Block Diagram Theory of Operation

Block Diagram 1

Block Diagram 1

RF Analyzer

Audio Analyzer

Spectrum Analyzer

A23 Input

A24 High Power Attenuator

The A23 Input assembly is both the input for the RF Analyzer section and the final output from the RF Generator section. Additional information on how the A23 Input assembly is used in the signal generator is covered in the Block Diagram 2 discussion.

The RF input signal is input to the HP/Agilent 8922 using either the RF IN/OUT connector (for high power applications > 20 dBm) or using the AUX RF IN connector for lower power input signals. The input signal on the front panel RF IN/OUT connector is first sent to the A24 High Power Attenuator. This attenuates the signal by approximately 14 dB (8 dB on the HP/Agilent 8922F,H,M,S) where it can be directly used by the A23 Input assembly.

The A23 Input assembly has an RF power detector that converts the power on the RF IN/ OUT connector to a dc voltage. This dc signal is sent to the A19 Measurement assembly where it is measured. These dc signals are sent to the A19 Measurement assembly using the det_lo and det_hi inputs to the A19 Measurement assembly. The det_lo signal is lower sensitivity (for the highest power signals) and det_hi is high sensitivity (for lower power signals). Accurate RF power measurement can only be made using the RF IN/OUT connector on the HP/Agilent 8922. These circuits are used to measure both CW and Pulsed RF power. For accurate RF power measurements it is necessary to zero the power meter and enter the frequency of the RF input signal. These two functions will cause the power meter to use the proper correction factors to compensate for temperature changes and frequency losses.

After the power detector, the RF IN/OUT connector is routed to a power splitter and then an RF switch. This switch selects between the RF IN/OUT signal or the AUX RF IN signal.

Selectable input attenuators in the A23 Input assembly are switched in and out, manually or automatically. This keeps the input level within a range that works best for the mixers, IF amplifiers, and detector in the remainder of the HP/Agilent 8922. Filters are automatically switched in to remove images and other interfering signals. The frequency ranges of the 4 different filters are shown on Block Diagram 1.

The A23 Input assembly contains a voltage multiplexer (mux) to route internal diagnostic voltages to the A19 Measurement assembly. Diagnostics individually check that all the input attenuator switches provide attenuation, although the accuracy of this measurement

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Agilent Technologies 8922 manual Block Diagram, A23 Input A24 High Power Attenuator
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8922 specifications

Agilent Technologies 8922 is a versatile and robust mobile communication test set, designed to fulfill the demanding requirements of wireless device manufacturers and service providers. Primarily focused on mobile radio communications, the 8922 provides a comprehensive solution for testing a wide array of signaling standards and technologies, making it essential in the rapidly evolving telecommunications landscape.

One of the standout features of the Agilent 8922 is its support for multiple wireless standards, including GSM, GPRS, EDGE, WCDMA, and HSPA. This makes the device an ideal choice for testing mobile devices that operate on different generations of cellular networks. Additionally, the 8922 is equipped with advanced measurement capabilities, allowing users to perform key performance indicators assessments, such as power, modulation quality, and spectral emission analysis, ensuring devices meet stringent regulatory and performance standards.

The 8922 is designed with an intuitive user interface that simplifies the setup and execution of tests. It features a large color display, making it easier for users to view test results and navigate through various functions. The built-in automation capabilities enable seamless integration into production environments, where efficiency and repeatability are crucial for high-volume testing.

Technologically, the Agilent 8922 incorporates advanced signal processing algorithms, which enhance its measurement accuracy and speed. The device's architecture allows for real-time analysis of signals, enabling users to identify issues quickly and efficiently. This is particularly important in the realm of mobile communications, where time-to-market is critical for competitive advantage.

Another significant characteristic of the 8922 is its flexible configuration options. Users can customize the test set with different hardware and software modules to suit specific testing needs. This scalability ensures that the 8922 remains relevant as wireless technologies evolve and new standards emerge.

In conclusion, the Agilent Technologies 8922 is an indispensable tool for professionals engaged in the testing of mobile communications devices. Its broad support for multiple standards, advanced measurement capabilities, user-friendly design, and flexibility make it a top choice in the telecommunications testing community. As the mobile communication industry continues to advance, the 8922 stands out as a leading solution for ensuring that devices meet quality and performance expectations.
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