VNA Extender Manufacturers : Comparison with Standard VNAs

Published on February 12, 2026

Introduction : Vector Network Analyzer (VNA) frequency extenders are specialized add on modules that significantly expand the operating frequency range of conventional VNAs into millimeter wave and sub terahertz (THz) bands, enabling characterization of next generation RF, semiconductor, and high speed communication components beyond the native bandwidth of standard VNAs.

VNA extenders are critical because standard VNAs usually top out at 50 or 67 GHz. These modules allow engineers to perform S-parameter measurements in the mmWave and sub-THz ranges (up to 330 GHz and beyond). Let us understand benefits of VNAs with extender over standard VNAs.

Why VNA Extenders are Essential for Modern RF Labs

In the traditional RF laboratory, the Vector Network Analyzer (VNA) is the undisputed centerpiece of measurement. However, as the industry charges toward 6G, advanced automotive radar and sub-THz satellite communications, standard VNAs are hitting a barrier due to their limited support for frequency range.

Most high end VNAs top out at 50 GHz, 67 GHz, or occasionally 110 GHz. To measure performance in the 140 GHz to 1.1 THz range, engineers must turn to Frequency Extenders.

Following are the benefits of VNA with extenders over standard ones.

• Standard VNAs rely on coaxial cables to transport signals. At frequencies above 110 GHz, coaxial cables suffer from extreme signal attenuation (loss) and become physically too small to manufacture reliably. VNA extenders solve this by moving the frequency conversion process directly to the Waveguide Interface.
• Standard laboratory hardware cannot generate or analyze these frequencies natively. The Solution: Extender modules use frequency multipliers to “up convert” the base VNA signal to the target millimeter wave (mmWave) band. This allows full two port S-parameter characterization at previously unreachable speeds.
• At sub-THz frequencies, the wavelength is so small that even the slightest mechanical misalignment can ruin a measurement. Traditional threaded connectors are prone to “cross threading” and mechanical wear, which alters the calibration. Modern extenders now utilize contactless interfaces or “screwless” designs.
• Extenders are compact and lightweight. Their small form factor allows them to be integrated into automated test ranges and compact antenna test ranges (CATR), bringing the measurement capability to the probe tip.
• VNA extenders provide a modular upgrade path.

Popular VNA Extender Manufacturers

Eravant (formerly Sage Millimeter Inc.)

The “ACCESS” series of Eravant is highlighted for reducing setup and calibration time using a “Proxi-Flange™” contactless interface.

• Part Numbers : (STO-1520313-C-E2) V-Band (45 to 80 GHz), E-Band, W-Band, F-Band, D-Band and (STO-03203N12-C-E2) G-Band (220 to 330 GHz). These modules feature a “screwless” measurement design that prevents cross-threading and mechanical wear—a major issue at sub-THz frequencies.

Flann Microwave

It is UK-based manufacturer which has 70-year history and is a global authority on waveguide technology.

• Capabilities: They provide waveguide components and calibration kits from 1 GHz to 1.1 THz. The company offers 33 to 330 GHz switches specifically designed for load-pull systems and on-wafer testing.
• Application: Ideal for metrology grade calibration, which is essential for ensuring the accuracy of some of the VNA extenders.

Anritsu Corporation

The company is known for their radar test and signal analysis solutions. The popular product is PhaseLync™ ME786xA which is distributed 2-port VNA (up to 43.5 GHz). Anritsu is a major provider of the base VNA units that drive frequency extenders. Their “VectorStar” platforms are the industry standard for mmWave extension up to 1.1 THz.

Copper Mountain Technologies

CMT is specialized in USB-based VNAs. It offers product with part number SC5065 is a 2-port 6.5 GHz VNA. Their portable architecture is frequently paired with frequency extenders from companies like Eravant to create low-cost, high-frequency benchtop test stations.

Keysight Technologies

The company manufactures T & M equipment used for high-end validation. One such equipment used for load-pull measurement is Keysight DSA90404A Digital Signal Analyzer. Keysight’s PNA-X series is the most common “host” for high-frequency extenders in military and aerospace labs.

Rohde & Schwarz

R&S provides ZC-series millimeter-wave frequency extenders that connect to VNAs like ZNA, ZVA, or ZNB.

Example: R&S Extender Model (R&S ZC110) supports frequency range from 75 GHz to 110 GHz (W-band) with input frequency from 12.5–18.33 GHz.

Many commercial extenders available from various companies are interoperable with R&S VNAs. The manufacturers are OML Inc., SAGE Millimeter / Eravant, Farran Technology, Virginia Diodes (VDI) etc.

Summary

VNA extenders provide cost effective scalability and measurement flexibility compared to purchasing entirely new ultra high frequency VNAs, but they introduce additional system complexity, calibration requirements, and cost. Overall, VNA extenders are a critical enabling technology for advanced RF research, offering a modular and future proof approach to extending measurement capability beyond conventional VNA limits.