Jul 10, 2018

Release of Optical Head for Vector Network Analyzers

Good news for all antenna designers: SPEAG’s Optical Head for Vector Network Analyzers (OH4VNA) – our latest tool – completely eliminates the uncertainty associated with testing electrically small antennas and devices at frequencies between 500 MHz – 6 GHz. Until now, the exact measurement of the performance of the antennas in mobile, body worn, or implanted devices has been a trial and error process complicated by the presence of cables connected to the antenna that change the electrical size of the device and, thus, also the impedance of the antenna to be measured. The new OH4VNA is a cable-free system that replaces the radiofrequency (RF) cable to the antenna port with a non-disturbing fiber-optics system. This is a major breakthrough as this system is transparent to the RF electromagnetic (EM) fields created by the antenna and allows the mobile device to be characterized in a fully isolated manner – i.e., as when operating under real-life conditions.

Building on SPEAG’s proven optical Time-Domain Sensor (TDS) technology, we have developed the system to be a fiber-optics port extension of any standard vector network analyzer. OH4VNA contains minimum (<0.2 cm3) metallic parts, only opto-electronics, wide-band couplers, and RF connectors in the optical head, bringing the fiber-optics directly to the antenna feed port.

We have worked with leading antenna designers around the globe to optimize the OH4VNA to meet our customers’ needs and to enhance not only compatibility, but also durability and usability. By combining the new OH4VNA with the features of SPEAG’s full-wave 3D EM simulation software, SEMCAD X, antenna design validation becomes easier than ever. Both software solutions feature direct comparison of the S-parameters and allow import of simulation data as the target in the OH4VNA control software.

Specifically, OH4VNA offers the following unique features:

  • measurement of the antenna S11 without the disturbance of a connected cable
  • durable miniaturized connectors at the optical head
  • support of various types of 2-port VNAs
  • advanced measurement control and visualization software
  • calibration standards included for lowest uncertainty calibration of the OH4VNA 
  • direct validation of simulation models in the OH4VNA software

For more information or to request a quotation and updates on the delivery schedule, please contact us at

Latest News
Z43 Glowing Night
Sep 21, 2023