Frequency Measuring System for THz Sources

The Bridge12 FMS is a precision frequency measurement system to measure and track the output frequency of terahertz (THz) sources, such as traveling wave tubes (TWTs) or gyrotrons. The Bridge12 FMS enables a user to measure the frequency of most THz sources, track a gyrotron’s or TWT’s output frequency throughout the duration of an experiment, or troubleshoot DNP-NMR and other experiments to eliminate frequency issues.
Complete your experiment successfully and on time

Complete your experiment successfully and on time

Whether you’ve built your own THz source or are using a commercial device, gyrotrons and TWTs are sensitive instruments that can change their frequency even due to simple fluctuations of the room temperature. Troubleshooting an experiment can be challenging when you don’t have a way to measure THz radiation.

The Bridge12 FMS helps you eliminate a common source of errors from your experiments so you can complete your measurements successfully and on time.

Focus on your core expertise: Your research

Focus on your core expertise: Your research

As a scientist, you are tempted to build your own instrumentation. The question to ask yourself is whether this is the fastest way to complete your primary goal - your research. Developing a homegrown system can sidetrack you from your main projects and make it difficult to train other team members to run or even maintain equipment. Building a system for the first time may turn out to be more expensive than an off-the-shelf device.

The Bridge12 FMS is a turn-key frequency measurement system enabling you to focus on your actual work. Being well documented and supported, the system can be deployed quickly between experiments to ensured that research isn’t impacted even as specialists leave your group. Bridge12's custom software automates the entire frequency search and completes the process in seconds. The compact hardware replaces a rack full of precision and expensive instrumentation hardware in the laboratory.

A heterodyne receiver with a broad frequency range

The Bridge12 FMS is a heterodyne receiver based on a sub-harmonic mixer that can measure frequencies from about 26 GHz up to 500 GHz, depending on the configuration of the front end.

The system uses a high-precision, internal, tunable LO microwave source. The input signal is down-converted to an intermediate frequency (IF), which is amplified prior to being recorded by the built-in spectrum analyzer.

To determine the unknown frequency of the THz source (RF) the frequency of the local oscillator (LO) is tuned such that the n-th harmonic of the harmonic mixer down-converts the incoming signal to an intermediate frequency (IF) within the IF bandwidth of the Bridge12 FMS. This signal is then measured in real-time using an internal spectrum analyzer.

Simple Control Software for Measuring and Tracking

The Bridge12 FMS comes with simple, user-friendly control software, which is installed on a tablet device, for measuring and tracking frequencies. The software has a simple quick-search function to rapidly measure a frequency. The specific settings and search parameters can be stored in a user profile. That way, a user can define different search ranges and can easily switch between different frequencies.

In addition, the system tracks and logs the measured frequency over time, writing data to internal storage. The system can be configured with a detachable head, mounted to the base unit. The much smaller head can also be connected using a flexible SMA cable to reach remote locations.

Technical Specifications

  • Frequency Range: 26 GHz - 1 THz (standard waveguide bands)
  • Maximum Input Power: + 20 dBm (100 mW), continuous wave
  • Minimum Signal Sensitivity: 0 dBm (1 mW; at 200 GHz)
  • Accuracy: +/- 0.007 * n GHz (n = harmonic number)
  • Typical LO Frequency Range: 8 – 20 GHz
  • System Size (W x H x D): 10.2 x 5.1 x 11.8 (inch), 26 x 13 x 30 (cm)
  • System Weight: 9.4 lbs (4.3 kg)
  • Input Power: 110 - 220 V (50/60 Hz)

Any questions?