About PathWave Vector Signal Analysis (89600 VSA)

PathWave Vector Signal Analysis provides many capabilities for measuring signal quality and troubleshooting problems with RF Radio Frequency: A generic term for radio-based technologies, operating between the Low Frequency range (30k Hz) and the Extra High Frequency range (300 GHz). and baseband signals. These capabilities include vector analysis as well as sophisticated modulation analysis for many types of signals and standards. These measurement capabilities are described below.

There are many ways to view and interact with the results of a measurement through traces and markers. You can also control and query the VSA through several programming interfaces.

Vector measurements

Vector measurements provide extremely fast measurements of magnitude and phase. The VSA also lets you easily change between the frequency and time domains. These capabilities are especially useful in characterizing transient or non-stationary signals.

If you've used a swept-tuned spectrum analyzer before, you already know that narrow resolution bandwidth measurements of small frequency spans are very time-consuming. Traditionally, swept-tuned analyzers have required very long sweep times for narrow resolution bandwidths due to the sweep rate of the narrow filters. The narrower the resolution bandwidth, the more time it takes for the resolution bandwidth filters to settle. In fact, a swept-tuned analyzer's sweep time is inversely proportional to the square of the resolution bandwidth. As you choose increasingly narrower resolution bandwidths (for example, when trying to resolve close-in sidebands) the time it takes to make a measurement increases. This characteristic is common to all conventional swept-tuned analyzers.

However, the 89600 VSA software can make narrowband measurements very quickly. For vector measurements, the analyzer uses the FFT Fast Fourier Transform: A mathematical operation performed on a time-domain signal to yield the individual spectral components that constitute the signal. See Spectrum. (Fast Fourier Transform) to convert the input signal from the time domain to the frequency domain. The result is measurement capability up to 1000 times faster than conventional swept spectrum analyzers.

Vector measurements set the analyzer's local oscillator (LO) to a single frequency during the measurement. Because of this, vector measurements are best for:

Specific examples of applications for Vector measurements include characterizing spurious response of an oscillator or characterizing a bursted signal in both the time and frequency domain.

Some prominent features available with vector measurements are:

See the Standard Features and Measurement Capabilities topic for a more comprehensive list of features available in the 89600 VSA software.

Modulation Analysis

In addition to Vector measurements, the 89600 VSA has many software options that provide the ability to demodulate and analyze many different modulation formats and standards. This includes the flexible modulation analysis options, Digital Demodulation (89601B-AYA/89601AYAC) and Custom OFDM Orthogonal Frequency Division Multiplexing: OFDM employs multiple overlapping radio frequency carriers, each operating at a carefully chosen frequency that is Orthogonal to the others, to produce a transmission scheme that supports higher bit rates due to parallel channel operation. OFDM is an alternative tranmission scheme to DSSS and FHSS. (89601B-BHF/89601BHFC) as well as the other demodulators that are specific to standards such as 5G NR, LTE/LTE-Advanced, and 802.11n/ac/ax.

For information about these optional measurement types, see About Optional Measurement Software for a list of links to the individual measurement types' documentation sections.

See Also

Keysight 89600 VSA Software Installation Guide

Controlling the VSA

Vector Signal Analysis Block Diagram

Time and Frequency Parameter Interactions

Measuring Time Data

Display Resolution: Spectral Displays

Enhancing the Measurement Speed