Making Basic Measurements

Identifying Distortion Products

Figure 1-37 No Harmonic Distortion

Third-Order Intermodulation Distortion

Two-tone, third-order intermodulation distortion is a common test in communication systems. When two signals are present in a non-linear system, they can interact and create third-order intermodulation distortion products that are located close to the original signals. These distortion products are generated by system components such as amplifiers and mixers.

Identifying TOI Distortion Example:

Test a device for third-order intermodulation. This example uses two sources, one set to 300 MHz and the other to approximately 301 MHz. (Other source frequencies may be substituted, but try to maintain a frequency separation of approximately 1 MHz.)

1.Connect the equipment as shown in Figure 1-38. This combination of signal generators, low pass filters, and directional coupler (used as a combiner) results in a two-tone source with very low intermodulation distortion. Although the distortion from this setup may be better than the specified performance of the analyzer, it is useful for determining the TOI performance of the source/analyzer combination. After the performance of the source/analyzer combination has been verified, the device-under-test (DUT) (for example, an amplifier) would be inserted between the directional coupler output and the analyzer input and another measurement would be made.

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Agilent Technologies E7405A, E7402A, E7404A manual Third-Order Intermodulation Distortion, Identifying TOI Distortion Example

E7402A, E7405A, E7404A, E7401A, E7403A specifications

Agilent Technologies, a leader in test and measurement solutions, offers a range of spectrum analyzers designed to meet the evolving demands of the electronics industry. The E7403A, E7401A, E7404A, E7405A, and E7402A are prominent models that embody advanced features and technologies, enhancing performance, accuracy, and user experience.

The E7403A is recognized for its high-quality performance and wide frequency range. This model offers frequency coverage from 9 kHz to 3 GHz, making it suitable for both commercial and academic research applications. With a phase noise of -100 dBc/Hz at 10 kHz offset, it delivers exceptional sensitivity. The E7403A also features a built-in tracking generator, facilitating effective signal generation for testing.

Next in line, the E7401A provides similar frequency coverage but is optimized for portable functionality. Weighing significantly less than its counterparts, it is easy to transport, making it ideal for field applications. Users benefit from its fast sweep speed of up to 3 GHz, which is crucial in quickly identifying and analyzing signals.

The E7404A excels in its comprehensive analysis capabilities. With a frequency range extending up to 6 GHz, it supports more demanding applications, including wireless communications and satellite technology. Its advanced digital signal processing capabilities enable the analysis of complex modulated signals, providing engineers with the data needed to troubleshoot and optimize system performance.

The E7405A is a highly versatile model that offers frequency coverage from 9 kHz to 20 GHz. This wide frequency range, combined with high dynamic range, supports the testing of various electronic devices and systems. It features advanced measurement options including occupied bandwidth, adjacent channel power, and sensitivity measurements, which are critical for compliance testing in communication systems.

Lastly, the E7402A is designed for users who require a spectrum analyzer with enhanced functionality at a competitive price. It reaches frequencies of up to 1.5 GHz, making it suitable for various applications including RF design, development, and manufacturing. Its user-friendly interface ensures that both novice and experienced users can navigate its features with ease.

In conclusion, Agilent Technologies' E7403A, E7401A, E7404A, E7405A, and E7402A spectrum analyzers provide a robust set of features tailored to meet diverse industry needs. Utilizing sophisticated technologies, these models ensure precise and efficient signal analysis, making them indispensable tools for engineers and researchers in the fast-paced world of electronics.