CAUTION

Making Basic Measurements

Measuring Low Level Signals

Measuring Low Level Signals

The ability of the analyzer to measure low level signals is limited by the noise generated inside the analyzer. A signal may be masked by the noise floor so that it is not visible. This sensitivity to low level signals is affected by the measurement setup.

The analyzer input attenuator and bandwidth settings affect the sensitivity by changing the signal-to-noise ratio. The attenuator affects the level of a signal passing through the instrument, whereas the bandwidth affects the level of internal noise without affecting the signal. In the first two examples in this section, the attenuator and bandwidth settings are adjusted to view low level signals.

If, after adjusting the attenuation and resolution bandwidth, a signal is still near the noise, visibility can be improved by using the video bandwidth and video averaging functions, as demonstrated in the third and fourth examples.

Measuring Low Level Signals Example 1:

If a signal is very close to the noise floor, reducing input attenuation brings the signal out of the noise. Reducing the attenuation to 0 dB maximizes signal power in the analyzer.

The total power of all input signals at the analyzer input must not exceed the maximum power level for the analyzer.

1.Connect a signal generator to the analyzer input.

2.Set the signal generator frequency to 300 MHz with an amplitude of

− 80 dBm.

3.On the analyze, perform a factory preset by pressing Preset,

Factory Preset (if present).

4.Set the center frequency of the analyzer to 300 MHz by pressing

FREQUENCY, Center Freq, 300, MHz.

5.Set the span to 5 MHz by pressing SPAN, Span, 5, MHz.

6.Set the resolution bandwidth to spectrum analyzer coupling by pressing BW/Avg, Res BW (SA).

7.Set the Y-Axis Units to dBm by pressing AMPLITUDE, More, Y-Axis Units, dBm.

8.Set the reference level to − 40 dBm by pressing AMPLITUDE, Ref Level,

–40, dBm.

9.Place the signal at center frequency by pressing Peak Search,

Marker→ , Mkr→ CF.

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Chapter 1

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Agilent Technologies E7401A, E7405A, E7402A, E7404A, E7403A manual Measuring Low Level Signals Example
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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.
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