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 […]
FAQ
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 […]
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’ […]
New products at the EMC & Compliance International Conference
At the annual UK event, Tekbox, Y.I.C. Technologies, and Harogic Technologies were among the companies exhibiting new EMC measurement equipment. The EMC & Compliance International conference and training was held again in Newbury, UK, from May 22 to 23 this year (Reference 1). This was my first opportunity to attend this annual conference hosted by […]
How can I quantify a device’s nonlinearity? part 3
A higher third-order intercept point results in lower intermodulation products at any given input power level below compression. In part 1 of this series, we discussed the 1-dB compression point as a figure of merit for device linearity. In part 2, we examined a circuit that adds two fundamental input signals of frequencies f1 = […]
How to measure PCB trace or power/return plane impedance
PCB impedances can adversely affect signal quality and EMI. Make sure those impedance values are what you expect. Uncontrolled or unexpected impedances on printed circuit board (PCB) traces and power/return planes can negatively impact the performance of electronic devices. Those impedances result from unavoidable but controllable parasitic capacitances and inductances that result from PCB structures […]
How can I quantify a device’s nonlinearity? part 2
A figure of merit called the third-order intercept point indicates how well an RF device minimizes third-order intermodulation products. In part 1, we looked at the 1-dB compression point, which serves as a figure of merit for devices such as RF power amplifiers. An additional specification, the third-order intercept point, abbreviated IP3 or TOI, is […]
NI president: “We are the LabVIEW company”
EE World met with Ritu Favre, who emphasized a return to the company’s product roots. National Instruments, now NI and a part of Emerson, has a long, dominant history in test and measurement. Best known for LabVIEW graphical programming and its supporting cast of software for instrument control and data analysis, NI was founded in […]
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.
