Microwave and RF Components

Selection guides for the component families that make up a microwave signal chain, organised by what each part does and how it is specified.

Component types by signal-chain function

Family	Job and position	Start the specification with
Frequency sources	Provide an LO or excitation signal on a branch feeding conversion	Tuning coverage and phase noise; YIG oscillators
Synthesizers	Make a reference-related programmable source	Step size, spurs, settling and reference; synthesizer guide
Mixing and conversion	Translate the signal band using an LO	Frequency plan, conversion loss, drive and input third-order intercept (IIP3); frequency converters
Filtering and preselection	Pass the wanted region and attenuate unwanted frequencies; placement depends on the frequency plan	Bandwidth, rejection and loss; YIG filters
Amplification	Supply signal gain; position determines its contribution to noise and overload	Gain, noise figure, linearity, output level and bias
Control and passive interconnection	Switch routes, set attenuation, join transmission paths or sample a signal with a coupler	Isolation, loss, matching, power handling and defined port interfaces

Use YIG oscillators for a broad-tuning source candidate, YIG filters for tracking preselection, and synthesizers for reference-related programmable sources. Specify YIG assemblies with their drivers. Converter frequency-plan questions are covered in RF, IF and LO and upconverter versus downconverter.

Begin with the job the block must perform. The functions below follow Michael Steer’s open engineering textbook sections on receiver/transmitter architectures, terminations and attenuators, and waveguide components. The grouping is functional: a passive switch, for example, belongs to control as well as to passive hardware.

Allocate requirements before choosing individual parts

Use the site’s RF signal-chain framework as a set of connected decisions, not a universal series connection. The LO feeds the mixer separately; a receiver can need filtering both before and after conversion, and amplification placement changes the noise and overload trade-off. Steer’s receiver examples show those arrangements.

An effective review sequence is to state the required output/detection conditions, draw the wanted and unwanted frequency paths, and then record the permitted level, noise and distortion at each interface. Work through source, synthesis, conversion, filtering, amplification and the receive/transmit endpoint. Check the complete cascade again whenever a gain, loss or ordering decision changes. This is a planning checklist, not a numerical system allocation or an assurance that independently acceptable parts will form an acceptable receiver.

Use the linked guides for the deeper parameter definitions. For comparing two vendors’ conditions rather than changing the frequency plan, continue to the engineering datasheet checklist.

When a component review also includes industrial power hardware, use the Han 4, Han 4A and Han Q 4/2 naming guide to separate housing-size terms from insert and contact designations before completing the parts list.