Mar 14, 2013

TDS (Time Domain Sensor) Release*

TDS (Time Domain Sensor) Release*

What is TDS?

TDS, SPEAG’s novel active optical sensor technology for high-speed, high-fidelity, and high-dynamic-range measurements of electric and magnetic fields, exhibits un-paralleled sensitivity over a very large bandwidth. Unlike most other near-field sensor designs, TDS inherently measures the full complex signal information, i.e., the amplitude and phase of the electric or magnetic fields being probed. The exclusive fiber optic link provides full electrical isolation of the miniaturized sensors, which, thus, facilitates true calibration and characterization of our TDS probes, and makes them ideal for use in EM-hostile applications, such as MRI or EMP environments. This novel sensor technology is also the best choice when the impact of loading the field source under test is critical, e.g., in the very close near-field of a component or re-radiating structure. The miniaturization of the active optical sensor technology mastered by SPEAG makes our TDS probes superb for high-resolution near-field measurements, e.g., EMC sniffing and scanning applications.

The superiority of SPEAG’s novel TDS technology over existing sensor designs in many respects makes TDS ideal for a wide range of applications. However, for applications where the emitted signal is narrow-band, well-known, and when the dynamic range required is less than 50dB, e.g., for compliance testing of mobile devices with regard to SAR or HAC limits, our optimized broad-band diode-loaded probes remain the technology of choice.

New - TDS Standalone Systems:

TDS Standalone is the first product of our growing TDS product range to employ SPEAG’s novel active optical sensor technology. A TDS Standalone system consists of a Remote Unit with one or more TDS probes.

Our novel TDS Standalone system. Shown here is a H1TDSz probe, used to sniff the H-fields above a device under test, with a TDS Remote Unit on top of a Spectrum Analyzer, used as the measurement receiver.


TDS Remote Unit:

The TDS Remote Unit is a standalone device that acts as an optical power supply for our TDS probes in the power-over-fiber forward link. In the radio-frequency (RF)-over-fiber reverse link, the TDS Remote Unit converts the optical probe signal to an electrical RF signal equivalent to the electric or magnetic fields sensed at the tip of the TDS probe.

Front view of the TDS Remote Unit, the optical power supply in the power-over-fiber forward link and opto-electrical converter in the RF-over-fiber reverse link.

TDS Probes:

TDS probes are miniaturized active optical magnetic or electrical field probes. For standalone applications, each TDS field probe is fitted with a rugged 8m fiber-optics cable attached directly to the probe. All SPEAG TDS probes are optimized for field measurements in the frequency range 10 MHz – 6 GHz and are individually calibrated and characterized in SPEAG’s calibration laboratory. The following SPEAG single-axis probes for measurement of various vector components of the electric and magnetic fields are scheduled for initial release:

  • H1TDSz:    H-field, parallel to the probe axis.
  • H1TDSx:    H-field, orthogonal to the probe axis.
  • E1TDSz:    E-field, parallel to the probe axis in air.
  • E1TDSx:    E-field, orthogonal to the probe axis in air.

ISO 17025 accredited calibration of TDS probes is expected to be complete by late Summer 2013.

Shown is a H1TDSz magnetic field probe for measurement of the H-field vector component parallel to the probe axis in the frequency range from 10 MHz – 6 GHz.


Further Information on our TDS products:

The Professional Handbook is available for download to all customers:

For more-detailed information about TDS, please visit:

For further information or to receive a quotation, please contact us at:

*available in the US and Canada after final certification in accordance with the regulations of the US FDA, CDRH, CFR 21, Section I, subchapter J, part 1002 to 1040.11 (expected in May 2013).