A constellation diagram plots a quadrature amplitude modulation (QAM) signal’s in-phase and quadrature components. The EE World article “Should I use a spectrum, signal, or vector network analyzer?” in part 3 mentioned that vector-signal analyzers (VSAs) can display modulation-domain and frequency-domain information. Other instruments incorporating digital signal processing (DSP) capabilities, including oscilloscopes, can provide insights into […]
vector network analyzer
Should I use a spectrum analyzer, signal analyzer, or vector network analyzer? Part 4
A vector network analyzer can fully characterize components by deriving their scattering parameters. In earlier parts of this series, we looked at analog spectrum analyzers (part 1 and part 2) and vector signal analyzers (part 3), both of which monitor unknown signals, whether emanating from a system, device under test (DUT), or an enemy’s transmitter […]
Should I use a spectrum, signal, or vector network analyzer? part 3
In part 2 of this series, we looked at a swept-tuned spectrum analyzer and how it could sweep a frequency span of interest from 1 MHz to 1.1 MHz with a sweep time of 50 msec. As Figure 1 shows, the analyzer readily identifies a signal at 1.03 MHz but misses the intermittent signals shown […]
Should I use a spectrum, signal, or vector network analyzer? part 2
An analog spectrum analyzer’s sweep time can hide intermittent unwanted signals. In part 1 of this series, we examined a simplified block diagram of a traditional analog spectrum analyzer, which includes an RF frontend, mixer, voltage-controlled oscillator (VCO), intermediate-frequency (IF) stage, sweep generator, envelope detector, and display. We also looked at resolution bandwidth (RBW), the […]
IMS 2024 roundup: test equipment
Washington, DC — The 2024 International Microwave Symposium took place here in June at the Walter E. Washington Convention Center. As always, RF/microwave/mmWave test equipment was all over the exhibit hall. Frequency-domain test equipment — spectrum analyzers, vector network analyzers, power meters, and signal generators — were, of course, dominant. Other equipment, such as oscilloscopes […]
Should I use a spectrum, signal, or vector network analyzer? part 1
Signal analysis is invaluable for applications ranging from amplifier characterization to signal intelligence. In a recent series, we discussed specs such as 1-dB compression and third-order intercept points. At the end, I pointed to some application notes that explain how to use specific spectrum, signal, and vector network analyzers to make these measurements. These instruments’ […]
How can I quantify a device’s nonlinearity? part 1
You can specify nonlinearity in parts per million or, especially for RF components, in terms of the 1-dB compression point or third-order intercept point.
Wi-Fi 7 approaches, now comes the testing
Keysight’s E7515W lets you test Wi-Fi 7 chipsets and systems.
How to locate EMI emissions with near-field probes: Part 2
Now that you know a little theory of near-field measurements, how do you use near-field probes and a spectrum analyzer to help you troubleshoot and mitigate emissions issues? Remember, as mentioned in Part 1, that deciding whether to use an H-field or E-field probe depends on whether you’ll be probing high switching currents — di/dt […]
IMS 2023 roundup: test equipment
Test equipment plays a major role in product development and production, which was apparent at IMS 2023. In the photos and videos below, you’ll get a taste of test developments at RF, mmWave, and sub-THz frequencies. This year, D-band (110 GHz to 170 GHz) seized a larger portion of the exhibit hall than in past […]
