8 Multitone Waveform Generator

In the following sections, this chapter describes the multitone mode, which is available only in E8267D PSG Vector Signal Generators with Option 601 or 602:

•“Overview” on page 185

•“Creating, Viewing, and Optimizing Multitone Waveforms” on page 186 See also: Chapter 3, “Basic Digital Operation,” on page 71

Overview

The multitone mode builds a waveform that has up to 64 CW signals, or tones. Using the Multitone Setup table editor, you can define, modify, and store waveforms for playback. Multitone waveforms are generated by the internal I/Q baseband generator.

The multitone waveform generator is typically used for testing the intermodulation distortion characteristics of multi- channel devices, such as mixers or amplifiers. Intermodulation distortion (IMD) occurs when non- linear devices with multiple input frequencies cause unwanted outputs at other frequencies or interfere with adjacent channels. The multitone waveform generator supplies a waveform with a user- specified number of tones whose IMD products can be measured using a spectrum analyzer and used as a reference when measuring the IMD generated by a

device- under- test.

Multitone waveforms are created using the internal I/Q baseband generator and stored in ARB memory for playback. Although the multitone mode generates a high- quality waveform, a small amount of IMD, carrier feedthrough, and feedthrough- related IMD occurs. Carrier feedthrough may be observed when an even number of tones are generated, since there are no tones at the center carrier frequency to mask the feedthrough. To minimize carrier feedthrough for an even- numbered multitone signal, it is necessary to manually adjust the I and Q offsets while observing the center carrier frequency with a spectrum analyzer.

For measurements that require more than 64 tones or the absence of IMD and carrier feedthrough, you can create up to 1024 distortion- free multitone signals using Agilent Technologies Signal Studio software Option 408.

NOTE For more information about multitone waveform characteristics and the PSG vector signal generator multitone format, download Application Note 1410 from our website by going to http://www.agilent.com and searching for “AN 1410” in Test & Measurement.

Chapter 8

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Agilent Technologies E8257D PSG, E8267D PSG manual Multitone Waveform Generator
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E8267D PSG, E8257D PSG specifications

Agilent Technologies, a recognized leader in electronic measurement and communications solutions, offers a comprehensive range of signal generators, including the E8257D PSG (Pulsed Signal Generator) and E8267D PSG. These instruments are engineered to meet the demanding requirements of wireless communication, aerospace, defense, and various research applications.

The E8257D PSG is known for its versatility and reliability. It operates within a frequency range of 250 kHz to 40 GHz, making it suitable for a wide array of applications, from signal generation to vector modulation. With an output power capability of up to +30 dBm, it delivers high-quality signals with exceptional precision. Its low phase noise performance is especially critical for applications such as radar and communication system testing, where signal integrity is paramount.

One of the standout features of the E8257D is its advanced modulation capabilities, including analog and digital modulation schemes. This flexibility allows engineers to simulate real-world communications environments accurately. The PSG also features a built-in arbitrary waveform generator that enables users to create complex waveforms tailored to specific testing needs, providing a significant advantage in research and development.

On the other hand, the Agilent E8267D PSG is designed to cater to the needs of users requiring a combined signal generation and analysis solution. With the capability to generate signals from 250 kHz to 67 GHz, the E8267D is ideal for millimeter-wave applications, as well as testing next-generation wireless technologies.

This model includes features such as enhanced phase noise performance and faster switching speed, which are crucial for signal integrity in sophisticated networks. The instrument's intuitive user interface and powerful software integration facilitate effortless operation and automation, thereby improving workflow efficiency.

Both the E8257D and E8267D PSG instruments incorporate cutting-edge technologies such as low-noise microwave and RF components, as well as digital signal processing capabilities. They provide users with enhanced accuracy and reliability in their measurements.

In summary, Agilent Technologies' E8257D and E8267D PSG signal generators represent the pinnacle of precision in signal generation technology. With their extensive feature sets, advanced modulation capabilities, and robust performance specifications, these instruments are invaluable tools for engineers and researchers working across various high-tech industries.
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