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 […]
wireless
Verify, test, and troubleshoot 5G Wi-Fi FWA gateways
By Xiang Li, Keysight Technologies Follow these three steps to ensure your fixed-wireless access designs will be compatible with the Wi-Fi fronthaul and 5G backhaul. Many areas lack the wired infrastructure to bring residential broadband access. Making those connections has become costly and inefficient. Fixed Wireless Access (FWA) has emerged as a compelling alternative to […]
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 […]
What is intermodulation, and is it good or bad? part 4
Nonlinearities in active circuits and passive components can add harmonic and nonharmonic distortion. This series has investigated intermodulation, the process by which the application of two frequencies to a nonlinear system results in the system generating frequencies that equal the sum and difference of the input frequencies. In Part 1 and Part 2, we looked […]
What is intermodulation, and is it good or bad? part 3
Excel’s charting function adds nonharmonic frequency components to a cosine wave. In Part 1 and Part 2 of this series, we looked at intermodulation — what it is and how to apply it to frequency-translation tasks. We concluded Part 2 with an image like Figure 1. We had begun with a 1,200-kHz carrier with two […]
Spectrum measurements shed light on sign malfunctions
Interference in the 900 MHz band appears to produce random errors in a gas station price sign. Spectrum analyzers help track it down. I received a call recently from a former client who manufactures electronic signs. A gas station was experiencing intermittent loss of wireless control of its signs, which displayed the price of various […]
What is intermodulation, and is it good or bad? Part 2
A mixer can upconvert and downconvert a modulated signal with no loss of baseband information. Part 1 of this series described intermodulation resulting from the combining of two or more sinusoidal signals through a nonlinear device such as the mixer in Figure 1. The mixer’s output is the product of its two inputs, and its […]
What is intermodulation, and is it good or bad? Part 1
Sinusoidal inputs applied to a nonlinear system produce an output containing different frequencies, and the results can be good, bad, or ugly. According to the dictionary definition, intermodulation is “the production in an electrical device of currents having frequencies equal to the sums and differences of frequencies supplied to the device.” In the literature of […]
What is phase noise and how can I measure it? part 2
Phase noise requires more than one instrument unless you use a phase-noise analyzer.
AOC 2023: Exhibits show the latest in military wireless
Washington — The Association of Old Crows (AOC) held its 60th annual convention in Washington during the week of December 11, 2023. EE World was there on December 12. Here is some of what we saw in the exhibit hall. AOC is a defense-oriented conference that focuses on military wireless communications. In addition to product […]
