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5 Challenges of Wideband 5G Device Test

Designers and test engineers working on wideband 5G devices require accurate, fast, and cost-effective test solutions to ensure the reliability of new chip designs. Learn about the top test challenges and solutions for wideband 5G IC test

3 min read

1. Waveforms Are Wider and More Complex

5G New Radio includes two different types of waveforms:

  • Cyclic-prefix OFDM (CP-OFDM) for downlink and uplink
  • Discrete Fourier transform spread OFDM (DFT-S-OFDM) for uplink only; this waveform resembles LTE’s single-carrier frequency division multiple access (SC-FDMA)

Researchers and engineers working on 5G device test have the new challenges of creating, distributing, and generating 5G waveforms among their design and test benches. Engineers need to work with highly complex, standard-compliant uplink and downlink signals that have larger bandwidths than ever before. They include a variety of different resource allocations; modulation and coding sets; demodulation, sounding, and phase-tracking information; and single-carrier and contiguous and non-contiguous carrier-aggregated configurations.

Design tip: Select a 5G standard-compliant toolset that allows you to generate, analyze, and share these waveforms between test benches to fully characterize your DUTs.


2. Instruments Must Be Wideband and Linear, and They Must Cost-effectively Cover an Extensive Frequency Range

Although RF engineers have been working with specialized and expensive test systems for mmWave in industries such as aerospace and military, this represents unexplored territory for the mass-market semiconductor industry. Engineers need cost-effective test equipment to configure more test benches for a shorter time to market. These new benches must support high linearity; tight amplitude and phase accuracy over large bandwidths; low phase noise; extensive frequency coverage for multiband devices; and the ability to test for coexistence with other wireless standards. Along with powerful hardware, modular, software-based test and measurement benches will be able to adapt rapidly to new test requirements. 

Design tip: Invest in a wideband test platform that can evaluate performance in both existing and new frequency bands. Select instrumentation that not only supports coexistence with current standards but also adapts to the evolution of the standard over time.


3. Component Characterization and Validation Require More Testing

Working with wide signals below 6 GHz and at mmWave frequencies requires characterizing and validating greater performance out of RF communications components. Engineers must not only test innovative designs for multiband power amplifiers, low-noise amplifiers, duplexers, mixers, and filters, but also ensure that new and improved RF signal chains support simultaneous operation of 4G and 5G technologies. Additionally, to overcome significant propagation losses, mmWave 5G requires beamforming subsystems and antenna arrays, which demand fast and reliable multiport test solutions.

Design tip: Ensure your test systems can handle both multiband and multichannel 5G devices to address beamformers, FEMs, and transceivers.


4. Over-the-air Testing of Massive MIMO and Beamforming Systems Makes Traditional Measurements Spatially Dependent

Engineers working on 5G beamforming devices face the challenge of characterizing the transmit and receive paths and improving the reciprocity for TX and RX. For example, as the transmit power amplifier goes into compression, it introduces amplitude, phase shifts, and other thermal effects that the LNA in the receiver path would not produce. Additionally, the tolerances of phase shifters, variable attenuators, gain control amplifiers, and other devices could cause unequal phase shifts between channels, which affects the anticipated beam patterns. Measuring these effects requires over-the-air (OTA) test procedures that make traditional measurements like TxP, EVM, ACLR, and sensitivity spatially dependent.

Design tip: Use OTA test techniques that synchronize fast and precise motion control and RF measurements to more accurately characterize 5G beamforming systems without exceeding your test time budget.


5. High-volume Production Test Demands Fast and Efficient Scaling

New 5G applications and industry verticals will exponentially increase the number of 5G components and devices that manufacturers need to produce per year. Manufacturers are challenged by the need to provide quick ways to calibrate the multiple RF paths and antenna configurations of new devices and accelerate the OTA solutions for reliable and repeatable manufacturing test results. However, for volume production of RFICs, traditional RF chambers can take up much of the production floor space, disrupt material handling flows, and multiply capital expenses. To tackle these problems, OTA-capable IC sockets—small RF enclosures with an integrated antenna—are now commercially available. These provide semiconductor OTA test functionality in a reduced form factor. 

Design tip: Select an ATE platform that extends lab-grade 5G instrumentation to the production floor to simplify the correlation of characterization and production test data.

Technical White Paper

Engineer’s Guide to 5G Semiconductor Test

Wideband 5G IC test is complex. The Engineer’s Guide to 5G Semiconductor Test is here to help. A must-read for anyone navigating the time, cost, and quality trade-offs of sub-6 GHz and mmWave IC test, the guide features color diagrams, recommended test procedures, and tips for avoiding common mistakes.

Topics include:

  • Working with wide 5G downlink and uplink OFDM waveforms
  • Configuring wideband test benches for extensive frequency coverage
  • Avoiding common sources of error in 5G beamforming
  • Reducing test times of over-the-air TX and RX test procedures
  • Choosing alternatives to RF chambers for high-volume production of mmWave RFICs

 Download the Engineer’s Guide to 5G Semiconductor Test

The Conversation (0)

Why the Internet Needs the InterPlanetary File System

Peer-to-peer file sharing would make the Internet far more efficient

12 min read
An illustration of a series
Carl De Torres

When the COVID-19 pandemic erupted in early 2020, the world made an unprecedented shift to remote work. As a precaution, some Internet providers scaled back service levels temporarily, although that probably wasn’t necessary for countries in Asia, Europe, and North America, which were generally able to cope with the surge in demand caused by people teleworking (and binge-watching Netflix). That’s because most of their networks were overprovisioned, with more capacity than they usually need. But in countries without the same level of investment in network infrastructure, the picture was less rosy: Internet service providers (ISPs) in South Africa and Venezuela, for instance, reported significant strain.

But is overprovisioning the only way to ensure resilience? We don’t think so. To understand the alternative approach we’re championing, though, you first need to recall how the Internet works.

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