru WR-3.4; 54 GHz to 330 GHz
 Wideband (24% fractional bandwidth) Internal waveguide screw access Anti-cocking waveguide flanges
 Resists stray magnetic fields
 Comprehensive test data
 Low insertion loss PatentedHybrid Circulators – Bandwidth The Y-junction circulator has been thedominant technology at highfrequencies for many decades.
However, Y-junction circulators arevery difficult to tune at the higher
mm-wave frequencies because thefractional bandwidth is small, and thecenter frequency is highly sensitive tothe ferrite core dimensions.

 The hybrid circulator has significantly
greater bandwidth and higher
frequency coverage than the
traditional Y-junction. It comprises a
Faraday rotator and an orthomodetransducer which work together toachieve the circulator function withan astounding 24% fractionalbandwidth and no bandwidthdegradation at higher frequencies.

Hybrid Circulators – Comparison
 The top figure is an example of atransmit-receive system using a Yjunction circulator. Isolators areplaced on both the transmitter andthe receiver ports to reduce thesignal power reflected to thetransmitter. In a Y-junction circulator,
signals reflected at the receiver arecoupled to the transmitter port which
is why a receiver port isolator issometimes required.
 The hybrid circulator is configured bydefault so that the transmitter port isinternally isolated from the receiver
port. This asymmetry can save space,simplify the system architecture, andimprove the noise figure andsensitivity of the receiver as illustrated
by the figure on the bottom.

Hybrid Circulators: Frequency Coverage

Model NameEIA Flange

Band

HC148
HC122
HC100
HC080
HC065
HC051
HC043
HC034

WR-15
WR-12
WR-10
WR-8
WR-6.5WR-5.1WR-4.3WR-3.4VEW
FDGY
J

Frequency(GHz)
54 – 68
70 – 88
84 – 104
107 – 133
118 – 150
150 – 190
196 – 250
258 – 330

Hybrid Circulators – Fullband

50

20 dB Fractional Bandwidths of mm-Wave Circulators

40Bandwidth (%)

 The asymmetricorthomode transducer inthe hybrid circulator
currently achieves a 24%
fractional bandwidth.
Micro Harmonics’ isdeveloping an orthomodetransducer using asymmetric design which
will achieve 40% fractional
bandwidth. This new
design in conjunction with
our full band Faraday
rotator will enable themanufacturing of fullband hybrid circulators

3020
100
WR-15 WR-12 WR-10 WR-8 WR-6.5 WR-5.1 WR-4.3 WR-3.4

Y-junction

Hybrid (24%)

Hybrid (fullband)Hybrid Circulators: PerformanceOrthomode Transducer – Overview
 WR-6.5; 110 GHz to 170 GHz
 Low cross-polarization coupling Anti-cocking waveguide flanges
 Resists stray magnetic fields
 Comprehensive test data
 Low insertion loss Compact size

 High isolation

Orthomode Transducer: Performance

Cryogenic Isolators: Overview
 WR-28 thru WR-5.1; 26.5 GHz to 220 GHz
 Anti-cocking waveguide flanges

 Comprehensive test data
 Lowest insertion loss High isolation
 Compact size

 Optimized for 1 – 100K
 Resist stray magnetic fields
 Internal waveguide screw accessCryogenic Isolators: Performance

Cryogenic Isolators: Why?
 It is a common misconception that isolators designed to work at room
temperature will work reasonably well at cryogenic temperatures. The
problem is that the ferrite materials have a strong temperaturedependence that impacts the signal rotation. This can severely degrade
performance at cryogenic temperatures.
 Our cryogenic isolators are routinely tested at 25 K in our cryostat. We use a
resistive thin film for isolation that is not in the class of super conductors. The
performance of our cryogenic isolators has been verified down to 1 K.
 MHC cryogenic isolators are designed to withstand the thermal stresses thatare inherent in cryogenic systems.

Applications
 Atmospheric observation
 Biomedical Portal security
 Radio astronomy
 Research lab
 Remote sensing Standoff detection
 Telecommunication
 Test and measurement equipment
 University

Links Why are our distinctives important?
 Informational resources Blog Hybrid Circulator
 Variable Attenuator FAQ (coming soon) Our Videos

Company Info
20 S Roanoke St, Ste 202

Socio-Economic Category: SBFincastle, VA 24090

DUNS: 034119968

Phone: 540.473.9983
Toll Free: 833.473.9983 (US only)
Email: Sales@mhc1.com

Cage Code: 6T4C6HS Code: 8536 3010 90
NAICS: 334220, 334419, 541330, 541715

MHC Distributors

PSC:

H259, AJ12, 5985, 5999
C219, AR12, C222, C215