Signal Generator Calibration Services for RF & Microwave Applications—A Comprehensive Guide

A high-performance RF/microwave signal generator (Keysight E8257D PSG). Regular calibration ensures this equipment meets its specified accuracy and performance. Signal generator calibration is the process of verifying and adjusting a signal generator’s output to ensure it meets defined accuracy standards. It involves comparing the generator’s output frequency, amplitude, and signal quality against trusted reference standards and making any necessary corrections. For critical industries – from wireless telecommunications to aerospace and defense – regular calibration of RF and microwave signal generators is essential to maintain connectivity, safety, and performancenist.gov. Aumictech specializes in signal generator calibration services, offering NIST-traceable RF calibration procedures that adhere to stringent quality standards to support engineers and technicians worldwide. In this in-depth guide, we explore how calibration works, why it’s crucial in various applications, discuss major generator models (Keysight, Rohde & Schwarz, Anritsu, Tektronix), and outline Aumictech’s ISO/IEC 17025-compliant methods, calibration intervals, and complementary services like repair and refurbished sales.

Understanding the Signal Generator Calibration Process

Signal generators (RF, microwave, or function generators) must produce highly accurate signals in terms of frequency, output power, and waveform purity. Over time, factors like component aging and temperature drift can cause a generator’s output to deviate from its specificationelectronicspecifier.com. Calibration is performed to correct these drifts and document the instrument’s accuracy. The technical calibration process typically includes the following steps and checks:

• Frequency Accuracy Calibration: The signal generator’s output frequency is measured using a high-precision frequency counter or reference receiver locked to a primary standard (such as a GPS-disciplined oscillator or rubidium standard). Any frequency error is adjusted or noted. Because reference oscillators drift over time (aging), frequency calibration on a regular schedule is critical – the longer the time since last calibration, the more the internal reference can driftelectronicspecifier.comelectronicspecifier.com. Frequency accuracy is especially vital in RF applications (e.g. cellular bands or radar frequencies) where an off-frequency signal can cause interference or measurement errors.
• Output Power/Level Calibration: The generator’s amplitude output (in dBm or volts) is tested across its frequency range using calibrated power sensors or thermal power meters. This ensures that when the generator is set to, say, +0.00 dBm, the actual output power is indeed 1 milliwatt (within tolerances). Any deviation is adjusted via internal calibration controls or characterized in a calibration report. Amplitude flatness and linearity across frequencies are verified – for example, a high-quality generator will have very flat output amplitude versus frequencyelectronicspecifier.com. Calibrating output power is crucial for systems in aerospace/defense where precise RF power ensures reliable system performancenist.gov.
• Phase Noise and Spectral Purity Verification: High-end RF and microwave generators are expected to have low phase noise and minimal spurious signals. During calibration, phase noise can be measured using a phase noise analyzer or spectrum analyzer with a reference source. Spurs and harmonic distortion are checked against the manufacturer’s specs. While phase noise generally cannot be “adjusted” in hardware during calibration, measuring it confirms whether the unit meets its spec or if maintenance is needed. This is important because low phase noise is crucial for communications and radar applicationskeysight.com, and spectral purity (lack of spurs/harmonics) prevents interference in adjacent channelselectronicspecifier.com.
• Modulation Fidelity and Functional Tests: If the signal generator supports modulation (AM/FM, pulse, or complex I/Q vector modulation), the calibration process will test these features. For example, a calibrated modulation analyzer or oscilloscope might measure an AM depth or FM deviation to ensure the generator’s modulation settings are accurate. Vector signal generators are often checked for Error Vector Magnitude (EVM) on a known test waveform to verify modulation fidelity is within spec. In high-end applications (telecom standards testing, etc.), modulation accuracy and low EVM are critical performance metrics, so calibration of these functions builds confidence in the generator’s output qualityelectronicspecifier.com.
• General Inspection and Adjustment: Beyond the specific electrical specs, a thorough calibration service will include checking the signal generator’s connectors (e.g. output N-type or SMA connectors for wear or damage), verifying the internal reference oscillator locking and any built-in self-calibration routines, and updating firmware if applicable. Environmental conditions (temperature, humidity) are controlled or noted, since these can affect measurement accuracy. Finally, all results are documented, and a calibration certificate is issued.

Throughout these steps, traceable standards are used – meaning every reference instrument (counters, power meters, etc.) has its own calibration linking back to national standards (NIST or equivalent). This chain of comparisons ensures the measurements are trustworthy and globally recognized.

Importance of Calibration in RF, Microwave, Telecom, Aerospace & Defense

Regular calibration yields multiple benefits: it ensures equipment accuracy, consistency with other instruments, and compliance with industry standardstridentcalibration.com. Different high-tech sectors rely on calibrated signal generators for different reasons:

• Wireless & Telecom: Communications networks operate on tightly controlled frequencies and signal levels. Frequency accuracy is vital to RF applications like cellular or Wi-Fi bands – a small frequency error could push a test signal out of its channel and give misleading resultselectronicspecifier.com. Calibrated signal generators ensure that when you test a receiver or transmitter, the test signals are at the correct frequency and modulation, preventing interference and ensuring devices meet regulatory specs (e.g. 5G NR, LTE, Wi-Fi standards). Power accuracy is equally important for link budget tests; an uncalibrated generator might emit 1 dB low or high, which can mask compliance issues in transmitters or receivers under test.
• Aerospace & Defense: Defense contractors and aerospace companies use RF/microwave signal generators for radar testing, electronic warfare simulations, and satellite communications. In these applications, precise frequency and power control ensures mission reliability and system performancenist.gov. For example, radar target simulators require extremely stable and calibrated signal sources to test radar receivers. In aerospace, an error in signal generator output could translate to faulty readings in navigation or communication system testing. Calibration provides confidence that all test signals are accurate, which is crucial for safety-critical systems. Moreover, many aerospace/defense programs and military standards require traceable calibration records for all test equipment as part of quality and compliance (e.g. MIL-STD calibration programs).
• Research & Development (R&D): Engineers in R&D labs (whether in academia or industry) rely on signal generators to develop and characterise new RF devices, components, or systems. In an R&D setting, accuracy directly impacts the integrity of experiments. A calibrated signal generator allows an RF engineer to trust that an observed effect (say, a filter’s response or an amplifier’s gain) is due to the device-under-test and not an error in the test signal. Additionally, modern R&D often pushes into higher frequencies (mm-wave, 5G, 6G research) and wider bandwidth waveforms. Regular calibration ensures the generator continues to meet its published specs (for example, maintaining <±0.3 dB amplitude accuracy or low distortion), even as it ages. This is important for comparing results over time and between different labs. Ultimately, calibration in R&D prevents lost time chasing measurement errors and provides a solid foundation for innovation.
• Manufacturing & Maintenance: In production test environments (for RF modules, radios, etc.), signal generators are used 24/7 for end-of-line testing and calibration of products. Any drift in the generator could lead to entire batches of products being mis-tuned or failing compliance later. Regular calibration of the production test signal generators ensures consistent manufacturing quality. Similarly, field service technicians and calibration labs in telecom or military maintenance use signal generators for troubleshooting – having those generators calibrated means field measurements (like signal strength, interference tests) are reliable. This reduces the risk of misdiagnosing issues due to faulty test gear. In summary, across applications, calibration ensures an instrument’s readings are consistent with standards (like NIST) and that the instrument remains trustworthy over timetridentcalibration.com.

Major Signal Generator Brands and Notable Models

An example of a programmable RF signal generator (Anritsu MG3642A). Leading brands like Keysight, Rohde & Schwarz, Anritsu, and Tektronix produce signal generators that require regular calibration to maintain their high accuracy. Modern RF and microwave signal generators come from various manufacturers, each with flagship models known for high performance. Aumictech’s technicians are experienced with all major brands. Whether you need Keysight signal generator calibration or service for a less common model, it’s important to understand the capabilities of these instruments and why calibration is critical to uphold them. Below are some notable brands and models:

• Keysight Technologies (Agilent) – PSG Series: Keysight’s PSG series are metrology-grade microwave signal generators. For example, the E8257D PSG analog signal generator delivers industry-leading output power, level accuracy, and phase noise performance up to 67 GHz (operational to 70 GHz with options)sonoransurplus.com. These generators offer extremely low phase noise and high stability sources used in radar and satellite test. Regular calibration of Keysight PSG units ensures their frequency coverage (up to tens of GHz) and output amplitude remain within the tight tolerances required for advanced RF testing. Keysight typically recommends annual calibration for most of its test equipmentdatatec.es, although some newer models may have 2- or 3-year intervals. Aumictech provides full support for Keysight/Agilent models including PSG, MXG, and EXG series – maintaining Keysight signal generator calibration to factory specifications.
• Rohde & Schwarz – SMB100A & SMF100A: Rohde & Schwarz produces a range of high-performance signal generators. The R&S SMB100A is a compact microwave signal generator with frequency options up to 40 GHz, known for outstanding spectral purity (SSB phase noise ~ –128 dBc/Hz at 1 GHz offset) and high output power up to +27 dBmelectrorent.com. Meanwhile, the R&S SMF100A covers 100 kHz to 43.5 GHz with very low phase noise (typ. –120 dBc/Hz at 10 GHz) and up to +25 dBm output powerscdn.rohde-schwarz.com. These specifications are impressive, but only meaningful if the unit is calibrated to verify that the actual performance meets the spec. Rohde & Schwarz often specifies longer calibration intervals (for example, the SMB100A has a recommended calibration interval of up to 3 yearsassets.testequity.com under normal use) thanks to internal self-monitoring and high stability design. Still, many R&S users calibrate annually to ensure critical parameters like phase noise and output linearity haven’t degraded. Aumictech uses specialized procedures for R&S generators, including checking electronic attenuators and leveled output across the wide frequency range.
• Anritsu – MG3690C Series: Anritsu’s MG369xC series are broadband microwave signal generators popular in both commercial and defense labs. The Anritsu MG3694C covers frequencies from audio (0.1 Hz) up to 40 GHz in a single coaxial output, and can be extended to 325 GHz or beyond with external frequency multiplier modulesatecorp.com. This series offers multiple phase noise performance options (Standard, Ultra-low, Premium) to suit different applicationsatecorp.com. With such wide range and configurable performance, calibration is essential to ensure the generator is meeting the selected performance level. For instance, when an MG3694C is set for “Premium Phase Noise” mode, Aumictech’s calibration will verify that the phase noise at key offsets indeed matches the premium spec. Calibration also covers leveling accuracy across the entire 2–40 GHz span and verifies the operation of any options (like the internal IQ upconversion option for vector modulation). Our team is well-versed in Anritsu signal generator maintenance and calibration, supporting models like the MG36xx series and the newer Anritsu “Rubidium” signal generators.
• Tektronix – AFG Series (Arbitrary/Function Generators): Not all signal generators are high-GHz microwave sources; many labs use mid-frequency function generators like Tektronix AFG series for waveform generation up to hundreds of MHz. The Tektronix AFG31000 series for example provides output frequencies from 1 µHz up to 250 MHz with high signal fidelitytek.com. These instruments produce precise low-frequency and baseband waveforms used in electronics testing. Calibration for function generators like the AFG series ensures the output voltage is accurate (for example, a 5.00 Vpp sine wave really is 5.00 Vpp into 50 Ω), and that frequency and waveform shape (sine, square, etc.) are generated correctly without excess distortion. Tektronix typically suggests a 1-year calibration cycle on their equipment to maintain accuracy. Aumictech’s calibration services cover RF equipment calibration from audio-frequency generators up through microwave sources – so function generators (AFGs), pulse generators, and similar equipment get the same rigorous treatment. With proper calibration, even a 100 MHz function generator can be confidently used as a reference in audio and RF labs.

Pro Tip: Regardless of brand, always follow the manufacturer’s recommended calibration interval or sooner if the instrument is heavily used. As Keysight notes, while 12 months is a common interval, many modern instruments can go 24 or 36 monthsdatatec.es – but this should be based on data and usage conditions. Aumictech can help you determine an optimal calibration schedule tailored to your equipment and usage to balance cost and risk.

Aumictech’s Calibration Methods, Standards, and Equipment

Aumictech is committed to delivering traceable, high-quality calibration for every signal generator we service. Our lab’s procedures are ISO/IEC 17025-compliant, meaning they meet the internationally recognized standard for competence of testing and calibration laboratories. We utilize well-documented processes, validated test methods, and measurement uncertainty analysis to ensure confidence in results. Here are some key aspects of our calibration approach:

• NIST-Traceable Standards: All reference instruments and standards used by Aumictech are traceable to the National Institute of Standards and Technology (NIST) or equivalent national metrology institutes. A NIST-traceable calibration certificate confirms that the equipment’s calibration can be linked through an unbroken chain of comparisons back to NIST standardsscalesplus.com. In practice, this means the frequency counters, power meters, attenuators, and oscilloscopes in our lab have their own certified calibrations. The benefit to you is assurance that measurements like “10.000000 GHz” or “0 dBm” are accurate and globally recognized. Traceability is documented in every calibration report we issue, along with before/after data.
• ISO/IEC 17025-Compliant Procedures: While not every calibration provider is an accredited lab, Aumictech follows ISO/IEC 17025:2017 guidelines to drive our quality system. This involves regular internal audits, proficiency testing, and meticulous documentation. An ISO 17025 accredited or compliant lab is periodically audited by an external body to ensure procedures, training, and equipment management meet the stringent requirementsscalesplus.com. For example, our technicians undergo routine training and competency evaluations in RF calibration techniques. We maintain calibration procedure documents for each model or type of instrument, outlining the specific test points and methods to use. Adherence to this standard ensures that our calibrations are not only accurate but also consistent and reproducible. It also means we provide comprehensive certificates with measurement results, uncertainties, and evidence of traceability – important for customers in regulated industries.
• Specialized Calibration Equipment: Calibrating RF and microwave signal generators demands sophisticated test equipment. Aumictech’s lab is equipped with high-precision gear to cover DC to millimeter-wave frequencies. This includes ultra-stable 10 MHz frequency references (disciplined by GPS for long-term accuracy), multi-GHz frequency counters with <±0.1 ppm accuracy, and phase noise measurement systems for analyzing signal purity. We use calibrated RF power sensors and attenuators to measure output levels from –120 dBm up to +30 dBm across frequency bands (for instance, thermistor or diode-based power standards for microwave frequencies). For vector signal generators, we have vector signal analyzers and oscilloscopes to verify modulation performance and waveform shape. We even utilize automated calibration software for certain complex instruments – this software controls the signal generator and reference equipment to step through frequency and amplitude points, logging any adjustment needed. The combination of advanced hardware and software ensures traceable RF calibration with very low uncertainties. In essence, Aumictech’s lab mirrors the capabilities of manufacturer service centers, but with personalized service and faster turnaround times in many cases.
• Comprehensive Calibration Process: When you send your signal generator to Aumictech, our process includes an incoming inspection, full calibration, and, if needed, minor adjustments at no extra charge. If we find the unit out-of-tolerance and it has manual or software-adjustable calibration settings, we perform those adjustments to bring it back within spec. We then verify all results again. If any parameter cannot be adjusted into tolerance due to a hardware issue, our team will consult with you on repair options (see next section). Finally, we provide a detailed calibration certificate. Our certificates typically include: the “as-found” and “as-left” data for critical parameters, measurement uncertainties, the list of reference standards used (with their traceability info), and the next due calibration date. This documentation helps you satisfy any quality management or audit requirements. We maintain electronic records of all calibrations, so if you ever need historical data or have an audit, we can support you.

By combining world-class standards, strict procedures, and top-notch equipment, Aumictech ensures that your calibrated signal generator will perform as expected. Calibration essentially realigns your instrument with reality, and our goal is to make that alignment as precise as possible.

Calibration Intervals and Industry Standards

Determining how often to calibrate your signal generator is an important part of equipment maintenance. Typical calibration intervals for RF test equipment are often annual (12 months), but the optimal interval can depend on the instrument’s stability and how it’s used. Historically, most manufacturers recommended a 1-year interval for calibration. This one-year cycle is still very common todaydatatec.es and aligns with many quality assurance programs (such as ISO 9001 or ANSI/NCSL Z540). Calibrating every 12 months minimizes the risk of excessive drift; as we noted earlier, crystal oscillator aging and component wear will gradually degrade accuracy over timeelectronicspecifier.com. A yearly check catches any significant errors before they impact your work.

However, modern metrology advancements have allowed longer intervals for some equipment. For instance, Keysight has introduced instruments with 2-year or even 3-year recommended intervalsdatatec.es. Rohde & Schwarz’s high-end generators like the SMB100A advertise a 3-year recommended calibration intervalassets.testequity.com under specific operating conditions. These extended intervals are possible due to better internal self-calibration routines and more stable components. It’s important to note that these are guidelines assuming normal use (e.g. instrument used in a stable lab environment, 40 hours/week). If your generator is in continuous use or in a harsher environment (vibration, temperature swings), you might calibrate more frequently. Conversely, if an instrument is rarely used, you might stretch the interval slightly – but we advise not to exceed the manufacturer’s recommendation without a documented stability analysis.

Aumictech can assist in setting appropriate intervals. We generally default to a 12-month cycle for RF generator calibration service, as this offers a good balance of assurance and convenience for most customers. During each calibration, we also look at historical data of the instrument. If we observe that an instrument has had virtually no drift over multiple years, we might suggest extending the interval (with customer approval). On the other hand, if an instrument comes in significantly out-of-tolerance after one year, we might recommend a shorter interval or interim cross-checks. Our goal is to ensure your equipment stays within spec throughout its use.

In terms of standards, Aumictech’s calibration services ensure compliance with relevant industry and regulatory standards. We already operate under ISO/IEC 17025 principles for technical competence. Additionally, our calibration certificates meet the requirements of ANSI/NCSL Z540-1 (a U.S. standard for calibration labs) and ILAC guidelines, which is important for defense and aerospace contractors. If your organization follows MIL-STD calibration programs or requires specific data reporting, we can tailor our service to meet those needs as well.

Recap: Most signal generators should be calibrated at least once a year to maintain accuracy. This interval addresses the typical aging (the “time between calibrations is also known as the aging effect”electronicspecifier.com) and keeps your instrument aligned with standards. With each calibration, you effectively reset the clock on accuracy, minimizing uncertainty in your measurements. Trust Aumictech to help manage your calibration schedule – we’ll send reminders when your equipment is coming due, so you never have uncalibrated gear on the bench.

Beyond Calibration: Repair and Refurbished Equipment Sales

In addition to calibration, Aumictech offers full-service repair and refurbished equipment sales, making us a one-stop solution for test equipment needs. We understand that if a signal generator fails calibration or is not performing correctly, downtime can be costly. That’s why our team includes experienced repair technicians who can troubleshoot and fix issues on a wide range of test equipment.

Repair Services: If during calibration we find a problem – for example, an output attenuator not leveling correctly, or an excessive phase noise due to a failing oscillator – we will alert you immediately. Minor adjustments are often handled as part of the calibration process, but if a major repair is needed, Aumictech can often perform it in-house upon your approval. We stock common replacement parts (connectors, attenuators, oscillator modules, etc.) for major brands. Our Anritsu signal generator maintenance capabilities, for instance, allow us to replace aging internal reference oscillators or repair blown output amps in those units, then calibrate them afterward. We follow manufacturer service manuals and use genuine or high-quality compatible parts to ensure the instrument is restored to like-new performance. Every repaired unit is fully calibrated and tested before return. By combining repair with calibration, we save you time – there’s no need to send the unit to a separate repair center and then to a cal lab; we handle both, reducing overall turnaround.

Refurbished Equipment Sales: Aumictech also provides refurbished test equipment for customers looking to purchase additional signal generators or other instruments at a lower cost. Our inventory of refurbished gear often includes models from Keysight (Agilent), Rohde & Schwarz, Anritsu, Tektronix, and more – all of which have been inspected, repaired if necessary, and calibrated by our team. When you buy a refurbished signal generator from Aumictech, it comes with a current calibration certificate and a warranty for peace of mind. This is an economical way for labs to expand their capabilities or replace obsolete models. For example, if you have an older 2 GHz generator that’s no longer supported, we might offer a refurbished 6 GHz unit as an upgrade. We can also provide trade-in credit for your old equipment. Each refurbished unit goes through the same rigorous calibration and quality checks as customer equipment, ensuring it meets original specifications. We’re proud that many of our refurbished sales go to repeat customers who trust our quality.

Customer Support and Reach: Our services are not limited by geography – we support clients nationally and internationally. Aumictech’s calibration and repair services have served RF engineers and technicians across the United States, and we are capable of handling international calibration requests with proper shipping arrangements. We provide technical support to help with any troubleshooting, even after calibration. If you have questions about using your signal generator, or interpreting calibration data, our knowledgeable staff is here to help. We believe in building long-term partnerships with our clients: keeping your test equipment accurate, extending its lifespan through proper maintenance, and supplying reliable refurbished replacements when needed.

Conclusion

Precision signal generators are the unsung heroes in RF, microwave, and electronics testing – but they are only as good as their last calibration. Inaccurate signals can lead to false conclusions or non-compliant products, which is why professional RF equipment calibration services are invaluable. We’ve explored how calibration works for signal generators, the critical performance metrics it safeguards (frequency accuracy, output level, phase noise, etc.), and why industries from telecom to defense insist on calibrated equipment for their operations. We also reviewed top signal generator models from Keysight, R&S, Anritsu, and Tektronix, illustrating that even the most advanced instruments require periodic verification to stay within spec.

Aumictech is committed to excellence in this field – providing signal generator calibration that is meticulous, traceable RF calibration to NIST standards, and aligned with ISO 17025 best practices. By choosing Aumictech, you ensure your test signals are as accurate and pure as they should be, underpinning the validity of all your testing and development work. Furthermore, with our repair services and refurbished sales, you have a partner to support the entire lifecycle of your test equipment: from purchase to calibration, maintenance, and eventual upgrade.

Don’t leave your critical measurements to chance. Trust Aumictech’s experienced team and comprehensive calibration solutions to keep your signal generators and RF test equipment in peak condition. Whether you’re an RF engineer, aerospace contractor, telecom professional, or lab technician, our services are tailored to meet your exacting demands – locally, nationally, and internationally. Contact Aumictech today to schedule your next signal generator calibration or to inquire about our RF equipment services. With Aumictech, you can be confident that your signals are accurate, your equipment is reliable, and your projects are on course for success.