New-Tech Europe Magazine | August 2016 | Digital edition

from R&D to manufacturing test, but its user-programmable FPGA enabled applications ranging from measurement acceleration to channel emulation. However, the evolution of wireless technology demands a new approach to RF design and test. As a result, NI has introduced a second- generation VST that offers wider bandwidth, extended frequency range, and a larger FPGA in an even smaller form factor. Bandwidth Over the past decade, wireless standards have evolved to use significantly wider bandwidth channels to achieve higher peak data rates. For example, since 2003, Wi-Fi has evolved from 20 to 40 to 160 MHz in today’s 802.11ax. Mobile communication channels have evolved from 200 kHz in GSM to 100 MHz in today’s LTE- Advanced technology. In the future, technologies like LTE-Advanced Pro and 5G will drive this trend even further. Especially when testing semiconductor devices, the bandwidth requirements of the instrument often exceed the bandwidth of the signal. For example, when testing RF power amplifiers (PAs) under digital predistortion (DPD) conditions, the test equipment itself must extract a PA model, correct for nonlinear behavior, and then generate a corrected waveform. Advanced DPD algorithms often require 3X to 5X the RF signal bandwidth. As a result, instrument bandwidth requirements can be up to 500 MHz for LTE- Advanced (100 MHz signal) and 800 MHz for 802.11ac/ax (160 MHz signal). One of the most significant enhancements of the second- generation VST is its wider instantaneous bandwidth: 1 GHz. Because of this wider bandwidth, engineers can use the second- generation VST to solve application challenges that currently can’t be met

Figure 1. Three Use Cases for 5G

Figure 2. DPD Algorithm Using 5x Signal Bandwidth

wireless radios cost 20 percent of today’s prices, next-generation test equipment must be capable of faster and more parallel test approaches. Evolution of the NI Vector Signal Transceiver In 2012, NI announced the revolutionary

new PXI Vector Signal Transceiver (VST). The VST was unique in that it combined a 6 GHz RF signal generator, 6 GHz RF signal analyzer, and a user-programmable FPGA into a single PXI module. Not only did the instrument’s excellent RF performance allow it to serve applications

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