RF & MICROWAVE PROCUREMENT ENGINEERING NOTE
HOW TO WRITE AN
RF & MICROWAVE
RFQ
A strong RFQ gives engineering enough information to identify, manufacture, modify or source the correct RF component without forcing the supplier to guess what matters. Start with the complete frequency requirement, then define the electrical, mechanical, environmental, quantity and delivery constraints that actually determine the part.
THE MINIMUM USEFUL REQUIREMENT
START WITH THE
DECISION-MAKING DATA.
The strongest RFQs separate required values from preferences. If a specification is mandatory, state the limit. If it is flexible, state the preferred value and acceptable range. This gives engineering room to identify an existing model or propose a practical modification without weakening the real requirement.
Name the RF function
Specify what the signal path must do: shift phase, attenuate level, transition waveguide to coax, radiate, isolate, divide, combine, filter or amplify.
Give the complete band
Center frequency alone is usually not enough. State minimum and maximum operating frequency so broadband performance can be reviewed correctly.
State the number that defines the part
Examples include 90° phase shift, 30 dB attenuation, 15 dB antenna gain, 20 dB isolation or a required cutoff/passband.
Define what cannot be exceeded
Include insertion loss, VSWR/return loss, power, flatness, accuracy, ripple, directivity, phase error or other model-specific limits.
Electrical and mechanical fit matter
State SMA, Type N, 2.92 mm, 3.5 mm, waveguide size, flange, sex, orientation and mounting requirements where relevant.
Explain the signal path
A short application description helps engineering distinguish between a test-lab requirement, production subsystem, airborne assembly, ground station or other operating environment.
The current Impulse requirement form collects component type, frequency range, waveguide size, connector, manufacturer, existing part number, primary specification, secondary specification, quantity, drawing/datasheet and application information before matching or escalation.
INTERACTIVE RFQ BUILDER
TURN THE REQUIREMENT
INTO A CLEAN RFQ.
Fill in what you know. The builder scores technical completeness and generates a copyable RFQ summary. Unknown fields can remain blank; the goal is to distinguish known requirements from unresolved engineering questions.
Complete the fields above to generate the RFQ summary.
Do not place classified, export-controlled or otherwise restricted technical data into an unapproved public form. Use the organization's approved secure channel when the requirement contains controlled information.
ELECTRICAL REQUIREMENTS
SPECIFY WHAT THE RF
PATH MUST PRESERVE.
Every RF component family has a different primary specification, but the supporting limits often decide whether a candidate is actually usable. State performance over the complete operating band and under the power and environmental conditions that matter.
Minimum / maximum / sub-bands
State continuous coverage or identify separate operating channels. If only certain spot frequencies matter, list them explicitly.
FOUNDATIONALVSWR or return loss
Use a clear limit such as VSWR ≤1.50:1 or return loss ≥14 dB over the required band rather than saying “good match.”
MEASURABLEMaximum loss over frequency
State whether the requirement is typical, maximum or acceptance-test limited, and whether cables/adapters are included in the measurement plane.
REFERENCE PLANE MATTERSCW / average / peak / pulse
Power should include duty cycle, pulse width and peak level where relevant. “100 W” is ambiguous when the waveform is unknown.
THERMAL + PEAK STRESSPhase / attenuation / gain / isolation
State nominal value, tuning range, accuracy, step size, flatness or repeatability as appropriate to the component.
PART-DEFINING SPECS-parameters / plots / acceptance data
Define what data is required with the quote, with first article, or with each production unit.
PROCUREMENT OUTPUTMECHANICAL + ENVIRONMENTAL REQUIREMENTS
THE RIGHT RF PART
STILL HAS TO FIT.
Mechanical conflicts are one of the easiest ways to lose time after the electrical match has already been found. Include interface geometry, envelope, mounting and environmental constraints early enough to influence the selected model.
Type, sex and orientation
“SMA” is incomplete when SMA-F, SMA-M, right-angle orientation or panel geometry matters to the assembly.
WR size and flange
Specify both waveguide band and flange where the mating interface is fixed. Add orientation requirements for right-angle transitions.
Maximum size / keep-out zones
Attach a drawing if the component must fit inside an existing chassis, fixture, rack, antenna assembly or test setup.
Hole pattern / tripod / panel / bracket
State whether an existing bolt pattern or mechanical datum must be preserved.
Operating and storage range
If performance limits apply across temperature, state whether the RF specifications are room-temperature only or environmental limits.
Lab, outdoor, airborne, space, military
State only requirements that are actually applicable, including vibration, shock, humidity, sealing, materials, outgassing or screening when relevant.
A partial specification can still be useful if the reference document is attached.
Impulse's current RF Part Finder accepts a drawing or datasheet along with the technical requirement. If an existing or obsolete part must be replaced, the original drawing can expose dimensions, interface details and tolerances that are not obvious from a short model number.
COMMERCIAL + DELIVERY REQUIREMENTS
AN RFQ IS NOT COMPLETE
WITHOUT QUANTITY.
Quantity, delivery timing and documentation affect both technical and commercial feasibility. A one-piece engineering prototype can follow a different path from a repeat production requirement even when the RF specifications are identical.
Prototype versus production
State the immediate quantity and, if useful, expected follow-on volume. This helps distinguish one-time engineering from production planning.
Need-by date or acceptable lead time
Use an actual required date where possible. “ASAP” does not communicate when a schedule becomes unacceptable.
Prototype / qualification split
If a first article, engineering unit or qualification unit is required before production, identify that separately.
Drawing, CoC, test report, S-parameters
State documentation deliverables in the RFQ so they are included in scope rather than added after order placement.
Lot / serial / material requirements
If traceability is contractually required, define it before quotation so manufacturing and inspection planning can support it.
Tell the supplier what can move
Mark acceptable alternatives for connector, flange, envelope, performance tolerance or delivery if flexibility exists.
BEFORE / AFTER EXAMPLES
MAKE THE REQUEST
ENGINEERABLE.
The examples below show how a vague request becomes a technical requirement that can be matched against an existing catalog, quoted as a modification or routed for alternate-part review.
“Need a phase shifter around X-band.”
frequency limits unknown
?phase range unknown
?power unknown
?connector unknown
?quantity unknown
“RF phase shifter for 8.0–12.0 GHz.”
- Required phase range: 90° minimum
- Insertion loss: ≤1.5 dB preferred
- VSWR: ≤1.5:1
- Power: 10 W CW minimum
- Connectors: SMA-F
- Manual adjustment acceptable
- Quantity: 4 prototype units
- Need-by: 8 weeks ARO preferred
- Provide datasheet and test data with quote
“Need a WR90 adapter.”
coax connector unknown
?flange unknown
?orientation unknown
?power unknown
?performance limit unknown
“WR90 to SMA-F adapter for 8.2–12.4 GHz.”
- Waveguide: WR90
- Flange: Cover
- Coax interface: SMA-F
- Orientation: right-angle preferred
- VSWR: ≤1.20:1 preferred
- Power: 25 W CW minimum
- Quantity: 10
- Outline drawing required with quote
RFQ RELEASE CHECKLIST
CHECK THE REQUIREMENT
BEFORE YOU SEND IT.
Not every RFQ needs every field. The objective is to include every specification that can change the selected part, the quoted price, manufacturing method, test plan or delivery schedule.
The RF function is clearly identified.
Minimum and maximum operating frequencies are stated.
Phase, attenuation, gain, isolation or other part-defining requirement is stated.
Insertion loss, VSWR, flatness, accuracy or other limits are included where relevant.
CW, average, peak and pulse conditions are defined when power matters.
Connector, waveguide, flange, orientation and impedance are known or marked flexible.
Drawings, mounting or size limits are attached if fit is constrained.
Operating temperature and environmental requirements are stated if applicable.
Prototype and production quantities are separated if needed.
Need-by date or acceptable lead time is included.
Datasheet, drawing, CoC, test report or S-parameters are identified.
A short description explains the RF signal path and what is mandatory versus preferred.
HAVE THE SPECS?
LET IMPULSE MATCH THE PART.
IMPULSE IN-HOUSE RF HARDWARE
START WITH THE
PRODUCT FAMILY.
Impulse's current in-house product architecture is organized by the job the RF path performs. Use the relevant family page to check standard coverage, then send the unresolved requirement for manufacturing, sourcing or alternate-part review.
RF Phase Shifters
30° / 60° / 90° / 180° · THROUGH 40 GHzUseful RFQ fields: frequency range, phase range, insertion loss, VSWR, power, connector and adjustment/readout style.
VIEW PHASE SHIFTERS → SET THE LEVELVariable Attenuators
CONTINUOUS CONTROL · UP TO 60 dBUseful RFQ fields: frequency, attenuation range, insertion loss, flatness, power, VSWR and connector.
VIEW ATTENUATORS → RADIATE / MEASUREStandard Gain Horn Antennas
1.12–40 GHz · WR650–WR28 · 10 / 15 / 20 dBUseful RFQ fields: frequency/WR band, gain, beamwidth, flange, polarization, mounting and test geometry.
VIEW GAIN HORNS → CHANGE THE INTERFACEWaveguide-to-Coax Adapters
STANDARD WR BANDS · COAXIAL OUTPUTSUseful RFQ fields: WR size, full frequency band, flange, coax connector, orientation, VSWR and power.
VIEW WG-COAX →CURRENT IMPULSE REQUIREMENT PATH
FROM SPECIFICATION
TO QUOTE.
The current Impulse RF Part Finder checks the live catalog first and preserves unresolved technical requirements for manufacturing, sourcing or alternate-part review.
Enter the technical requirement
Component type, frequency, waveguide, connector, manufacturer, existing model, primary/secondary specifications, quantity, drawing and application information.
OPEN RF PART FINDER → IMPULSE IN-HOUSE CATALOGCheck standard product coverage
Browse current Impulse in-house phase control, attenuation, standard gain horn, waveguide-to-coax and RF protection product families.
OPEN PRODUCT CATALOG → IMPULSE SALESSend an RF or microwave requirement
Use the requirement summary, drawing, datasheet or existing model number to begin technical and commercial review.
CONTACT IMPULSE →ENGINEERING + PROCUREMENT FAQ
RFQ QUESTIONS.
These answers address the most common gaps that slow down RF and microwave component quotation.
What information should an RF or microwave RFQ include?+
At minimum, identify the component type, complete frequency range, primary electrical specification, interface, quantity and required timing. Add insertion loss, VSWR, power, mechanical, environmental and documentation requirements when they can change the selected part or test plan.
Is a center frequency enough for an RFQ?+
Usually not. Many RF components have frequency-dependent insertion loss, match, phase, attenuation, gain or power performance. State the full required operating range or the exact spot frequencies that matter.
How should RF power be specified?+
State whether the requirement is CW, average, peak or pulsed. For pulsed signals include peak power, duty cycle and pulse width when relevant so thermal and peak-stress limits can be evaluated correctly.
Should I specify VSWR or return loss?+
Either can be used if the limit is unambiguous and measured at the correct reference plane. For example, state VSWR ≤1.5:1 or return loss ≥14 dB across the required band.
What if I only have an old part number, datasheet or drawing?+
Send it. An existing model number, datasheet or mechanical drawing can provide enough information to begin alternate-part, sourcing or custom-manufacturing review even when the new RF specification is not yet complete.
Why does quantity matter before the quote?+
Quantity affects manufacturing setup, component sourcing, inspection, documentation and delivery planning. Separate immediate prototype quantity from expected production volume when both matter.
What should be marked mandatory versus preferred?+
Anything that determines system compatibility, acceptance or safety should be clearly mandatory. Preferred values can be identified separately so engineering can propose practical alternates without violating the true requirement.
