Strong demands being placed on T&M equipment

Electronic components can be equipped with multiple communications interfaces for different application scenarios. It starts with the usual serial bus interfaces, such as I²C, SPI, USB, PCI Express and MIPI. Then there are industry-specific bus interfaces and network cards. The high speed versions are heading toward transmission rates of several gigabits per second, depending on the technology. Most electronic components also have integrated wireless interfaces, which in future will be designed for 5G, Gigabit WiFi or NB IoT. For near field communications, manufacturers often integrate a Bluetooth interface or, in the smart home/office area, an interface for Zigbee data transmission.

Coexistence tests are increasing in importance

When electronic components are put into operation, all of these tightly integrated interfaces must be able to transmit and receive their signals without interference, even when they are active at the same time. This can only be tested during development or during pre-compliance testing in a realistic test environment. The test equipment must be designed for the transmission technologies concerned.

For wireless transmissions, the wireless testers of the Rohde & Schwarz R&S CMW platform can simultaneously test cellular and non-cellular transmissions – even Bluetooth LE. Rohde & Schwarz has developed the first RF signalling test solution for testing over the air interface under realistic conditions. This is the only way to perform realistic coexistence tests.

With conducted transmissions, an instrument such as an oscilloscope would have to be able to recognise all of the transmission technologies concerned and decode them in real time. It is convenient if the user can see at a glance which event in the signal led to a faulty bus protocol transfer. Especially when making cable or PCB measurements, the test setup can noticeably influence the measurement.

This influence can be removed using computational deembedding. In cooperation with leading semiconductor and cable manufacturers, Rohde & Schwarz has developed a suitable algorithm for vector signal analyzers. The new high-performance oscilloscopes in the R&S RTP family even provide real-time deembedding, allowing the trigger system to directly access the deembedded signal. All trigger types are supported up to the maximum bandwidth of 16GHz. For troubleshooting on signal lines, there is also an option for transmission and reflection measurements in the time domain.

Reliably measuring extremely low voltages

Embedded designs integrate countless modules and components, which now often work with very low, tight tolerance supply voltages to achieve the longest possible battery life for the device. Progressive miniaturisation will exacerbate this. Developers need to be able to measure current consumption down to the nanoamp range in all operating modes and estimate the impact of power-saving modes in order to optimise devices with ultra-low power consumption.

Another issue is that fast digital signals and other disturbance sources can be coupled into the DC supply voltage network. Oscilloscopes with especially low noise and bandwidths in the GHz range are therefore required. Another decisive factor is high vertical input sensitivity in combination with a broadband 1:1 power rail probe. An oscilloscope with a high update rate is required in order to reliably capture rare events. The oscilloscopes in the R&S RTP family acquire up to 750,000 waveforms per second, allowing developers to quickly and accurately characterise power supplies.

These examples illustrate the rising requirements on the sensitivity and bandwidth of test and measurement equipment. And coexistence is becoming more and more important. This means that ideally, test equipment must be flexible and configurable via software options.