70GHz oscilloscope sets signal fidelity benchmark

The new oscilloscope incorporates a range of innovations that enable it to more effectively meet the current and future needs of engineers and scientists developing high-speed coherent optical systems or performing leading-edge research.

Dean Miles, Technical Marketing Manager for Tektronix in EMEA carriers seeking more network capacity in transceiver design and the need for an instrument to provide precise low-noise measurements.

“In wideband RF technologies the instrument must provide wider bandwidth and higher resolution,” said Miles.

Tektronix has worked hard to meet these requirements and developed innovations for the new oscilloscopes. The tastiest is Tektronix’s patented Asynchronous Time Interleaving (ATI) technology that preserves signal-to-noise ratio for higher fidelity. It means that users can more accurately capture and measure their signals at higher speeds than previously possible. It enables engineers to see more of their signal details with less noise and distortion so they can make better measurements and understand their system operation better.

To achieve ultra-high bandwidths, other oscilloscope vendors use a frequency interleaving technique that splits the signal into high- and low-frequency bands which are digitized separately. Digitising the bands separately like this introduces noise, and causes phase, amplitude, and other mismatches which are very difficult to overcome when the two bands are reassembled. With Tektronix' patented ATI technology – which uses time interleaving rather than frequency interleaving to achieve high sample rates – the full signal spectrum is digitised by each of two symmetrical signal paths with matched performance, which substantially reduces noise when the full spectrum is recovered.

The oscilloscope also offers 200 GS/s sample rate with 5 ps/sample resolution for improved resolution and timing and a compact form factor that enables the instrument to be positioned very close to the device under test (DUT) while providing flexible display and control for analysis.

Reducing the distance to the DUT enables shorter cable lengths which in turn help to preserve signal fidelity at very high frequencies.

Boasting Tektronix’s patent pending UltraSync architecture the oscilloscope provides precise data synchronisation and convenient operation of multi-unit systems. Precise multi-channel timing synchronisation is key to meeting acquisition requirements in applications such as 100G and faster coherent optical modulation analysis.

UltraSync includes a 12.5 GHz sample clock reference and coordinated trigger bus for inherent acquisition-to-acquisition jitter equivalent to typical channel-to-channel jitter within a single instrument. In addition, it includes a high-speed data path to transfer waveforms from extension units to the master unit for analysis. Since each oscilloscope fully processes its acquired signals, only completed waveforms are sent to the master unit, maintaining performance even as more channels are added. UltraSync allows optical test software to manage a multi-instrument acquisition system for the most precise optical modulation analysis available.

To improve system flexibility, the oscilloscopes are packaged in a 5 ¼in. tall form factor while retaining full high-performance functionality. This compact packaging means that engineers can stack two oscilloscopes in the same space as a standard bench oscilloscope.

The DPO70000SX also provides the flexibility to use one channel at 70 GHz, 200 GS/s or two channels at 33 GHz, 100 GS/s. Available dual unit systems synchronise two DPO70000SX units providing two channels at 70 GHz, 200 GS/s each, or four channels at 33 GHz, 100GS/s operating as a single, coordinated instrument. Dual-unit systems can be easily separated into individual units when needed and a DPO7AFP auxiliary front panel gives direct control of common instrument settings to provide a typical bench oscilloscope experience – for a single unit or a multi-unit system.

The flexibility of the new oscilloscope provides users with the ability to easily scale up to more performance across more channels. For instance, four channels at 33 GHz with insight on two channels at 70 GHz may be sufficient for many of today’s applications. As needs change, two additional units can be added to the configuration to provide four channels at 70 GHz – all functioning as a single instrument.